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#81
Posted to sci.electronics.design,rec.audio.tech
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another bizarre audio circuit
On Mar 2, 5:58*pm, John Larkin
wrote: On Wed, 2 Mar 2011 14:55:18 -0800 (PST), Fred Bloggs wrote: On Mar 2, 4:33 pm, John Larkin wrote: On Wed, 2 Mar 2011 12:03:38 -0800 (PST), Fred Bloggs wrote: On Mar 2, 11:40 am, John Larkin wrote: I've always sort of liked the classic "GE" tape head/mic preamp circuit: ftp://jjlarkin.lmi.net/GEcircuit.jpg but it occurred to me that it might also make a nice headphone amp.... ftp://jjlarkin.lmi.net/GE_headphone_amp.JPG Audio tends to be nonsense, but at least the audio guys have fun playing with circuits, whether they make a lot of sense or not. John Bizarre??? Just a standard buffered input CE with negative feedback DC bias to stabilize the operating point against Vbe and reverse leakage collector current change with temperature- a textbook circuit... Which textbook? John- Hide quoted text - - Show quoted text - Just about any textbook that goes into bias point sensitivity analysis of transistor circuits- you remember the S- functions, mainly ICQ stability. The big three were HFE, VBE, and ICBO. Then the rest of your circuit is just ac-bypass and the shunt-series feedback for signals. I've seen it dozens of times. I bet you haven't seen the bipolar+mosfet version, with inductive pullup, used as a power amp. John- Hide quoted text - - Show quoted text - I don't see the MOSFET being all that much of a change. And as for the inductor pull-up, this just doesn't make sense for low wattage high impedance headphone loads. Your inductive reactance needs to be a good few integer multiples of the load impedance, making these things prohibitively large if not unobtainable for a headphone app- you would use far less iron/ ferrite by boost switching your supply to accommodate the output swing...guess that's why I've never seen the inductive pullup here. |
#82
Posted to sci.electronics.design,rec.audio.tech
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another bizarre audio circuit
On 3/3/2011 12:04 AM, John Larkin wrote:
On Wed, 02 Mar 2011 22:45:48 -0600, John - wrote: On 3/2/2011 10:24 PM, John Larkin wrote: On Wed, 02 Mar 2011 22:06:41 -0600, John - wrote: On 3/2/2011 8:52 PM, John Larkin wrote: On Wed, 02 Mar 2011 20:40:27 -0600, John - wrote: On 3/2/2011 8:32 PM, John Larkin wrote: On Wed, 2 Mar 2011 17:59:58 -0800 (PST), Bill Sloman wrote: On Mar 3, 2:11 am, John Larkin wrote: On Wed, 02 Mar 2011 18:36:25 -0600, John Fields wrote: On Wed, 02 Mar 2011 08:40:42 -0800, John Larkin wrote: I've always sort of liked the classic "GE" tape head/mic preamp circuit: ftp://jjlarkin.lmi.net/GEcircuit.jpg but it occurred to me that it might also make a nice headphone amp... ftp://jjlarkin.lmi.net/GE_headphone_amp.JPG Audio tends to be nonsense, but at least the audio guys have fun playing with circuits, whether they make a lot of sense or not. John --- Even though you scorn and ridicule audio, there's nothing wrong with anyone seeking perfection there, just as there's nothing wrong with your search for perfection in the genre which pleases _you_ to pursue. So, speaking of fun, why don't you do a complete design and assign values to the circuit components and identify the semiconductors? You're not playing the game. You are sitting in the henhouse, clucking about the people who do. He's not playing your game, which involves telling John Larkin how cute his circuits are. He's not designing circuits, which is what this newsgroup is about. You aren't either. Both of you start to cluck and peck when people do design circuits. No surprise. Or is that legwork _we're_ supposed to do in order to flesh out your divine revelation? Chickenleg work! It's half the story - a few component values make it a lot easier to work out what a circuit is doing. You can't look at a circuit this simple and see what it's doing? OK, no surprise. John Well, I thought designing a circuit included supplying component values. No? I posted topologies. Values can be scaled to the application, but you need a topology first. If I were actually going to build this, for money, of course I'd have to define specs and then compute values. That's just grunt work. John Not really. I have a few circuits I could throw out and claim that they are topologies and you would not be able to use them without values. Granted, mine are more complex than the one being discussed, but I'm hoping to make a point. John (not Larkin) I think circuit topologies are fun to play with. Lots of textbooks show, and discuss, circuits without explicit values. Once you have a topology, then you can proceed to specs and component values. If you think all circuits should be posted with values, post some. John You are correct, John. Now you have a topology. Please post the component values. Thanks, John Given i/o specs, the DC analysis is simple. But there are two AC aspects that are sort of interesting: the lf response, and loop stability. I'm sort of disappointed that nobody has commented on either. As I'm disappointed in how many people want to whine and cluck about personalities, and avoid actually discussing electronics. John Okay, I put some values to it. It looks like a nice circuit, I admit. Good gain, low distortion, reasonable input impedance. Mind you, I didn't try to optimize it. I did notice that the feedback took higher than expected resistance and I was a bit surprised that the emitter capacitor of the output stage made the response do a camel hump at the beginning if too high. So, critique away. I might learn something. Version 4 SHEET 1 880 680 WIRE 32 -496 -240 -496 WIRE 352 -496 32 -496 WIRE -240 -400 -240 -496 WIRE 32 -400 32 -496 WIRE 352 -400 352 -496 WIRE -240 -304 -240 -320 WIRE 352 -288 352 -320 WIRE 352 -288 160 -288 WIRE 528 -288 352 -288 WIRE 560 -288 528 -288 WIRE 352 -224 352 -288 WIRE 32 -176 32 -320 WIRE 288 -176 32 -176 WIRE 160 -96 160 -288 WIRE 160 32 160 -16 WIRE 32 80 32 -176 WIRE -320 128 -336 128 WIRE -272 128 -320 128 WIRE -112 128 -208 128 WIRE -32 128 -112 128 WIRE -336 208 -336 128 WIRE 32 208 32 176 WIRE 160 208 160 96 WIRE 160 208 32 208 WIRE -112 288 -112 128 WIRE 128 288 -112 288 WIRE 352 288 352 -128 WIRE 352 288 208 288 WIRE 448 288 352 288 WIRE -336 320 -336 288 WIRE 32 384 32 208 WIRE 352 384 352 288 WIRE 448 384 448 288 WIRE 32 480 32 464 WIRE 352 480 352 464 WIRE 448 480 448 448 FLAG -240 -304 0 FLAG 32 480 0 FLAG 352 480 0 FLAG 448 480 0 FLAG -336 320 0 FLAG -320 128 in FLAG 528 -288 out SYMBOL npn -32 80 R0 SYMATTR InstName Q1 SYMATTR Value 2N3904 SYMBOL npn 288 -224 R0 SYMATTR InstName Q2 SYMATTR Value 2N3904 SYMBOL cap -272 144 R270 WINDOW 0 32 32 VTop 0 WINDOW 3 0 32 VBottom 0 SYMATTR InstName C1 SYMATTR Value 10µ SYMBOL res 112 304 R270 WINDOW 0 32 56 VTop 0 WINDOW 3 0 56 VBottom 0 SYMATTR InstName R1 SYMATTR Value 47k SYMBOL res 16 368 R0 SYMATTR InstName R2 SYMATTR Value 1k SYMBOL res 336 368 R0 SYMATTR InstName R3 SYMATTR Value 1.8k SYMBOL cap 432 384 R0 SYMATTR InstName C2 SYMATTR Value 47µ SYMBOL res 336 -416 R0 SYMATTR InstName R4 SYMATTR Value 3.3k SYMBOL res 16 -416 R0 SYMATTR InstName R5 SYMATTR Value 4.7k SYMBOL voltage -240 -416 R0 WINDOW 123 0 0 Left 0 WINDOW 39 0 0 Left 0 SYMATTR InstName V1 SYMATTR Value 9 SYMBOL res 144 -112 R0 SYMATTR InstName R6 SYMATTR Value 150k SYMBOL cap 144 32 R0 SYMATTR InstName C3 SYMATTR Value .1µ SYMBOL voltage -336 192 R0 WINDOW 123 24 132 Left 0 WINDOW 39 0 0 Left 0 SYMATTR InstName V2 SYMATTR Value SINE(0 5m 1000) SYMATTR Value2 AC 1m TEXT -370 504 Left 0 !.tran 0 510m 500m TEXT -1072 8 Left 0 !;ac dec 100000 10 100k |
#83
Posted to sci.electronics.design,rec.audio.tech
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another bizarre audio circuit
On Thu, 03 Mar 2011 18:04:33 -0800, Chieftain of the Carpet Crawlers
wrote: On Thu, 03 Mar 2011 08:59:38 -0800, John Larkin wrote: Stop whining and clucking about personalities Stop with the retarded colloquialisms (or attempts at them). You stupid ****. That is about as plain as it gets. You show with nearly every post just how little a man you are. If you even get that qualification. Your personality is that of a circus flea. Dance, mother****er. The thing you guys have in common is that you suck at electronics, and you know it. That pretty much explains everything. John |
#84
Posted to sci.electronics.design,rec.audio.tech
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another bizarre audio circuit
On Thu, 03 Mar 2011 22:17:46 -0600, John - KD5YI
wrote: On 3/3/2011 12:04 AM, John Larkin wrote: On Wed, 02 Mar 2011 22:45:48 -0600, John - wrote: On 3/2/2011 10:24 PM, John Larkin wrote: On Wed, 02 Mar 2011 22:06:41 -0600, John - wrote: On 3/2/2011 8:52 PM, John Larkin wrote: On Wed, 02 Mar 2011 20:40:27 -0600, John - wrote: On 3/2/2011 8:32 PM, John Larkin wrote: On Wed, 2 Mar 2011 17:59:58 -0800 (PST), Bill Sloman wrote: On Mar 3, 2:11 am, John Larkin wrote: On Wed, 02 Mar 2011 18:36:25 -0600, John Fields wrote: On Wed, 02 Mar 2011 08:40:42 -0800, John Larkin wrote: I've always sort of liked the classic "GE" tape head/mic preamp circuit: ftp://jjlarkin.lmi.net/GEcircuit.jpg but it occurred to me that it might also make a nice headphone amp... ftp://jjlarkin.lmi.net/GE_headphone_amp.JPG Audio tends to be nonsense, but at least the audio guys have fun playing with circuits, whether they make a lot of sense or not. John --- Even though you scorn and ridicule audio, there's nothing wrong with anyone seeking perfection there, just as there's nothing wrong with your search for perfection in the genre which pleases _you_ to pursue. So, speaking of fun, why don't you do a complete design and assign values to the circuit components and identify the semiconductors? You're not playing the game. You are sitting in the henhouse, clucking about the people who do. He's not playing your game, which involves telling John Larkin how cute his circuits are. He's not designing circuits, which is what this newsgroup is about. You aren't either. Both of you start to cluck and peck when people do design circuits. No surprise. Or is that legwork _we're_ supposed to do in order to flesh out your divine revelation? Chickenleg work! It's half the story - a few component values make it a lot easier to work out what a circuit is doing. You can't look at a circuit this simple and see what it's doing? OK, no surprise. John Well, I thought designing a circuit