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#41
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And there's where I get left behind...
Wouldn't constant phase shift mean VARYING time shift across the spectrum and everything goes to hell in a handbucketbrigadedevice? Yes. Think of it as a magnitude compensated first derivative of the signal WRT time. I'm going to make one comment, and then let it drop, because I don't want to get involved in a technical tsuris. There is a difference between true delay (such as recording a signal and playing it back later) and what I call "envelope shift" (what most people call group delay). I find the whole issue thoroughly confusing, and wish someone would study it carefully and thoroughly (if no one has already) and publish an article on it. |
#42
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Bob Pit wrote:
Hi I am not very familiar with CoolEdit and I want to playback my voice (or any mp3 file) with a 90 degree phase offset between the 2 channels/speakers. It must be easy but how do you do this? Thanks Bob Ultrafunk makes a phase plugin. Don't remember if it's ActiveX or VST, nor can I vouch for it beyond the demo phase. -- Les Cargill |
#43
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Bob Cain wrote:
Phil Allison wrote: AFAIK there is no way to produce a quadrature version of a given audio signal. Then modify what you know. Bob Aren't the two elements of an X/Y pair roughly +/-90 degrees with respect to each other? That's not exactly "quadrature" per se... i think of quadrature as more 'a discrete transducer kinda thing.... -- Les Cargill |
#44
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"Les Cargill" wrote in message
m Aren't the two elements of an X/Y pair roughly +/-90 degrees with respect to each other? Nope. Intensity stereo has outputs that are perfectly in phase, and differ only in amplitude. |
#45
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Les Cargill wrote: Bob Cain wrote: Phil Allison wrote: AFAIK there is no way to produce a quadrature version of a given audio signal. Then modify what you know. Bob Aren't the two elements of an X/Y pair roughly +/-90 degrees with respect to each other? That's a different kind of angle, a spatial one. It's a measure of the direction in which they point. The kind of angle we are talking about here is a time delay in a signal measured as a fraction of a cycle at any given frequency. Quadrature is just short for 90 degrees or pi/4 in radians and this is measured, again, for any given frequency as a portion of it's cycle (360 degrees or 2*pi radian per cycle.) This means that the time an angle represents varies with the frequency. Bob -- "Things should be described as simply as possible, but no simpler." A. Einstein |
#46
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Bob Cain wrote:
Les Cargill wrote: Bob Cain wrote: Phil Allison wrote: AFAIK there is no way to produce a quadrature version of a given audio signal. Then modify what you know. Bob Aren't the two elements of an X/Y pair roughly +/-90 degrees with respect to each other? That's a different kind of angle, a spatial one. I know it's a sorta dumb question, but a phase meter shows a non-zero signal 'twixt 'em. Er, at least one phase meter I've seen does, anyway. It's a measure of the direction in which they point. The kind of angle we are talking about here is a time delay in a signal measured as a fraction of a cycle at any given frequency. Right. The phasor angle of, say an RC network at a given f. Quadrature is just short for 90 degrees or pi/4 in radians and this is measured, again, for any given frequency as a portion of it's cycle (360 degrees or 2*pi radian per cycle.) This means that the time an angle represents varies with the frequency. I'm familiar with it Bob -- Les Cargilll |
#47
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Arny Krueger wrote:
"Les Cargill" wrote in message m Aren't the two elements of an X/Y pair roughly +/-90 degrees with respect to each other? Nope. Intensity stereo has outputs that are perfectly in phase, and differ only in amplitude. Oh, that's right. *Smacks forehead*. So phase meters don't just measure phase alone, then? -- Les Cargill |
#48
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"Les Cargill" wrote in message