included supplying component values. No? I posted topologies. Values can be scaled to the application, but you need a topology first. If I were actually going to build this, for money, of course I'd have to define specs and then compute values. That's just grunt work. John Not really. I have a few circuits I could throw out and claim that they are topologies and you would not be able to use them without values. Granted, mine are more complex than the one being discussed, but I'm hoping to make a point. John (not Larkin) I think circuit topologies are fun to play with. Lots of textbooks show, and discuss, circuits without explicit values. Once you have a topology, then you can proceed to specs and component values. If you think all circuits should be posted with values, post some. John You are correct, John. Now you have a topology. Please post the component values. Thanks, John Given i/o specs, the DC analysis is simple. But there are two AC aspects that are sort of interesting: the lf response, and loop stability. I'm sort of disappointed that nobody has commented on either. As I'm disappointed in how many people want to whine and cluck about personalities, and avoid actually discussing electronics. John Okay, I put some values to it. It looks like a nice circuit, I admit. Good gain, low distortion, reasonable input impedance. Mind you, I didn't try to optimize it. I did notice that the feedback took higher than expected resistance and I was a bit surprised that the emitter capacitor of the output stage made the response do a camel hump at the beginning if too high. Yeah, C3 gives the overall amp response a low frequency bump, and C1 and C2 each contribute a low frequency rolloff. They all have to be balanced to make it flat. Probably eliminating C3 is a good idea, if the DC biasing still works. When I used this as a tape head preamp, the LF boost was an asset, part of the tape head response equalization. R2 could be a lot lower. The open-loop voltage gain of Q1 is just R5/R2, which is only 5, which is pretty low... even lower when it's loaded by Q2. Or, another way to look at it, R2 kills the transconductance of Q1, and adds noise. If you do my power amp version, with a mosfet for Q2 and an inductor for R4, there's another LF rolloff and the loop stability situation is horrifying. John |
#85
Posted to sci.electronics.design,rec.audio.tech
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another bizarre audio circuit
On Thu, 3 Mar 2011 19:08:38 -0800 (PST), George Herold
wrote: On Mar 3, 6:49*pm, John Larkin wrote: On Thu, 3 Mar 2011 15:21:33 -0800 (PST), Bill Sloman wrote: On Mar 3, 4:12 pm, John Larkin wrote: On Thu, 3 Mar 2011 00:10:16 -0800 (PST), Bill Sloman wrote: On Mar 3, 3:32 am, John Larkin wrote: On Wed, 2 Mar 2011 17:59:58 -0800 (PST), Bill Sloman wrote: On Mar 3, 2:11 am, John Larkin wrote: On Wed, 02 Mar 2011 18:36:25 -0600, John Fields wrote: On Wed, 02 Mar 2011 08:40:42 -0800, John Larkin wrote: I've always sort of liked the classic "GE" tape head/mic preamp circuit: ftp://jjlarkin.lmi.net/GEcircuit.jpg but it occurred to me that it might also make a nice headphone amp... ftp://jjlarkin.lmi.net/GE_headphone_amp.JPG Audio tends to be nonsense, but at least the audio guys have fun playing with circuits, whether they make a lot of sense or not. John --- Even though you scorn and ridicule audio, there's nothing wrong with anyone seeking perfection there, just as there's nothing wrong with your search for perfection in the genre which pleases _you_ to pursue. So, speaking of fun, why don't you do a complete design and assign values to the circuit components and identify the semiconductors? You're not playing the game. You are sitting in the henhouse, clucking about the people who do. He's not playing your game, which involves telling John Larkin how cute his circuits are. He's not designing circuits, which is what this newsgroup is about. You aren't either. Both of you start to cluck and peck when people do design circuits. No surprise. Or is that legwork _we're_ supposed to do in order to flesh out your divine revelation? Chickenleg work! It's half the story - a few component values make it a lot easier to work out what a circuit is doing. You can't look at a circuit this simple and see what it's doing? OK, no surprise. Without the component values, it does take a moment's thought, which is wasted on a bizarre (if simple) circuit with few potential applications. Millions of the "GE" circuit have been used for decades. The mosfet hybrid is a very reasonable headphone amp. Post a circuit, doofus. You've forgotten how to do anything but whine. You are the one who complains all the time. You may have personal preferences about the nature of the threads that get started here, and the responses that get posted, but they are only of interest to you. You are welcome to demonstrate your preferences by choosing to get involved with particular threads and in your particular reactions to other responses, but your whining about the nature of those responses doesn't make the group a more attractive or rewarding environment. In the meantime, I'll post a circuit when I've got a circuit worth posting. Posting a example - without comnponent values - of a circuit that has been used in millions, for decades, doesn't strike me as a profitable use of bandwidth, but that is a personal preference. What I did was spin a signal-level bipolar circuit into a bipolar-mosfet power amp of similar topology. The resulting dynamics is very interesting. Well, not to you. John- Hide quoted text - - Show quoted text - Yeah, I didn't get the inductor part. Do I have to spice it? Or does it have to do with head phone dynamics. Say, and what about using the postive rail of an opamp as an output? I never heard of that. George H. Old trick. Here's a bipolar-swing version. ftp://jjlarkin.lmi.net/Opamp_boost_2.JPG A similar thing is sometimes done to boost the current of an LM317, by using its input current to drive the base of a PNP "helper" transistor. I use a variant of this circuit as a current splitter in my NMR gradient amps. I can't spell, or type, either. John |
#86
Posted to sci.electronics.design,rec.audio.tech
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another bizarre audio circuit
On Thu, 03 Mar 2011 16:04:06 -0800, John Larkin
wrote: On Thu, 3 Mar 2011 14:42:40 -0800 (PST), " wrote: On 2 Mar., 17:40, John Larkin wrote: I've always sort of liked the classic "GE" tape head/mic preamp circuit: ftp://jjlarkin.lmi.net/GEcircuit.jpg but it occurred to me that it might also make a nice headphone amp... ftp://jjlarkin.lmi.net/GE_headphone_amp.JPG Audio tends to be nonsense, but at least the audio guys have fun playing with circuits, whether they make a lot of sense or not. John speaking of bizarre : http://tubetime.us/?p=85 I'm sure someone here will love it -Lasse Wild. Sort of a single-slope ADC and a PWM driver. I wonder what the sensitivity is like. I bet you do a similar thing with a single tiny-logic schmitt gate. Vaguely a superregenerative idea, namely triggering along a slowly decaying exponential. John Yeah, this might work: ftp://jjlarkin.lmi.net/Schmitt_Radio.JPG John |
#87
Posted to sci.electronics.design,rec.audio.tech
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another bizarre audio circuit
On Wed, 02 Mar 2011 08:40:42 -0800, John Larkin wrote:
I've always sort of liked the classic "GE" tape head/mic preamp circuit: ftp://jjlarkin.lmi.net/GEcircuit.jpg but it occurred to me that it might also make a nice headphone amp... ftp://jjlarkin.lmi.net/GE_headphone_amp.JPG I plugged this into LTspice and with a bit of twiddling appears to work well, at least under simulation. I used a supply V of 15V, transistor input resistor (R1) = 100K, input capacitor (C1) = 1uF, transistor emitter resistor (R2) = 3.3K, feedback resistor (R3) = 22K, cap in series with feedback resistor (C3) = 10uF, bypass capacitor (C2) = 2200uF (needs to be big or lose LF gain/damping) output capacitor (C4) = 470uF (let it charge before connecting) inductor size of 10 henries (for sim assuming perfect, 0 ohms) transistor collector resistor (R4) = 3.6K but can vary, mosfet source resistor (R5, parallel with C2) = 47 but can vary. Transistor = whatever (2N5550 in sim), mosfet = IRL530. These values optimize for medium output power (570mW) into 50 ohms and reasonable power (around 300mW) into 32 ohms and 100 ohms but with off-center clipping. R4 and R5 can be varied to deliver the desired power into the desired load... some of the values I tried... 100 ohm load.. R4=22K R5=22 PDQ=1.5W PDR5=0.3W Pout=730mW into 100, 370mW into 50, 220mW into 32 50 ohm load... R4=9.1K R5=22 PDQ=2.2W PDR5=0.9W Pout=1000mW into 50, 660mW into 32, 530mW into 100 50 ohm load... R4=5.6K R5=33 PDQ=1.6W PDR5=1.1W Pout=788mW into 50, 490mW into 32, 400mW into 100 50 ohm load... R4=3.6K R5=47 PDQ=1.2W PDR5=1.1W Pout=570mW into 50, 330mW into 32, 290mW into 100 32 ohm load... R4=5.1K R5=22 PDQ=2.5W PDR5=1.7W Pout=1180mW into 32, 760mW into 50, 380mW into 100 32 ohm load... R4=3.3K R5=33 PDQ=1.7W PDR5=1.7W Pout=790mW into 32, 560mW into 50, 280mW into 100 32 ohm load... R4=2.2K R5=47 PDQ=1.2W PDR5=1.6W Pout=500mW into 32, 400mW into 50, 200mW into 100 (PDQ is mosfet dissipation, PDR5 is R5 dissipation) R5 sets the overall power level, then adjust R4 to achieve balanced clipping. Output impedance is fairly low, not much variance as load changes. Gain is approximately R3/R2 plus a bit. Distortion increases as R4 (and open loop gain) decreases but it appears rather "tuby". A 10 henry inductor is probably overkill, anything 1H or more will probably be fine, for a HP amp there's plently of overhead and the negative feedback will mostly correct for deficiencies, smaller inductors just have less output at 20hz. Could probably use the secondary of an output transformer with the primary insulated.. but watch out for core saturation. Should have fairly low resistance, preferably less than a few ohms (can tweak values to compensate). Someone in the thread said large inductors are "unobtainium" but that's BS, transformer windings ARE huge inductors, for this level of power a winding of a power transformer will probably work. For class A amps using an inductor or transformer output doubles efficiency and halves the supply voltage needed for a given output. It also presents a high impedance at audio frequencies so that only the load determines the impedance (thus the gain) of the output stage. It's possible to use a resistor load but won't perform as well. Audio tends to be nonsense, but at least the audio guys have fun playing with circuits, whether they make a lot of sense or not. John But this one does make sense. There's a reason this basic circuit has been around about as long as transistors... Terry |
#88
Posted to sci.electronics.design,rec.audio.tech
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another bizarre audio circuit
On Mar 4, 4:43*am, Chieftain of the Carpet Crawlers
wrote: On Thu, 3 Mar 2011 18:37:42 -0800 (PST), Bill Sloman wrote: On Mar 4, 3:31 am, Chieftain of the Carpet Crawlers wrote: On Thu, 3 Mar 2011 14:42:40 -0800 (PST), " wrote: On 2 Mar., 17:40, John Larkin wrote: I've always sort of liked the classic "GE" tape head/mic preamp circuit: ftp://jjlarkin.lmi.net/GEcircuit.jpg but it occurred to me that it might also make a nice headphone amp.... ftp://jjlarkin.lmi.net/GE_headphone_amp.JPG Audio tends to be nonsense, but at least the audio guys have fun playing with circuits, whether they make a lot of sense or not. John speaking of bizarre :http://tubetime.us/?p=85 I'm sure someone here will love it -Lasse Pretty good stuff. It will go way over Sloman's head. Along with the hundred other things a boy can do with a 555. So someone has used a 555 to make a less than impressive radio- receiver. Why would anybody be interested, if they hadn't fixated on the device early in their career and never moved on? * Oh, sorry, oh guru. * You are right, that is what 90% of the rest of the world has done. *Not moved on. * Or could it be that it is *you* that has the problem? Not really. Most of the people who post here haven't used a 555 for years. Not because they don't know about it or don't like it but because the kind of problem that it was designed to solve started being solved in other wau=ys around 1980. * You are the one that is not impressive. I don't impress me. I see no reason why I should impress you. -- Bill Sloman, Nijmegen |
#89
Posted to sci.electronics.design,rec.audio.tech
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another bizarre audio circuit
Bill Sloman writes:
On Mar 4, 4:43Â*am, Chieftain of the Carpet Crawlers wrote: [...] Â* You are the one that is not impressive. I don't impress me. I see no reason why I should impress you. Tempting to put that on my sig. -- John Devereux |
#90
Posted to sci.electronics.design,rec.audio.tech
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another bizarre audio circuit
On Wed, 02 Mar 2011 08:40:42 -0800, John Larkin wrote:
I've always sort of liked the classic "GE" tape head/mic preamp circuit: ftp://jjlarkin.lmi.net/GEcircuit.jpg but it occurred to me that it might also make a nice headphone amp... ftp://jjlarkin.lmi.net/GE_headphone_amp.JPG Audio tends to be nonsense, but at least the audio guys have fun playing with circuits, whether they make a lot of sense or not. John Ironically, it looks somewhat similar to the old style fuzz face guitar effect. http://geofex.com/Article_Folders/fuzzface/fftech.htm |
#91
Posted to sci.electronics.design,rec.audio.tech
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another bizarre audio circuit
On Fri, 4 Mar 2011 02:35:52 -0800 (PST), Bill Sloman
wrote: Not really. Most of the people who post here haven't used a 555 for years. You do not know that, and you saying it does not make it true. You are an idiot to think so. |
#92
Posted to sci.electronics.design,rec.audio.tech
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another bizarre audio circuit
On Fri, 04 Mar 2011 10:55:15 +0000, John Devereux
wrote: Bill Sloman writes: On Mar 4, 4:43*am, Chieftain of the Carpet Crawlers wrote: [...] * You are the one that is not impressive. I don't impress me. I see no reason why I should impress you. Tempting to put that on my sig. Only if it is a collection of stupid remarks. |
#93
Posted to sci.electronics.design,rec.audio.tech
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another bizarre audio circuit
On Thu, 03 Mar 2011 15:55:19 -0800, John Larkin
wrote: On Thu, 03 Mar 2011 14:44:58 -0600, John Fields wrote: On Thu, 03 Mar 2011 10:22:31 -0800, John Larkin wrote: On Thu, 03 Mar 2011 12:07:36 -0600, John Fields wrote: --- The truth _is_ you have less of an interest in discussing electronics in a give-and-take kind of way than you do in exalting yourself, so I prefer to generally opt out of any threads you infect. --- JF I didn't "infect" this thread, I started it. --- Then it was diseased from the beginning. --- So why have you posted so much cluckey blather here? --- You call it "cluckey blather" in an attempt to belittle it, I call it what it is: criticism. Criticism would have some content. --- It does, and the content accurately enumerates your foibles, which is anathema to you since you've managed to convince yourself and are trying to convince everyone else that you're perfect in every way. --- You know, something having to do with the circuit. --- There are no rules here, as you've proved by your gross abuse of the newsgroup with your legion off-topic posts, and if I choose to not comment on your circuit, that's my right. --- All you've done is whine. --- Not so. What I've done is simply point out technical errors which you've made, over the years, and then been forced to respond to the calumny you invariably invoke in order to try to make your stance seem unsullied. --- You refuse to discuss this circuit, then you attack me personally for not doing give-and-take discussion of this circuit! --- It's not an attack, it's an observation, and it's not about this circuit in particular, it's about your fanatical need to be in control. Electronic design is all about control. Of signals. But you probably meant some sort of personal control. How does posting a circuit, and opening it for discussion, suggest control? I thought discussing circuits is what s.e.d. is for. --- Then why do you defy the group's charter by posting off-topic, irrelevant nonsense? --- You're just a crabby old git who won't discuss electronics. --- With you, since all you're interested in is fostering your agenda, the inflation of your ego. However, with others I have little reticence to join in a discussion, and often do. For instance, I'll refer you to the "Driving Triac Directly with 555 Output?", the "Looking for cheap, simple PIR detector module" and the "24-bit on tap at Apple?" threads. --- JF |
#94
Posted to sci.electronics.design,rec.audio.tech
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another bizarre audio circuit
On Fri, 04 Mar 2011 06:31:40 -0600, John Fields
wrote: On Thu, 03 Mar 2011 15:55:19 -0800, John Larkin wrote: On Thu, 03 Mar 2011 14:44:58 -0600, John Fields wrote: On Thu, 03 Mar 2011 10:22:31 -0800, John Larkin wrote: On Thu, 03 Mar 2011 12:07:36 -0600, John Fields wrote: --- The truth _is_ you have less of an interest in discussing electronics in a give-and-take kind of way than you do in exalting yourself, so I prefer to generally opt out of any threads you infect. --- JF I didn't "infect" this thread, I started it. --- Then it was diseased from the beginning. --- So why have you posted so much cluckey blather here? --- You call it "cluckey blather" in an attempt to belittle it, I call it what it is: criticism. Criticism would have some content. --- It does, and the content accurately enumerates your foibles, which is anathema to you since you've managed to convince yourself and are trying to convince everyone else that you're perfect in every way. --- You know, something having to do with the circuit. --- There are no rules here, as you've proved by your gross abuse of the newsgroup with your legion off-topic posts, and if I choose to not comment on your circuit, that's my right. --- All you've done is whine. --- Not so. What I've done is simply point out technical errors which you've made, over the years, and then been forced to respond to the calumny you invariably invoke in order to try to make your stance seem unsullied. --- You refuse to discuss this circuit, then you attack me personally for not doing give-and-take discussion of this circuit! --- It's not an attack, it's an observation, and it's not about this circuit in particular, it's about your fanatical need to be in control. Electronic design is all about control. Of signals. But you probably meant some sort of personal control. How does posting a circuit, and opening it for discussion, suggest control? I thought discussing circuits is what s.e.d. is for. --- Then why do you defy the group's charter by posting off-topic, irrelevant nonsense? --- You're just a crabby old git who won't discuss electronics. --- With you, since all you're interested in is fostering your agenda, the inflation of your ego. My agenda is, and always has been, to design electronics. My ego has been tuned to further that end. Electronics design requires a combination of arrogance (to believe you can do things other people can't) and humility (to avoid the thousands of possible mistakes) and compulsiveness (to get it all done, all right.) And, more than anything else, brutal honesty. Not many people an manage all that, and lots of other people don't like the people who can. There's not many things more fun than doing this with other people who know how. Especially since the whiteboard was invented. John |
#95
Posted to sci.electronics.design,rec.audio.tech
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another bizarre audio circuit
On Fri, 04 Mar 2011 11:12:39 GMT, asdf wrote:
On Wed, 02 Mar 2011 08:40:42 -0800, John Larkin wrote: I've always sort of liked the classic "GE" tape head/mic preamp circuit: ftp://jjlarkin.lmi.net/GEcircuit.jpg but it occurred to me that it might also make a nice headphone amp... ftp://jjlarkin.lmi.net/GE_headphone_amp.JPG Audio tends to be nonsense, but at least the audio guys have fun playing with circuits, whether they make a lot of sense or not. John Ironically, it looks somewhat similar to the old style fuzz face guitar effect. http://geofex.com/Article_Folders/fuzzface/fftech.htm Except that it makes distortion, and a headphone amp shouldn't! John |
#96
Posted to sci.electronics.design,rec.audio.tech
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another bizarre audio circuit
On Fri, 04 Mar 2011 06:51:30 -0800, John Larkin