om Arny Krueger wrote: "Les Cargill" wrote in message m Aren't the two elements of an X/Y pair roughly +/-90 degrees with respect to each other? Nope. Intensity stereo has outputs that are perfectly in phase, and differ only in amplitude. Oh, that's right. *Smacks forehead*. I was doing a similar head smack about a week ago when I started looking at some recordings I made with a Rode NT4. I found that if I took a segment of audio from both channels and normalized them, the amplitude lines would literally sit on top of each other +/- about 5 microseconds, even at the edge of the stage. This means that the fit was not exactly perfect, just really darn close. My take on the NT4 is that it is far more precise than than say, my "spider's nest" XY mic made of two matched MXL603s in shock mounts attached to a $9.95 mic bar I picked up on eBay. My MXL603 spider's nest is in turn a lot more precise than another contrivance I tried , which was made up from Audix OM6s with the pop filter balls still in place (I won't make that mistake again!). So phase meters don't just measure phase alone, then? Details, please? |
#49
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Bob Cain wrote: Quadrature is just short for 90 degrees or pi/4 in radians ... Oops. No coffee yet. Make that pi/2 radians. Bob -- "Things should be described as simply as possible, but no simpler." A. Einstein |
#50
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Les Cargill wrote: I know it's a sorta dumb question, but a phase meter shows a non-zero signal 'twixt 'em. Er, at least one phase meter I've seen does, anyway. If they were perfectly coincident and perfectly cardiod at all frequencies there would be no phase difference between them but... Bob -- "Things should be described as simply as possible, but no simpler." A. Einstein |
#51
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Arny Krueger wrote:
"Les Cargill" wrote in message om Arny Krueger wrote: "Les Cargill" wrote in message .com Aren't the two elements of an X/Y pair roughly +/-90 degrees with respect to each other? Nope. Intensity stereo has outputs that are perfectly in phase, and differ only in amplitude. Oh, that's right. *Smacks forehead*. I was doing a similar head smack about a week ago when I started looking at some recordings I made with a Rode NT4. I found that if I took a segment of audio from both channels and normalized them, the amplitude lines would literally sit on top of each other +/- about 5 microseconds, even at the edge of the stage. This means that the fit was not exactly perfect, just really darn close. My take on the NT4 is that it is far more precise than than say, my "spider's nest" XY mic made of two matched MXL603s in shock mounts attached to a $9.95 mic bar I picked up on eBay. My MXL603 spider's nest is in turn a lot more precise than another contrivance I tried , which was made up from Audix OM6s with the pop filter balls still in place (I won't make that mistake again!). So phase meters don't just measure phase alone, then? Details, please? I am somewhat working from memory, but the demo of the phase plugin (Ultrafunk?) I tried showed a non-zero phase difference between L&R on an X/Y pair ( used for drum overheads). This was done with a stereo bar, mics as close to 90% as I could get 'em - centers of elements (603s or SM81) about 3/4" apart. But in that case, there would have been a small linear difference between the wavefront arrival at each element. -- Les Cargill |
#52
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"Les Cargill" wrote in message
om Arny Krueger wrote: "Les Cargill" wrote in message om Arny Krueger wrote: "Les Cargill" wrote in message m Aren't the two elements of an X/Y pair roughly +/-90 degrees with respect to each other? Nope. Intensity stereo has outputs that are perfectly in phase, and differ only in amplitude. Oh, that's right. *Smacks forehead*. I was doing a similar head smack about a week ago when I started looking at some recordings I made with a Rode NT4. I found that if I took a segment of audio from both channels and normalized them, the amplitude lines would literally sit on top of each other +/- about 5 microseconds, even at the edge of the stage. This means that the fit was not exactly perfect, just really darn close. My take on the NT4 is that it is far more precise than than say, my "spider's nest" XY mic made of two matched MXL603s in shock mounts attached to a $9.95 mic bar I picked up on eBay. My MXL603 spider's nest is in turn a lot more precise than another contrivance I tried , which was made up from Audix OM6s with the pop filter balls still in place (I won't make that mistake again!). So phase meters don't just measure phase alone, then? Details, please? I am somewhat working from memory, but the demo of the phase plugin (Ultrafunk?) I tried showed a non-zero phase difference between L&R on an X/Y pair ( used for drum overheads). This was done with a stereo bar, mics as close to 90% as I could get 'em - centers of elements (603s or SM81) about 3/4" apart. But in that case, there would have been a small linear difference between the wavefront arrival at each element. I would think so. However, I have not yet been able to make any measurements of either of the home-brew X-Y pairs that I have been working with to make a well-supported comment. |