wrote: On Fri, 04 Mar 2011 06:31:40 -0600, John Fields wrote: On Thu, 03 Mar 2011 15:55:19 -0800, John Larkin wrote: On Thu, 03 Mar 2011 14:44:58 -0600, John Fields wrote: On Thu, 03 Mar 2011 10:22:31 -0800, John Larkin wrote: On Thu, 03 Mar 2011 12:07:36 -0600, John Fields wrote: --- The truth _is_ you have less of an interest in discussing electronics in a give-and-take kind of way than you do in exalting yourself, so I prefer to generally opt out of any threads you infect. --- JF I didn't "infect" this thread, I started it. --- Then it was diseased from the beginning. --- So why have you posted so much cluckey blather here? --- You call it "cluckey blather" in an attempt to belittle it, I call it what it is: criticism. Criticism would have some content. --- It does, and the content accurately enumerates your foibles, which is anathema to you since you've managed to convince yourself and are trying to convince everyone else that you're perfect in every way. --- You know, something having to do with the circuit. --- There are no rules here, as you've proved by your gross abuse of the newsgroup with your legion off-topic posts, and if I choose to not comment on your circuit, that's my right. --- All you've done is whine. --- Not so. What I've done is simply point out technical errors which you've made, over the years, and then been forced to respond to the calumny you invariably invoke in order to try to make your stance seem unsullied. --- You refuse to discuss this circuit, then you attack me personally for not doing give-and-take discussion of this circuit! --- It's not an attack, it's an observation, and it's not about this circuit in particular, it's about your fanatical need to be in control. Electronic design is all about control. Of signals. But you probably meant some sort of personal control. How does posting a circuit, and opening it for discussion, suggest control? I thought discussing circuits is what s.e.d. is for. --- Then why do you defy the group's charter by posting off-topic, irrelevant nonsense? --- You're just a crabby old git who won't discuss electronics. --- With you, since all you're interested in is fostering your agenda, the inflation of your ego. My agenda is, and always has been, to design electronics. My ego has been tuned to further that end. Electronics design requires a combination of arrogance (to believe you can do things other people can't) and humility (to avoid the thousands of possible mistakes) and compulsiveness (to get it all done, all right.) And, more than anything else, brutal honesty. Not many people an manage all that, and lots of other people don't like the people who can. There's not many things more fun than doing this with other people who know how. Especially since the whiteboard was invented. John --- On the above, I'm not at odds with you except for the "brutal honesty" part which, when you're found to be in error, all of a sudden doesn't apply to you. --- JF |
#97
Posted to sci.electronics.design,rec.audio.tech
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another bizarre audio circuit
On Mar 4, 12:43*am, John Larkin
wrote: On Thu, 3 Mar 2011 19:08:38 -0800 (PST), George Herold wrote: On Mar 3, 6:49*pm, John Larkin wrote: On Thu, 3 Mar 2011 15:21:33 -0800 (PST), Bill Sloman wrote: On Mar 3, 4:12 pm, John Larkin wrote: On Thu, 3 Mar 2011 00:10:16 -0800 (PST), Bill Sloman wrote: On Mar 3, 3:32 am, John Larkin wrote: On Wed, 2 Mar 2011 17:59:58 -0800 (PST), Bill Sloman wrote: On Mar 3, 2:11 am, John Larkin wrote: On Wed, 02 Mar 2011 18:36:25 -0600, John Fields wrote: On Wed, 02 Mar 2011 08:40:42 -0800, John Larkin wrote: I've always sort of liked the classic "GE" tape head/mic preamp circuit: ftp://jjlarkin.lmi.net/GEcircuit.jpg but it occurred to me that it might also make a nice headphone amp... ftp://jjlarkin.lmi.net/GE_headphone_amp.JPG Audio tends to be nonsense, but at least the audio guys have fun playing with circuits, whether they make a lot of sense or not. John --- Even though you scorn and ridicule audio, there's nothing wrong with anyone seeking perfection there, just as there's nothing wrong with your search for perfection in the genre which pleases _you_ to pursue. So, speaking of fun, why don't you do a complete design and assign values to the circuit components and identify the semiconductors? You're not playing the game. You are sitting in the henhouse, clucking about the people who do. He's not playing your game, which involves telling John Larkin how cute his circuits are. He's not designing circuits, which is what this newsgroup is about. You aren't either. Both of you start to cluck and peck when people do design circuits. No surprise. Or is that legwork _we're_ supposed to do in order to flesh out your divine revelation? Chickenleg work! It's half the story - a few component values make it a lot easier to work out what a circuit is doing. You can't look at a circuit this simple and see what it's doing? OK, no surprise. Without the component values, it does take a moment's thought, which is wasted on a bizarre (if simple) circuit with few potential applications. Millions of the "GE" circuit have been used for decades. The mosfet hybrid is a very reasonable headphone amp. Post a circuit, doofus. You've forgotten how to do anything but whine. You are the one who complains all the time. You may have personal preferences about the nature of the threads that get started here, and the responses that get posted, but they are only of interest to you. You are welcome to demonstrate your preferences by choosing to get involved with particular threads and in your particular reactions to other responses, but your whining about the nature of those responses doesn't make the group a more attractive or rewarding environment. In the meantime, I'll post a circuit when I've got a circuit worth posting. Posting a example - without comnponent values - of a circuit that has been used in millions, for decades, doesn't strike me as a profitable use of bandwidth, but that is a personal preference. What I did was spin a signal-level bipolar circuit into a bipolar-mosfet power amp of similar topology. The resulting dynamics is very interesting. Well, not to you. John- Hide quoted text - - Show quoted text - Yeah, I didn't get the inductor part. *Do I have to spice it? *Or does it have to do with head phone dynamics. Say, and what about using the postive rail of an opamp as an output? I never heard of that. George H. Old trick. Here's a bipolar-swing version. ftp://jjlarkin.lmi.net/Opamp_boost_2.JPG A similar thing is sometimes done to boost the current of an LM317, by using its input current to drive the base of a PNP "helper" transistor. I use a variant of this circuit as a current splitter in my NMR gradient amps. I can't spell, or type, either. John- Hide quoted text - - Show quoted text - Intersesting thanks. Is there a reason not to take the feedback from the output (transistor collectors) rather than the opamp itself? George H. |
#98
Posted to sci.electronics.design,rec.audio.tech
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another bizarre audio circuit
On Fri, 4 Mar 2011 07:31:14 -0800 (PST), George Herold
wrote: On Mar 4, 12:43*am, John Larkin wrote: On Thu, 3 Mar 2011 19:08:38 -0800 (PST), George Herold wrote: On Mar 3, 6:49*pm, John Larkin wrote: On Thu, 3 Mar 2011 15:21:33 -0800 (PST), Bill Sloman wrote: On Mar 3, 4:12 pm, John Larkin wrote: On Thu, 3 Mar 2011 00:10:16 -0800 (PST), Bill Sloman wrote: On Mar 3, 3:32 am, John Larkin wrote: On Wed, 2 Mar 2011 17:59:58 -0800 (PST), Bill Sloman wrote: On Mar 3, 2:11 am, John Larkin wrote: On Wed, 02 Mar 2011 18:36:25 -0600, John Fields wrote: On Wed, 02 Mar 2011 08:40:42 -0800, John Larkin wrote: I've always sort of liked the classic "GE" tape head/mic preamp circuit: ftp://jjlarkin.lmi.net/GEcircuit.jpg but it occurred to me that it might also make a nice headphone amp... ftp://jjlarkin.lmi.net/GE_headphone_amp.JPG Audio tends to be nonsense, but at least the audio guys have fun playing with circuits, whether they make a lot of sense or not. John --- Even though you scorn and ridicule audio, there's nothing wrong with anyone seeking perfection there, just as there's nothing wrong with your search for perfection in the genre which pleases _you_ to pursue. So, speaking of fun, why don't you do a complete design and assign values to the circuit components and identify the semiconductors? You're not playing the game. You are sitting in the henhouse, clucking about the people who do. He's not playing your game, which involves telling John Larkin how cute his circuits are. He's not designing circuits, which is what this newsgroup is about. You aren't either. Both of you start to cluck and peck when people do design circuits. No surprise. Or is that legwork _we're_ supposed to do in order to flesh out your divine revelation? Chickenleg work! It's half the story - a few component values make it a lot easier to work out what a circuit is doing. You can't look at a circuit this simple and see what it's doing? OK, no surprise. Without the component values, it does take a moment's thought, which is wasted on a bizarre (if simple) circuit with few potential applications. Millions of the "GE" circuit have been used for decades. The mosfet hybrid is a very reasonable headphone amp. Post a circuit, doofus. You've forgotten how to do anything but whine. You are the one who complains all the time. You may have personal preferences about the nature of the threads that get started here, and the responses that get posted, but they are only of interest to you. You are welcome to demonstrate your preferences by choosing to get involved with particular threads and in your particular reactions to other responses, but your whining about the nature of those responses doesn't make the group a more attractive or rewarding environment. In the meantime, I'll post a circuit when I've got a circuit worth posting. Posting a example - without comnponent values - of a circuit that has been used in millions, for decades, doesn't strike me as a profitable use of bandwidth, but that is a personal preference. What I did was spin a signal-level bipolar circuit into a bipolar-mosfet power amp of similar topology. The resulting dynamics is very interesting. Well, not to you. John- Hide quoted text - - Show quoted text - Yeah, I didn't get the inductor part. *Do I have to spice it? *Or does it have to do with head phone dynamics. Say, and what about using the postive rail of an opamp as an output? I never heard of that. George H. Old trick. Here's a bipolar-swing version. ftp://jjlarkin.lmi.net/Opamp_boost_2.JPG A similar thing is sometimes done to boost the current of an LM317, by using its input current to drive the base of a PNP "helper" transistor. I use a variant of this circuit as a current splitter in my NMR gradient amps. I can't spell, or type, either. John- Hide quoted text - - Show quoted text - Intersesting thanks. Is there a reason not to take the feedback from the output (transistor collectors) rather than the opamp itself? George H. Depends on what you want to do. In my gradient amps, I want the overall box to be a current source, so I don't use any voltage feedback. The upper and lower boost transistors are replaced by precision current mirrors, and I usually cascode the opamp supply currents up into the mirrors, bacause the rail voltages tend to be high. As a boosted voltage amp, you'd generally want voltage feedback from the final output. The feedback can go into the inputs of the opamp, but I've seen cases where the feedback was applied to the *output* of the opamp. John |
#99
Posted to sci.electronics.design,rec.audio.tech
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another bizarre audio circuit
On Fri, 04 Mar 2011 09:18:28 -0600, John Fields
wrote: On Fri, 04 Mar 2011 06:51:30 -0800, John Larkin wrote: On Fri, 04 Mar 2011 06:31:40 -0600, John Fields wrote: On Thu, 03 Mar 2011 15:55:19 -0800, John Larkin wrote: On Thu, 03 Mar 2011 14:44:58 -0600, John Fields wrote: On Thu, 03 Mar 2011 10:22:31 -0800, John Larkin wrote: On Thu, 03 Mar 2011 12:07:36 -0600, John Fields wrote: --- The truth _is_ you have less of an interest in discussing electronics in a give-and-take kind of way than you do in exalting yourself, so I prefer to generally opt out of any threads you infect. --- JF I didn't "infect" this thread, I started it. --- Then it was diseased from the beginning. --- So why have you posted so much cluckey blather here? --- You call it "cluckey blather" in an attempt to belittle it, I call it what it is: criticism. Criticism would have some content. --- It does, and the content accurately enumerates your foibles, which is anathema to you since you've managed to convince yourself and are trying to convince everyone else that you're perfect in every way. --- You know, something having to do with the circuit. --- There are no rules here, as you've proved by your gross abuse of the newsgroup with your legion off-topic posts, and if I choose to not comment on your circuit, that's my right. --- All you've done is whine. --- Not so. What I've done is simply point out technical errors which you've made, over the years, and then been forced to respond to the calumny you invariably invoke in order to try to make your stance seem unsullied. --- You refuse to discuss this circuit, then you attack me personally for not doing give-and-take discussion of this circuit! --- It's not an attack, it's an observation, and it's not about this circuit in particular, it's about your fanatical need to be in control. Electronic design is all about control. Of signals. But you probably meant some sort of personal control. How does posting a circuit, and opening it for discussion, suggest control? I thought discussing circuits is what s.e.d. is for. --- Then why do you defy the group's charter by posting off-topic, irrelevant nonsense? --- You're just a crabby old git who won't discuss electronics. --- With you, since all you're interested in is fostering your agenda, the inflation of your ego. My agenda is, and always has been, to design electronics. My ego has been tuned to further that end. Electronics design requires a combination of arrogance (to believe you can do things other people can't) and humility (to avoid the thousands of possible mistakes) and compulsiveness (to get it all done, all right.) And, more than anything else, brutal honesty. Not many people an manage all that, and lots of other people don't like the people who can. There's not many things more fun than doing this with other people who know how. Especially since the whiteboard was invented. John --- On the above, I'm not at odds with you except for the "brutal honesty" part which, when you're found to be in error, all of a sudden doesn't apply to you. --- JF I make mistakes all the time, and a lot of my ideas get paved over by somebody else's ideas. I work with some *very* smart people who, in their areas, know a lot more than I do. That's part of the fun of playing with ideas. But if you want to argue over definitions, like whether something that's unboundedly large can be referred to as "infinite", that's just words, definitions, and doesn't matter. It certainly doesn't affect the electronics. A latching relay does what it does. John |
#100
Posted to sci.electronics.design,rec.audio.tech
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another bizarre audio circuit
On Thu, 3 Mar 2011 19:53:58 -0800 (PST), Fred Bloggs
wrote: On Mar 2, 5:58*pm, John Larkin wrote: On Wed, 2 Mar 2011 14:55:18 -0800 (PST), Fred Bloggs wrote: On Mar 2, 4:33 pm, John Larkin wrote: On Wed, 2 Mar 2011 12:03:38 -0800 (PST), Fred Bloggs wrote: On Mar 2, 11:40 am, John Larkin wrote: I've always sort of liked the classic "GE" tape head/mic preamp circuit: ftp://jjlarkin.lmi.net/GEcircuit.jpg but it occurred to me that it might also make a nice headphone amp... ftp://jjlarkin.lmi.net/GE_headphone_amp.JPG Audio tends to be nonsense, but at least the audio guys have fun playing with circuits, whether they make a lot of sense or not. John Bizarre??? Just a standard buffered input CE with negative feedback DC bias to stabilize the operating point against Vbe and reverse leakage collector current change with temperature- a textbook circuit... Which textbook? John- Hide quoted text - - Show quoted text - Just about any textbook that goes into bias point sensitivity analysis of transistor circuits- you remember the S- functions, mainly ICQ stability. The big three were HFE, VBE, and ICBO. Then the rest of your circuit is just ac-bypass and the shunt-series feedback for signals. I've seen it dozens of times. I bet you haven't seen the bipolar+mosfet version, with inductive pullup, used as a power amp. John- Hide quoted text - - Show quoted text - I don't see the MOSFET being all that much of a change. And as for the inductor pull-up, this just doesn't make sense for low wattage high impedance headphone loads. Your inductive reactance needs to be a good few integer multiples of the load impedance, making these things prohibitively large if not unobtainable for a headphone app- you would use far less iron/ ferrite by boost switching your supply to accommodate the output swing...guess that's why I've never seen the inductive pullup here. Of course you haven't seen this circuit befo I just invented it. But inductors were widely used as plate loads in the tube days. Tubes were expensive and had low gains, so transformers and inductors were sensible. Early transistor amps used lots of transformers, for the same reasons. John |
#101
Posted to sci.electronics.design,rec.audio.tech
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another bizarre audio circuit
On Fri, 04 Mar 2011 08:18:03 -0800, John Larkin
wrote: On Fri, 04 Mar 2011 09:18:28 -0600, John Fields wrote: On the above, I'm not at odds with you except for the "brutal honesty" part which, when you're found to be in error, all of a sudden doesn't apply to you. --- JF I make mistakes all the time, and a lot of my ideas get paved over by somebody else's ideas. I work with some *very* smart people who, in their areas, know a lot more than I do. That's part of the fun of playing with ideas. --- Apples and oranges. You're talking about who you are at work and I'm talking about who you are here; obviously two different people. --- But if you want to argue over definitions, like whether something that's unboundedly large can be referred to as "infinite", that's just words, definitions, and doesn't matter. --- Total nonsense since if words and definitions didn't matter then there'd be no purpose for language. The thing is though, that it can't be unboundedly large as long as there's something other than zero in the denominator, and if it takes any power at all to switch it, you're stuck with less than infinite gain. Approaching infinity in the limit, but never quite able to get there. --- It certainly doesn't affect the electronics. A latching relay does what it does. John --- A rose, by any other name... --- JF |
#102
Posted to sci.electronics.design,rec.audio.tech
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another bizarre audio circuit
On Fri, 04 Mar 2011 11:59:58 -0600, John Fields
wrote: On Fri, 04 Mar 2011 08:18:03 -0800, John Larkin wrote: On Fri, 04 Mar 2011 09:18:28 -0600, John Fields wrote: On the above, I'm not at odds with you except for the "brutal honesty" part which, when you're found to be in error, all of a sudden doesn't apply to you. --- JF I make mistakes all the time, and a lot of my ideas get paved over by somebody else's ideas. I work with some *very* smart people who, in their areas, know a lot more than I do. That's part of the fun of playing with ideas. --- Apples and oranges. You're talking about who you are at work and I'm talking about who you are here; obviously two different people. It's a newsgroup, not life. --- But if you want to argue over definitions, like whether something that's unboundedly large can be referred to as "infinite", that's just words, definitions, and doesn't matter. --- Total nonsense since if words and definitions didn't matter then there'd be no purpose for language. The thing is though, that it can't be unboundedly large as long as there's something other than zero in the denominator, and if it takes any power at all to switch it, you're stuck with less than infinite gain. What is infinity/1 ? You seem to be arguing that nothing can ever be unboundedly large since any number can be divided by 1. Approaching infinity in the limit, but never quite able to get there. That's the way infinity tends to work. I was taught that infinity isn't a number, it's a limit. ( Lim (1/x) as x0 ) infinity which works well enough in engineering. John |
#103
Posted to sci.electronics.design,rec.audio.tech
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another bizarre audio circuit
On Mar 4, 12:59*pm, Chieftain of the Carpet Crawlers