#53
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John wrote: On 3/11/05 4:26 PM, in article 1110576331.158713@athnrd02, "Bob Pit" wrote: What are you looking for? As I said, I want to make hypnotic/subliminal mp3 files for myself. The only specs I have is "90 degree phase offset". I cannot describe it in other specific ways. I can send you a very small segment of a professional created mp3 file that use this technique if you want. If you are experienced, then you will know how they did it. I'll make some wildassed speculation here. Possible #1: Simple reverse-polarity between left and right channels. (while this is almost always thought of as "180deg phase shift". It's only 180deg at ONE frequency... Which is why everybody MUST understand that REVERSE PHASE really means NOTHING like REVERSE POLARITY). I don't know what "reverse phase" means, but reversing the polarity is EXACTLY THE SAME as a 180 degree phase shift at ALL frequencies; that is, Fourier transform the signal, shift all bands by 180 degrees and transform it back, and you have the opposite of the original signal. Of course the bands of any analog equalizer are far too coarse to ever see this effect. It can really only be done digitally. A 180 degree phase shift at only one frequency will result only result in reversed polarity at one frequency. If you doubt this, I'd be happy to supply the two lines of algebra to prove it. -jc This results (especially in headphones) in a bizarre sort of 'behind-me' effect. It also means that the sound COMPLETELY VANISHES when the audio is listened to in mono. What it might do to how various processors handle it, is up for grabs... For instance let's say you want to compress the stereo pair (which as I said are reverse=polarity) and the compressor senses the overall level at any instant by COMBINING left-and-right channels, just to derive the control signal to discern how much gain reduction to effect, then with the polarity flop in the signal, that control-signal instead of being a very real SUM of left and right overall levels, becomes ZERO and the compressor might do NOTHING or merely get 'interesting' in it's actions. POSSIBLE #2 Simple SHORT time-delay between channels. (on the order of milliseconds) This is actually phase-shift, but while the TIME might be a constant (say a few milliseconds) the amount of PHASE shifted varies with frequency, way more at hi's, very little with lo's. This again results (since it's playing with arrival-times at left-vs-right ear) in a 'where-IS-that-coming-from' effect in your head, again especially in headphones. When THIS sort of thing is summed to mono, the effect goes from a minimal vacuum-cleaner-hose hollow effect to, with time-delays on the order of 50ms on up, VERY whacked peaks and cancellations of frequencies all up and down the spectrum, mathematically related, that, when looked at on an analyser, show as regularly-spaced peaks and dips wider-and-fewer (for short delay times), through MASSIVE numbers of lines of peaks and dips closer and closer together at regular intervals, making the chart look like teeth in a comb. SUMMATION: These two are EASY to achieve with most any audio gear you have available. You might try them to see if they can do what you want to hear. You have nothing to lose (not even money!) Beyond these two approaches, you walk into the mathematical REAL world of serious weird stuff, and what the folks here have been going on (at wonderful length) about... And THAt has been a real breath of fresh air (excluding the kneejerk socially-inept inexcusable foulmouth overeactions to what SHOULD be simple pleasant exploration of a concept) amongst the mundanity. Hope this helps Jv |
#54
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Can you post a link to what you're talking about? It would be easier to offer help. Here is the link for a sample file that already has the effect: http://peter1861.atspace.com/index.html Bob |
#55
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Maybe I need to clarify.
I want to playback my voice (or any mp3 file) with a 90 degree phase offset between the 2 channels/speakers. (Or at least this is what they told me I have to do). How do you do this in CoolEdit pro? The reason I wan to do this is that it creates a very hypnotic effect. Here is a link to a file that has this effect: http://peter1861.atspace.com/index.html This is a binural file so you can only listen it with headphones. |
#56
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Bob Pit wrote:
Maybe I need to clarify. I want to playback my voice (or any mp3 file) with a 90 degree phase offset between the 2 channels/speakers. (Or at least this is what they told me I have to do). "They" were lying, or more likely "they" didn't have a clue what they were talking about. Here is a link to a file that has this effect: http://peter1861.atspace.com/index.html What you have there is the voice in the right channel is the left channel voice delayed by several tens of milliseconds. -- Anahata -+- http://www.treewind.co.uk Home: 01638 720444 Mob: 07976 263827 |
#57
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"Bob Pit" wrote in message
news:1110833493.656517@athnrd02... Maybe I need to clarify. I want to playback my voice (or any mp3 file) with a 90 degree phase offset between the 2 channels/speakers. (Or at least this is what they told me I have to do). How do you do this in CoolEdit pro? The reason I wan to do this is that it creates a very hypnotic effect. Here is a link to a file that has this effect: http://peter1861.atspace.com/index.html This is a binural file so you can only listen it with headphones. The voice track has been processed using some kind of convolution effect; then the right track is delayed about a 1/4 second. This does not appear to me to be simply an out of phase effect between two speakers. Steve King |
#58
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anahata wrote:
What you have there is the voice in the right channel is the left channel voice delayed by several tens of milliseconds. Further to that, I just tried loading it into audacity and found that if I delay the left channel by about 75msec the left and right voices are voices are synchronised. The original voice could well be mono, from the sound of it. There are other noises in the background, of course... A simple delay like that should be a standard CooEdit effect: it's a no-brainer in the digital domain. -- Anahata -+- http://www.treewind.co.uk Home: 01638 720444 Mob: 07976 263827 |
#59
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I made a recording of my voice. I put a 75 ms delay in one channel. Then I
went Effects - Time Pitch - Doppler Shifter - "Being Spun in Circles". I made the sound go full cirlce in 1 sec. I think I came pretty close to this effect. What do you think? Bob |
#60
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Well if the sound went around in a full circle, thats a 360 deg shift.
(in case you can't tell, the above message is tounge in cheek) :-) Mark |
#61
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"cirejcon" I don't know what "reverse phase" means, but reversing the polarity is EXACTLY THE SAME as a 180 degree phase shift at ALL frequencies; ** Completely stupid and wrong. Polarity reversal is an instantaneous process - ie there is no time delay. ............ Phil |
#62
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"Phil Allison" wrote in message ... ** Completely stupid and wrong. Polarity reversal is an instantaneous process - ie there is no time delay. There is no potential for gradual shifting? I seem to remember tools that do this. I seem to recall computer anomalies that do this. I seem to recall that it's easy to note when Phil hasn't taken his morning medication yet. DM |
#63
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"David Morgan (MAMS)" "Phil Allison" ** Completely stupid and wrong. Polarity reversal is an instantaneous process - ie there is no time delay. There is no potential for gradual shifting? ** DIE ,DIE, DIE - YOU ****ING CONTEXT SNIPPER !!!! This pig ignorant ASS does not even know what "polarity reversal" is. **** OFF ............... Phil |
#64
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"David Morgan (MAMS)" wrote in message news:Z7rZd.2521$Z07.394@trnddc02... "Phil Allison" wrote in message ... ** Completely stupid and wrong. Polarity reversal is an instantaneous process - ie there is no time delay. There is no potential for gradual shifting? Huh? Phil may be upside down there in au-land, but I gotta agree with him that there are no shades of polarity. Or has political correctness entered engineering also? :-) |