wrote: On Fri, 4 Mar 2011 02:35:52 -0800 (PST), Bill Sloman wrote: Not really. Most of the people who post here haven't used a 555 for years. * You do not know that, A similar thread to this a few years ago prompted a bunch of responses saying exactly that, from people with a history in this group. and you saying it does not make it true. Obviously not. It does happen to be true, none-the-less. * You are an idiot to think so. You may think so. -- Bill Sloman, Nijmegen |
#104
Posted to sci.electronics.design,rec.audio.tech
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another bizarre audio circuit
On Fri, 04 Mar 2011 10:15:02 -0800, John Larkin
wrote: On Fri, 04 Mar 2011 11:59:58 -0600, John Fields wrote: On Fri, 04 Mar 2011 08:18:03 -0800, John Larkin wrote: On Fri, 04 Mar 2011 09:18:28 -0600, John Fields wrote: On the above, I'm not at odds with you except for the "brutal honesty" part which, when you're found to be in error, all of a sudden doesn't apply to you. --- JF I make mistakes all the time, and a lot of my ideas get paved over by somebody else's ideas. I work with some *very* smart people who, in their areas, know a lot more than I do. That's part of the fun of playing with ideas. --- Apples and oranges. You're talking about who you are at work and I'm talking about who you are here; obviously two different people. It's a newsgroup, not life. --- Since when is interacting with people not life? --- But if you want to argue over definitions, like whether something that's unboundedly large can be referred to as "infinite", that's just words, definitions, and doesn't matter. --- Total nonsense since if words and definitions didn't matter then there'd be no purpose for language. The thing is though, that it can't be unboundedly large as long as there's something other than zero in the denominator, and if it takes any power at all to switch it, you're stuck with less than infinite gain. What is infinity/1 ? You seem to be arguing that nothing can ever be unboundedly large since any number can be divided by 1. --- Huh??? I said something _other_ than zero in the denominator --- Approaching infinity in the limit, but never quite able to get there. That's the way infinity tends to work. I was taught that infinity isn't a number, it's a limit. --- If that's what you were taught, then you ought to know that the gain of a latching relay can never be infinite. --- ( Lim (1/x) as x0 ) infinity which works well enough in engineering. --- Whatever... --- JF |
#105
Posted to sci.electronics.design,rec.audio.tech
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another bizarre audio circuit
John Larkin wrote:
On Fri, 4 Mar 2011 07:31:14 -0800 (PST), George Herold wrote: On Mar 4, 12:43 am, John Larkin wrote: On Thu, 3 Mar 2011 19:08:38 -0800 (PST), George Herold wrote: On Mar 3, 6:49 pm, John Larkin wrote: On Thu, 3 Mar 2011 15:21:33 -0800 (PST), Bill Sloman wrote: On Mar 3, 4:12 pm, John Larkin wrote: On Thu, 3 Mar 2011 00:10:16 -0800 (PST), Bill Sloman wrote: On Mar 3, 3:32 am, John Larkin wrote: On Wed, 2 Mar 2011 17:59:58 -0800 (PST), Bill Sloman wrote: On Mar 3, 2:11 am, John Larkin wrote: On Wed, 02 Mar 2011 18:36:25 -0600, John Fields wrote: On Wed, 02 Mar 2011 08:40:42 -0800, John Larkin wrote: I've always sort of liked the classic "GE" tape head/mic preamp circuit: ftp://jjlarkin.lmi.net/GEcircuit.jpg but it occurred to me that it might also make a nice headphone amp... ftp://jjlarkin.lmi.net/GE_headphone_amp.JPG Audio tends to be nonsense, but at least the audio guys have fun playing with circuits, whether they make a lot of sense or not. John --- Even though you scorn and ridicule audio, there's nothing wrong with anyone seeking perfection there, just as there's nothing wrong with your search for perfection in the genre which pleases _you_ to pursue. So, speaking of fun, why don't you do a complete design and assign values to the circuit components and identify the semiconductors? You're not playing the game. You are sitting in the henhouse, clucking about the people who do. He's not playing your game, which involves telling John Larkin how cute his circuits are. He's not designing circuits, which is what this newsgroup is about. You aren't either. Both of you start to cluck and peck when people do design circuits. No surprise. Or is that legwork _we're_ supposed to do in order to flesh out your divine revelation? Chickenleg work! It's half the story - a few component values make it a lot easier to work out what a circuit is doing. You can't look at a circuit this simple and see what it's doing? OK, no surprise. Without the component values, it does take a moment's thought, which is wasted on a bizarre (if simple) circuit with few potential applications. Millions of the "GE" circuit have been used for decades. The mosfet hybrid is a very reasonable headphone amp. Post a circuit, doofus. You've forgotten how to do anything but whine. You are the one who complains all the time. You may have personal preferences about the nature of the threads that get started here, and the responses that get posted, but they are only of interest to you. You are welcome to demonstrate your preferences by choosing to get involved with particular threads and in your particular reactions to other responses, but your whining about the nature of those responses doesn't make the group a more attractive or rewarding environment. In the meantime, I'll post a circuit when I've got a circuit worth posting. Posting a example - without comnponent values - of a circuit that has been used in millions, for decades, doesn't strike me as a profitable use of bandwidth, but that is a personal preference. What I did was spin a signal-level bipolar circuit into a bipolar-mosfet power amp of similar topology. The resulting dynamics is very interesting. Well, not to you. John- Hide quoted text - - Show quoted text - Yeah, I didn't get the inductor part. Do I have to spice it? Or does it have to do with head phone dynamics. Say, and what about using the postive rail of an opamp as an output? I never heard of that. George H. Old trick. Here's a bipolar-swing version. ftp://jjlarkin.lmi.net/Opamp_boost_2.JPG A similar thing is sometimes done to boost the current of an LM317, by using its input current to drive the base of a PNP "helper" transistor. I use a variant of this circuit as a current splitter in my NMR gradient amps. I can't spell, or type, either. John- Hide quoted text - - Show quoted text - Intersesting thanks. Is there a reason not to take the feedback from the output (transistor collectors) rather than the opamp itself? George H. Depends on what you want to do. In my gradient amps, I want the overall box to be a current source, so I don't use any voltage feedback. The upper and lower boost transistors are replaced by precision current mirrors, and I usually cascode the opamp supply currents up into the mirrors, bacause the rail voltages tend to be high. As a boosted voltage amp, you'd generally want voltage feedback from the final output. The feedback can go into the inputs of the opamp, but I've seen cases where the feedback was applied to the *output* of the opamp. John Having some feedback to the output is a win, because the feedback goes both ways--the op amp can provide some of the output. It's also a bit quicker for large signal stuff, because the error current goes straight out the supply leads without going through the frequency compensation stuff in the front end. Of course that complicates the overall frequency compensation of the amp. Making composite amps with decent settling behaviour can be pretty tough. Cheers Phil Hobbs -- Dr Philip C D Hobbs Principal ElectroOptical Innovations 55 Orchard Rd Briarcliff Manor NY 10510 845-480-2058 email: hobbs (atsign) electrooptical (period) net http://electrooptical.net |
#106
Posted to sci.electronics.design,rec.audio.tech
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another bizarre audio circuit
John Fields wrote:
On Fri, 04 Mar 2011 08:18:03 -0800, John Larkin wrote: On Fri, 04 Mar 2011 09:18:28 -0600, John Fields wrote: On the above, I'm not at odds with you except for the "brutal honesty" part which, when you're found to be in error, all of a sudden doesn't apply to you. --- JF I make mistakes all the time, and a lot of my ideas get paved over by somebody else's ideas. I work with some *very* smart people who, in their areas, know a lot more than I do. That's part of the fun of playing with ideas. --- Apples and oranges. You're talking about who you are at work and I'm talking about who you are here; obviously two different people. --- But if you want to argue over definitions, like whether something that's unboundedly large can be referred to as "infinite", that's just words, definitions, and doesn't matter. --- Total nonsense since if words and definitions didn't matter then there'd be no purpose for language. The thing is though, that it can't be unboundedly large as long as there's something other than zero in the denominator, and if it takes any power at all to switch it, you're stuck with less than infinite gain. Approaching infinity in the limit, but never quite able to get there. --- It certainly doesn't affect the electronics. A latching relay does what it does. John --- A rose, by any other name... --- JF Can we please declare a weekend moratorium on ****ing contests? Pretty please? Cheers Phil Hobbs -- Dr Philip C D Hobbs Principal ElectroOptical Innovations 55 Orchard Rd Briarcliff Manor NY 10510 845-480-2058 email: hobbs (atsign) electrooptical (period) net http://electrooptical.net |
#107
Posted to sci.electronics.design,rec.audio.tech
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another bizarre audio circuit
On Fri, 04 Mar 2011 15:03:20 -0500, Phil Hobbs
wrote: Can we please declare a weekend moratorium on ****ing contests? Pretty please? Cheers Phil Hobbs --- Works for me! :-) --- JF |
#108
Posted to sci.electronics.design,rec.audio.tech
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another bizarre audio circuit
On Mar 4, 12:54*pm, John Larkin