#65
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"Richard Crowley" "David Morgan (MAMS)" = anencephalic cretin "Phil Allison"... ** Completely stupid and wrong. Polarity reversal is an instantaneous process - ie there is no time delay. There is no potential for gradual shifting? Huh? Phil may be upside down there in au-land, but I gotta agree with him that there are no shades of polarity. ** A woman can be a bit positive or a bit negative - but not just a bit pregnant. Or has political correctness entered engineering also? :-) ** Not very likely - but a total incomprehension of *context* is at epidemic proportions among sound engineers. .................. Phil |
#66
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Mark wrote:
Well if the sound went around in a full circle, thats a 360 deg shift. (in case you can't tell, the above message is tounge in cheek) :-) Ok all joking aside, there are a lot of special effects available that screw up normal phase relationships in various ways; this is because we determine sound location largely by phase and frequency differences. Many Neve stereo line modules have width controls that can move stereo signals "outside" the normal stereo field, (the effect with stereo echoes can be that they come from *behind* you sometimes.) There are a lot of VST plug ins that do the same thing, expand the perceived stereo stage, and the "Circles" preset you allude to in the H3000 Harmonizer is supposed to simulate the effect of a source spinning around your head (you had to try to imagine it to hear it, I've always thought.) But although the stereo width VST plugins work pretty well, they usually require a stereo source. So if Bob Pit wants to screw up the phase on his vocals with those kinds of FX, he might try micing his vocals in stereo and then apply a plugin that does something with the stereo field. Or maybe an Eventide H3000 or something with similar FX presets. Will Miho NY Music & TV Audio Guy Staff Audio / Fox News / M-AES "The large print giveth and the small print taketh away..." Tom Waits |
#67
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On Mon, 14 Mar 2005 22:52:44 +0200, "Bob Pit" wrote:
Maybe I need to clarify. I want to playback my voice (or any mp3 file) with a 90 degree phase offset between the 2 channels/speakers. (Or at least this is what they told me I have to do). How do you do this in CoolEdit pro? The reason I wan to do this is that it creates a very hypnotic effect. Here is a link to a file that has this effect: http://peter1861.atspace.com/index.html This is a binural file so you can only listen it with headphones. AFAICS two processes have been applied. A delay of 0.1sec has been applied to the R channel. Both tracks have then been modulated by a 1Hz sine wave, giving a tremolo type volume envelope. The modulation on the R channel is about 0.3 sec ahead of the L channel. I assume the crackling and other distortion is just down to lousy quality. Maybe it's intentional :-) On headphones, does this give an effect of the voice moving around in and outside your head? CoolEdit used to feature a "brainwave generator" that made it easy to fool around with this sort of thing. But any competent wave editor will be able to do it. Just how this got described as a "90 degree phase offset" escapes me. But you've given a lot of people a lot of fun trying to take that requirement literally! Pity it wasn't what you needed :-) CubaseFAQ www.laurencepayne.co.uk/CubaseFAQ.htm "Possibly the world's least impressive web site": George Perfect |
#68
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Phil Allison wrote: "cirejcon" I don't know what "reverse phase" means, but reversing the polarity is EXACTLY THE SAME as a 180 degree phase shift at ALL frequencies; ** Completely stupid and wrong. Polarity reversal is an instantaneous process - ie there is no time delay. Look, come back after you've taken a basic math class and don't be rude if you don't have any idea what you're talking about. For anyone who actually understands algebra, sin(2*pi*f*t + phi + 180deg) = -sin(2*pi*f*t + phi) cos(2*pi*f*t + phi + 180deg) = -cos(2*pi*f*t + phi) I'd suggest you plug it in and check, but I doubt that your Little Tikes calculator can do trig. functions. -jc ........... Phil |
#69
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Laurence, thank you very much for the analysis.