wrote: On Thu, 3 Mar 2011 19:53:58 -0800 (PST), Fred Bloggs wrote: On Mar 2, 5:58 pm, John Larkin wrote: On Wed, 2 Mar 2011 14:55:18 -0800 (PST), Fred Bloggs wrote: On Mar 2, 4:33 pm, John Larkin wrote: On Wed, 2 Mar 2011 12:03:38 -0800 (PST), Fred Bloggs wrote: On Mar 2, 11:40 am, John Larkin wrote: I've always sort of liked the classic "GE" tape head/mic preamp circuit: ftp://jjlarkin.lmi.net/GEcircuit.jpg but it occurred to me that it might also make a nice headphone amp... ftp://jjlarkin.lmi.net/GE_headphone_amp.JPG Audio tends to be nonsense, but at least the audio guys have fun playing with circuits, whether they make a lot of sense or not. John Bizarre??? Just a standard buffered input CE with negative feedback DC bias to stabilize the operating point against Vbe and reverse leakage collector current change with temperature- a textbook circuit... Which textbook? John- Hide quoted text - - Show quoted text - Just about any textbook that goes into bias point sensitivity analysis of transistor circuits- you remember the S- functions, mainly ICQ stability. The big three were HFE, VBE, and ICBO. Then the rest of your circuit is just ac-bypass and the shunt-series feedback for signals. I've seen it dozens of times. I bet you haven't seen the bipolar+mosfet version, with inductive pullup, used as a power amp. John- Hide quoted text - - Show quoted text - I don't see the MOSFET being all that much of a change. And as for the inductor pull-up, this just doesn't make sense for low wattage high impedance headphone loads. Your inductive reactance needs to be a good few integer multiples of the load impedance, making these things prohibitively large if not unobtainable for a headphone app- you would use far less iron/ ferrite by boost switching your supply to accommodate the output swing...guess that's why I've never seen the inductive pullup here. Of course you haven't seen this circuit befo I just invented it. But inductors were widely used as plate loads in the tube days. Tubes were expensive and had low gains, so transformers and inductors were sensible. Early transistor amps used lots of transformers, for the same reasons. John- Hide quoted text - - Show quoted text - I thinking you are confusing your app with peaking coils which were one of several techniques used to broadband the amplifier- that's a totally different application and it was practical because the reactance was only important in the 10's KHz band or higher- this is not the case for a 20-20K Hz headphone circuit. |
#109
Posted to sci.electronics.design,rec.audio.tech
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another bizarre audio circuit
On Thu, 03 Mar 2011 21:14:26 -0800, John Larkin
wrote: On Thu, 03 Mar 2011 18:04:33 -0800, Chieftain of the Carpet Crawlers wrote: On Thu, 03 Mar 2011 08:59:38 -0800, John Larkin wrote: Stop whining and clucking about personalities Stop with the retarded colloquialisms (or attempts at them). You stupid ****. That is about as plain as it gets. You show with nearly every post just how little a man you are. If you even get that qualification. Your personality is that of a circus flea. Dance, mother****er. The thing you guys have in common is that you suck at electronics, and you know it. That pretty much explains everything. ....except why they are here. |
#110
Posted to sci.electronics.design,rec.audio.tech
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another bizarre audio circuit
On Fri, 04 Mar 2011 17:57:05 -0600, "
wrote: On Thu, 03 Mar 2011 21:14:26 -0800, John Larkin wrote: On Thu, 03 Mar 2011 18:04:33 -0800, Chieftain of the Carpet Crawlers wrote: On Thu, 03 Mar 2011 08:59:38 -0800, John Larkin wrote: Stop whining and clucking about personalities Stop with the retarded colloquialisms (or attempts at them). You stupid ****. That is about as plain as it gets. You show with nearly every post just how little a man you are. If you even get that qualification. Your personality is that of a circus flea. Dance, mother****er. The thing you guys have in common is that you suck at electronics, and you know it. That pretty much explains everything. ...except why they are here. Oh. Maybe they suck at electronics and *don't* know it. John |
#111
Posted to sci.electronics.design,rec.audio.tech
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another bizarre audio circuit
On Fri, 04 Mar 2011 16:22:58 -0800, John Larkin
wrote: On Fri, 04 Mar 2011 17:57:05 -0600, " wrote: On Thu, 03 Mar 2011 21:14:26 -0800, John Larkin wrote: On Thu, 03 Mar 2011 18:04:33 -0800, Chieftain of the Carpet Crawlers g wrote: On Thu, 03 Mar 2011 08:59:38 -0800, John Larkin wrote: Stop whining and clucking about personalities Stop with the retarded colloquialisms (or attempts at them). You stupid ****. That is about as plain as it gets. You show with nearly every post just how little a man you are. If you even get that qualification. Your personality is that of a circus flea. Dance, mother****er. The thing you guys have in common is that you suck at electronics, and you know it. That pretty much explains everything. ...except why they are here. Oh. Maybe they suck at electronics and *don't* know it. Ya, think maybe? |
#112
Posted to sci.electronics.design,rec.audio.tech
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another bizarre audio circuit
On Mar 4, 3:01*pm, Phil Hobbs
wrote: John Larkin wrote: On Fri, 4 Mar 2011 07:31:14 -0800 (PST), George Herold *wrote: On Mar 4, 12:43 am, John Larkin *wrote: On Thu, 3 Mar 2011 19:08:38 -0800 (PST), George Herold *wrote: On Mar 3, 6:49 pm, John Larkin *wrote: On Thu, 3 Mar 2011 15:21:33 -0800 (PST), Bill Sloman *wrote: On Mar 3, 4:12 pm, John Larkin *wrote: On Thu, 3 Mar 2011 00:10:16 -0800 (PST), Bill Sloman *wrote: On Mar 3, 3:32 am, John Larkin *wrote: On Wed, 2 Mar 2011 17:59:58 -0800 (PST), Bill Sloman *wrote: On Mar 3, 2:11 am, John Larkin *wrote: On Wed, 02 Mar 2011 18:36:25 -0600, John Fields *wrote: On Wed, 02 Mar 2011 08:40:42 -0800, John Larkin *wrote: I've always sort of liked the classic "GE" tape head/mic preamp circuit: ftp://jjlarkin.lmi.net/GEcircuit.jpg but it occurred to me that it might also make a nice headphone amp... ftp://jjlarkin.lmi.net/GE_headphone_amp.JPG Audio tends to be nonsense, but at least the audio guys have fun playing with circuits, whether they make a lot of sense or not. John --- Even though you scorn and ridicule audio, there's nothing wrong with anyone seeking perfection there, just as there's nothing wrong with your search for perfection in the genre which pleases _you_ to pursue. So, speaking of fun, why don't you do a complete design and assign values to the circuit components and identify the semiconductors? You're not playing the game. You are sitting in the henhouse, clucking about the people who do. He's not playing your game, which involves telling John Larkin how cute his circuits are. He's not designing circuits, which is what this newsgroup is about. You aren't either. Both of you start to cluck and peck when people do design circuits. No surprise. Or is that legwork _we're_ supposed to do in order to flesh out your divine revelation? Chickenleg work! It's half the story - a few component values make it a lot easier to work out what a circuit is doing. You can't look at a circuit this simple and see what it's doing? OK, no surprise. Without the component values, it does take a moment's thought, which is wasted on a bizarre (if simple) circuit with few potential applications. Millions of the "GE" circuit have been used for decades. The mosfet hybrid is a very reasonable headphone amp. Post a circuit, doofus. You've forgotten how to do anything but whine. You are the one who complains all the time. You may have personal preferences about the nature of the threads that get started here, and the responses that get posted, but they are only of interest to you. You are welcome to demonstrate your preferences by choosing to get involved with particular threads and in your particular reactions to other responses, but your whining about the nature of those responses doesn't make the group a more attractive or rewarding environment. In the meantime, I'll post a circuit when I've got a circuit worth posting. Posting a example - without comnponent values - of a circuit that has been used in millions, for decades, doesn't strike me as a profitable use of bandwidth, but that is a personal preference. What I did was spin a signal-level bipolar circuit into a bipolar-mosfet power amp of similar topology. The resulting dynamics is very interesting. Well, not to you. John- Hide quoted text - - Show quoted text - Yeah, I didn't get the inductor part. *Do I have to spice it? *Or does it have to do with head phone dynamics. Say, and what about using the postive rail of an opamp as an output? I never heard of that. George H. Old trick. Here's a bipolar-swing version. ftp://jjlarkin.lmi.net/Opamp_boost_2.JPG A similar thing is sometimes done to boost the current of an LM317, by using its input current to drive the base of a PNP "helper" transistor. I use a variant of this circuit as a current splitter in my NMR gradient amps. I can't spell, or type, either. John- Hide quoted text - - Show quoted text - Intersesting thanks. *Is there a reason not to take the feedback from the output (transistor collectors) rather than the opamp itself? George H. Depends on what you want to do. In my gradient amps, I want the overall box to be a current source, so I don't use any voltage feedback. The upper and lower boost transistors are replaced by precision current mirrors, and I usually cascode the opamp supply currents up into the mirrors, bacause the rail voltages tend to be high. As a boosted voltage amp, you'd generally want voltage feedback from the final output. The feedback can go into the inputs of the opamp, but I've seen cases where the feedback was applied to the *output* of the opamp. John Having some feedback to the output is a win, because the feedback goes both ways--the op amp can provide some of the output. *It's also a bit quicker for large signal stuff, because the error current goes straight out the supply leads without going through the frequency compensation stuff in the front end. *Of course that complicates the overall frequency compensation of the amp. Yeah it seems like you can get gob's of current out of it. You're not stuck with what the opamp can supply. There might be issues near zero. So I think you're suggesting included John's R6 and taking the feedback from after that. (At least that's how I drew it.) Making composite amps with decent settling behaviour can be pretty tough. Well if it was easy I would have already heard about it. George H. Cheers Phil Hobbs -- Dr Philip C D Hobbs Principal ElectroOptical Innovations 55 Orchard Rd Briarcliff Manor NY 10510 845-480-2058 email: hobbs (atsign) electrooptical (period) nethttp://electrooptical.net- Hide quoted text - - Show quoted text - |
#113
Posted to sci.electronics.design,rec.audio.tech
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another bizarre audio circuit
On Fri, 04 Mar 2011 10:15:02 -0800, John Larkin
wrote: It's a newsgroup, not life. You're a newsgroup abuser, not a man. |
#114
Posted to sci.electronics.design,rec.audio.tech
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another bizarre audio circuit
On Fri, 04 Mar 2011 18:11:07 -0800, TheQuickBrownFox
wrote: On Fri, 04 Mar 2011 10:15:02 -0800, John Larkin wrote: It's a newsgroup, not life. You're a newsgroup abuser, not a man. Write to your congresswoman. John |
#115
Posted to sci.electronics.design,rec.audio.tech
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another bizarre audio circuit
On Fri, 4 Mar 2011 10:56:32 -0800 (PST), Bill Sloman
wrote: On Mar 4, 12:59*pm, Chieftain of the Carpet Crawlers wrote: On Fri, 4 Mar 2011 02:35:52 -0800 (PST), Bill Sloman wrote: Not really. Most of the people who post here haven't used a 555 for years. * You do not know that, A similar thread to this a few years ago prompted a bunch of responses saying exactly that, from people with a history in this group. Bull****. That is what YOU would have liked them to have said. Essentially, you have proven nothing except that fact that you do NOT know what ANY others think. and you saying it does not make it true. Obviously not. It does happen to be true, none-the-less. Obviously not, idiot. You are 100% convoluted, none-the-less. * You are an idiot to think so. You may think so. Actually, me pegging you as an idiot is far more accurate than you pegging all the members of the group (and then some) as thinking one way or the other about a given topic. You are about as clueless as any man can get. |
#116
Posted to sci.electronics.design,rec.audio.tech
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another bizarre audio circuit
On Fri, 04 Mar 2011 15:03:20 -0500, Phil Hobbs
wrote: John Fields wrote: On Fri, 04 Mar 2011 08:18:03 -0800, John Larkin wrote: On Fri, 04 Mar 2011 09:18:28 -0600, John Fields wrote: On the above, I'm not at odds with you except for the "brutal honesty" part which, when you're found to be in error, all of a sudden doesn't apply to you. --- JF I make mistakes all the time, and a lot of my ideas get paved over by somebody else's ideas. I work with some *very* smart people who, in their areas, know a lot more than I do. That's part of the fun of playing with ideas. --- Apples and oranges. You're talking about who you are at work and I'm talking about who you are here; obviously two different people. --- But if you want to argue over definitions, like whether something that's unboundedly large can be referred to as "infinite", that's just words, definitions, and doesn't matter. --- Total nonsense since if words and definitions didn't matter then there'd be no purpose for language. The thing is though, that it can't be unboundedly large as long as there's something other than zero in the denominator, and if it takes any power at all to switch it, you're stuck with less than infinite gain. Approaching infinity in the limit, but never quite able to get there. --- It certainly doesn't affect the electronics. A latching relay does what it does. John --- A rose, by any other name... --- JF Can we please declare a weekend moratorium on ****ing contests? Pretty please? Cheers Phil Hobbs I can guarantee you that Larkin is the only asshole in the group that cannot comply. For one thing, that is NOT what JF is doing. Larking would like to think that he could win a ****ing contest, but he falls short of the requisite needs of being a man, and having a dick. The closest he comes to having a dick is the fact that he is typically a dickhead. |
#117
Posted to sci.electronics.design,rec.audio.tech
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another bizarre audio circuit
On Mar 5, 3:22*am, Chieftain of the Carpet Crawlers
wrote: On Fri, 4 Mar 2011 10:56:32 -0800 (PST), Bill Sloman wrote: On Mar 4, 12:59 pm, Chieftain of the Carpet Crawlers wrote: On Fri, 4 Mar 2011 02:35:52 -0800 (PST), Bill Sloman wrote: Not really. Most of the people who post here haven't used a 555 for years. You do not know that, A similar thread to this a few years ago prompted a bunch of responses saying exactly that, from people with a history in this group. * Bull****. That is what YOU would have liked them to have said. Dream on. If you had any credibility I'd find the thread, but since it's you, why should I bother? * Essentially, you have proven nothing except that fact that you do NOT know what ANY others think. I haven't bothered to prove anything. I've just made an assertion. It happens to be a correct assertion, but you are too dim to realise this, and too low in the pecking order for your opinion to matter. and you saying it does not make it true. Obviously not. It does happen to be true, none-the-less. * Obviously not, idiot. *You are 100% convoluted, none-the-less. You are an idiot to think so. You may think so. * Actually, me pegging you as an idiot is far more accurate than you pegging all the members of the group (and then some) as thinking one way or the other about a given topic. *You are about as clueless as any man can get. Do go on. This group in short on good jokes, and you make a pretty good substitute. -- Bill Sloman, Nijmegen |
#118
Posted to sci.electronics.design,rec.audio.tech
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another bizarre audio circuit
On Fri, 4 Mar 2011 19:35:32 -0800 (PST), Bill Sloman
wrote: and too low in the pecking order Sorry cast boy, but if we are declaring levels of attainment and awareness here, you would certainly be the loser against me. You don't even know what a 555 timer IC is for, much less the fact that it is still used. Far more than you are willing to believe, since it proves you wrong. And you are... both wrong AND the loser. Bye. |
#119
Posted to sci.electronics.design,rec.audio.tech
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another bizarre audio circuit
On Fri, 4 Mar 2011 14:23:17 -0800 (PST), Fred Bloggs
wrote: On Mar 4, 12:54*pm, John Larkin wrote: On Thu, 3 Mar 2011 19:53:58 -0800 (PST), Fred Bloggs wrote: On Mar 2, 5:58 pm, John Larkin wrote: On Wed, 2 Mar 2011 14:55:18 -0800 (PST), Fred Bloggs wrote: On Mar 2, 4:33 pm, John Larkin wrote: On Wed, 2 Mar 2011 12:03:38 -0800 (PST), Fred Bloggs wrote: On Mar 2, 11:40 am, John Larkin wrote: I've always sort of liked the classic "GE" tape head/mic preamp circuit: ftp://jjlarkin.lmi.net/GEcircuit.jpg but it occurred to me that it might also make a nice headphone amp... ftp://jjlarkin.lmi.net/GE_headphone_amp.JPG Audio tends to be nonsense, but at least the audio guys have fun playing with circuits, whether they make a lot of sense or not. John Bizarre??? Just a standard buffered input CE with negative feedback DC bias to stabilize the operating point against Vbe and reverse leakage collector current change with temperature- a textbook circuit... Which textbook? John- Hide quoted text - - Show quoted text - Just about any textbook that goes into bias point sensitivity analysis of transistor circuits- you remember the S- functions, mainly ICQ stability. The big three were HFE, VBE, and ICBO. Then the rest of your circuit is just ac-bypass and the shunt-series feedback for signals. I've seen it dozens of times. I bet you haven't seen the bipolar+mosfet version, with inductive pullup, used as a power amp. John- Hide quoted text - - Show quoted text - I don't see the MOSFET being all that much of a change. And as for the inductor pull-up, this just doesn't make sense for low wattage high impedance headphone loads. Your inductive reactance needs to be a good few integer multiples of the load impedance, making these things prohibitively large if not unobtainable for a headphone app- you would use far less iron/ ferrite by boost switching your supply to accommodate the output swing...guess that's why I've never seen the inductive pullup here. Of course you haven't seen this circuit befo I just invented it. But inductors were widely used as plate loads in the tube days. Tubes were expensive and had low gains, so transformers and inductors were sensible. Early transistor amps used lots of transformers, for the same reasons. John- Hide quoted text - - Show quoted text - I thinking you are confusing your app with peaking coils which were one of several techniques used to broadband the amplifier- that's a totally different application and it was practical because the reactance was only important in the 10's KHz band or higher- this is not the case for a 20-20K Hz headphone circuit. Am not! ftp://jjlarkin.lmi.net/Chokes.JPG John |
#120
Posted to sci.electronics.design,rec.audio.tech
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another bizarre audio circuit
On Fri, 04 Mar 2011 18:27:35 -0800, TheQuickBrownFox
wrote: On Fri, 04 Mar 2011 15:03:20 -0500, Phil Hobbs wrote: John Fields wrote: On Fri, 04 Mar 2011 08:18:03 -0800, John Larkin wrote: On Fri, 04 Mar 2011 09:18:28 -0600, John Fields wrote: On the above, I'm not at odds with you except for the "brutal honesty" part which, when you're found to be in error, all of a sudden doesn't apply to you. --- JF I make mistakes all the time, and a lot of my ideas get paved over by somebody else's ideas. I work with some *very* smart people who, in their areas, know a lot more than I do. That's part of the fun of playing with ideas. --- Apples and oranges. You're talking about who you are at work and I'm talking about who you are here; obviously two different people. --- But if you want to argue over definitions, like whether something that's unboundedly large can be referred to as "infinite", that's just words, definitions, and doesn't matter. --- Total nonsense since if words and definitions didn't matter then there'd be no purpose for language. The thing is though, that it can't be unboundedly large as long as there's something other than zero in the denominator, and if it takes any power at all to switch it, you're stuck with less than infinite gain. Approaching infinity in the limit, but never quite able to get there. --- It certainly doesn't affect the electronics. A latching relay does what it does. John --- A rose, by any other name... --- JF Can we please declare a weekend moratorium on ****ing contests? Pretty please? Cheers Phil Hobbs I can guarantee you that Larkin is the only asshole in the group that cannot comply. Hilarious. And very unclear on the concept. John |
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