A delay of 0.1sec has been applied to the R channel. We agree on this and I do know how to reproduce it in CoolEdit. Both tracks have then been modulated by a 1Hz sine wave, giving a tremolo type volume envelope. Can you please tell me how to do this in CoolEdit? The modulation on the R channel is about 0.3 sec ahead of the L channel. I am sorry, what do you mean? I thought the R channel was delayed. Can you please tell me how to do this in CoolEdit? I assume the crackling and other distortion is just down to lousy quality. Maybe it's intentional :-) No, it is intentional. It is supposed to be the noise coming from fire or something like this. On headphones, does this give an effect of the voice moving around in and outside your head? I sounds like the voise is moving from one side to another. It has a very hypnotic effect. Thanks Bob |
#70
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On Tue, 15 Mar 2005 20:57:57 +0200, "Bob Pit" wrote:
The modulation on the R channel is about 0.3 sec ahead of the L channel. I am sorry, what do you mean? I thought the R channel was delayed. Can you please tell me how to do this in CoolEdit? The R channel is indeed delayed. But the amplitude modulation applied to it is ahead of that applied to the L channel (dare I say "out of phase":-) I don't have CoolEdit, so I can't give detailed instructions how to achieve this. I'd be surprised if it wasn't achieved as a script in some program. Does anyone recognise it? CoolEdit did have a scripting feature, notably used for the "brainwaves" I mentioned previously. Does your version have preset scripts included? Any likely-sounding names there? I'd be looking for something called "Super-Spatial" or the like. CubaseFAQ www.laurencepayne.co.uk/CubaseFAQ.htm "Possibly the world's least impressive web site": George Perfect |
#71
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Laurence Payne wrote:
...snip.. The reason I wan to do this is that it creates a very hypnotic effect. Here is a link to a file that has this effect: http://peter1861.atspace.com/index.html This is a binural file so you can only listen it with headphones. AFAICS two processes have been applied. A delay of 0.1sec has been applied to the R channel. Both tracks have then been modulated by a 1Hz sine wave, giving a tremolo type volume envelope. The modulation on the R channel is about 0.3 sec ahead of the L channel. I noted a few more processed. In addition to the delay (my calculation came up with 99 ms) and amplitude modulation I also found several narrow EQ notches [ ~50Hz, ~100Hz, ~185 and ~205Hz plus a few more above 4kHz that I haven't looked at yet] and I believe the voice has been pitch shifted down about 2 semi-tones. The L&R EQ seem to be at slightly different frequencies, perhaps to add some differential group delay. I assume the crackling and other distortion is just down to lousy quality. Maybe it's intentional :-) ...snip.. I seem to hear crickets in the background and [IMHO] that crackling may be a poor simulation of a camp fire ...like maybe an outdoors ambiance. Anyway, that's my take on that clip. You're on your own with the cooledit. Later... Ron Capik -- |
#72
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"Richard Crowley" wrote in news:d15i87$ib5$1
@news01.intel.com: Huh? Phil may be upside down there in au-land, but I gotta agree with him that there are no shades of polarity. Or has political correctness entered engineering also? :-) DC polarity is an all-or-nothing thing, certainly. However, audio signals are, at best, fluctuating DC or (more likely) AC, and when you are comparing *two* (or more) signals, or copies of the same signal, there may indeed be a "partial polarity change" - a phase shift. This may be induced in many ways, the simplest being a delay line in one channel. A 180 degree phase shift would be the "all-or-nothing" flip; any other phase shift is going to be that partial polarity change which someone insists just can't happen. -- Email, Smarthosting, Web hosting for individuals and business: Come to http://www.spamblocked.com "I ran the Malicious Software Removal Tool, and now all my MS ware is gone!" |
#73
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"The Open Sourceror's Apprentice" wrote in message 11.247... "Richard Crowley" wrote in news:d15i87$ib5$1 @news01.intel.com: Huh? Phil may be upside down there in au-land, but I gotta agree with him that there are no shades of polarity. Or has political correctness entered engineering also? :-) DC polarity is an all-or-nothing thing, certainly. However, audio signals are, at best, fluctuating DC or (more likely) AC, and when you are comparing *two* (or more) signals, or copies of the same signal, there may indeed be a "partial polarity change" - a phase shift. This may be induced in many ways, the simplest being a delay line in one channel. A 180 degree phase shift would be the "all-or-nothing" flip; any other phase shift is going to be that partial polarity change which someone insists just can't happen. And THAT is the difference between *polarity* and *phase*. Degrees of phase: clearly. Degrees of polarity: two. |
#74
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OK, I made this file "bob-test - delay 100 ms - 1 Hz.mp3" located at
http://peter1861.atspace.com/index.html . According to your analysis, a delay of 0.1sec has been applied to the R channel. Both tracks have then been modulated by a1Hz sine wave. That's all. As for the "The modulation on the R channel is about 0.3 sec ahead of the L channel", I cannpt figure how to do it (if it is not already there). Bob |
#75
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"Richard Crowley" wrote in message ... "The Open Sourceror's Apprentice" wrote in message 11.247... "Richard Crowley" wrote in news:d15i87$ib5$1 @news01.intel.com: Huh? Phil may be upside down there in au-land, but I gotta agree with him that there are no shades of polarity. Or has political correctness entered engineering also? :-) DC polarity is an all-or-nothing thing, certainly. However, audio signals are, at best, fluctuating DC or (more likely) AC, and when you are comparing *two* (or more) signals, or copies of the same signal, there may indeed be a "partial polarity change" - a phase shift. This may be induced in many ways, the simplest being a delay line in one channel. A 180 degree phase shift would be the "all-or-nothing" flip; any other phase shift is going to be that partial polarity change which someone insists just can't happen. And THAT is the difference between *polarity* and *phase*. Degrees of phase: clearly. Degrees of polarity: two. OK then... is this where I'm supposed to type a half dozen double-spaced asterisks followed by a flaming, "This is WRONG you a**hole dimwit... read the header..."? or maybe start a change of header calling Phil something wretchedly assanine and make it clear that the OP used the word "phase"? ;-) DM |
#76
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On Wed, 16 Mar 2005 00:04:33 +0200, "Bob Pit" wrote:
As for the "The modulation on the R channel is about 0.3 sec ahead of the L channel", I cannpt figure how to do it (if it is not already there). If your wave editor has no control over the phase of a LFO signal, you could do this. Split R and L channel as completely separate files. Trim 0.3sec off the front of one file. Apply the modulation to each. Now trim 0.3 sec off the other file and recombine them as stereo. Later, having tried it out: Amazingly, none of the wave editors I have here seem to have a simple LFO function. Audition could probably do it with Convolution. There's certainly a function to create a 1Hz sine wave, with control over the initial phase. CubaseFAQ www.laurencepayne.co.uk/CubaseFAQ.htm "Possibly the world's least impressive web site": George Perfect |
#77
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"Bob Pit" writes:
Hi I am not very familiar with CoolEdit and I want to playback my voice (or any mp3 file) with a 90 degree phase offset between the 2 channels/speakers. It must be easy but how do you do this? Thanks Bob Hi Bob, I don't know about CoolEdit, but in Adobe Audition you simply select /Effects/Filters/Graphic Phase Shifter... . That brings up a dialog with various presets available, two of which are +90 and -90. I found an audible difference on a section of Crosby, Stills, Nash, and Young's old "Our House": www.uspsdata.org/OurHouse90.wav -- % Randy Yates % "Rollin' and riding and slippin' and %% Fuquay-Varina, NC % sliding, it's magic." %%% 919-577-9882 % %%%% % 'Living' Thing', *A New World Record*, ELO http://home.earthlink.net/~yatescr |
#78
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Randy Yates writes:
[...] I found an audible difference on a section of Crosby, Stills, Nash, and Young's old "Our House": www.uspsdata.org/OurHouse90.wav I should have mentioned that the clip starts out phase shifted (between L and R) and then reverts to no phase shift about half way through. -- % Randy Yates % "I met someone who looks alot like you, %% Fuquay-Varina, NC % she does the things you do, %%% 919-577-9882 % but she is an IBM." %%%% % 'Yours Truly, 2095', *Time*, ELO http://home.earthlink.net/~yatescr |
#79
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YES.
I've always heard that too, especially when listening in mono. To me its the worst (best) example of a technical issue on a well known recording. If I recall, I think I heard that the different sections were actually recorded at diffrent studios. Mark |
#80
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"cirejcon" Phil Allison I don't know what "reverse phase" means, but reversing the polarity is EXACTLY THE SAME as a 180 degree phase shift at ALL frequencies; ** Completely stupid and wrong. Polarity reversal is an instantaneous process - ie there is no time delay. Look, come back after you've taken a basic math class and don't be rude if you don't have any idea what you're talking about. ** To have utterly failed to comprehend the issue - dickhead !!!!! Phase shifting involves time delay between the original and the shifted versions. Polarity reversal does not. A transformer with a secondary centre tap connected to ground will produce *simultaneous* signals which are identical in magnitude at any instant but of opposite polarity. ........... Phil |
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