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[email protected] nigel@telepathy.co.uk is offline
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Default 4Ohm Speakers 8 Ohm Amp

OK may be a dumb question, but could you use resistors to up the
resistance of 4 Ohm speakers so they could be driven by a 8Ohm amp???

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Trevor Wilson Trevor Wilson is offline
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Default 4Ohm Speakers 8 Ohm Amp


wrote in message
ups.com...
OK may be a dumb question, but could you use resistors to up the
resistance of 4 Ohm speakers so they could be driven by a 8Ohm amp???


**Sure. Make certain your resistors are rated for half the power of the
amplifier though (they may get very hot). Damping factor will go out the
window and you'll throw away 50% of the amplifier power, but it will work.

Personally, I don't see any value in buying *any* amplifier which cannot
drive at least 4 Ohm loads.


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Trevor Wilson
www.rageaudio.com.au



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Trevor Wilson Trevor Wilson is offline
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Default 4Ohm Speakers 8 Ohm Amp


"Bret Ludwig" wrote in message
ups.com...

Trevor Wilson wrote:
wrote in message
ups.com...
OK may be a dumb question, but could you use resistors to up the
resistance of 4 Ohm speakers so they could be driven by a 8Ohm amp???


**Sure. Make certain your resistors are rated for half the power of the
amplifier though (they may get very hot). Damping factor will go out the
window and you'll throw away 50% of the amplifier power, but it will
work.

Personally, I don't see any value in buying *any* amplifier which cannot
drive at least 4 Ohm loads.


An autoformer would work much better.


**Oh, please! Adding an autoformer to a solid state amp, is like sticking a
fifth wheel to a Porsche. It is MUCH cheaper and far more effective to
increase the SOA (more output devices and heat sinking) of the output stage,
than adding kilos of iron and copper. Autoformers (in 2006) are a waste of
time money and mass. Transistors and aluminium (or fans) are cheap,
effective and light weight.


--
Trevor Wilson
www.rageaudio.com.au



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[email protected] rcfindlay@gmail.com is offline
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Default 4Ohm Speakers 8 Ohm Amp


Trevor Wilson wrote:
"Bret Ludwig" wrote in message
ups.com...

Trevor Wilson wrote:
wrote in message
ups.com...
OK may be a dumb question, but could you use resistors to up the
resistance of 4 Ohm speakers so they could be driven by a 8Ohm amp???

**Sure. Make certain your resistors are rated for half the power of the
amplifier though (they may get very hot). Damping factor will go out the
window and you'll throw away 50% of the amplifier power, but it will
work.

Personally, I don't see any value in buying *any* amplifier which cannot
drive at least 4 Ohm loads.


An autoformer would work much better.


**Oh, please! Adding an autoformer to a solid state amp, is like sticking a
fifth wheel to a Porsche. It is MUCH cheaper and far more effective to
increase the SOA (more output devices and heat sinking) of the output stage,
than adding kilos of iron and copper. Autoformers (in 2006) are a waste of
time money and mass. Transistors and aluminium (or fans) are cheap,
effective and light weight.



Tragic they sound so bad....McIntosh solid state amps are the best
sounding solid state amps, but not as good as tube amps. Especially
triodes.

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dizzy dizzy is offline
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Default 4Ohm Speakers 8 Ohm Amp

Trevor Wilson wrote:

wrote:

OK may be a dumb question, but could you use resistors to up the
resistance of 4 Ohm speakers so they could be driven by a 8Ohm amp???


**Sure. Make certain your resistors are rated for half the power of the
amplifier though (they may get very hot). Damping factor will go out the
window and you'll throw away 50% of the amplifier power, but it will work.


Eh? As I understand it, that would cause significant frequency
response errors, as the varying impedance of the speaker consumes
varying amounts of the output voltage, due to the series resistor.

Personally, I don't see any value in buying *any* amplifier which cannot
drive at least 4 Ohm loads.


Find a modern surround receiver that's rated for 4 ohms. Uncommon, to
say the least.



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dizzy dizzy is offline
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Default 4Ohm Speakers 8 Ohm Amp

wrote:

McIntosh solid state amps are the best
sounding solid state amps, but not as good as tube amps. Especially
triodes.


In your (whacked) opinion...

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Trevor Wilson Trevor Wilson is offline
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Default 4Ohm Speakers 8 Ohm Amp


wrote in message
ups.com...

Trevor Wilson wrote:
"Bret Ludwig" wrote in message
ups.com...

Trevor Wilson wrote:
wrote in message
ups.com...
OK may be a dumb question, but could you use resistors to up the
resistance of 4 Ohm speakers so they could be driven by a 8Ohm
amp???

**Sure. Make certain your resistors are rated for half the power of
the
amplifier though (they may get very hot). Damping factor will go out
the
window and you'll throw away 50% of the amplifier power, but it will
work.

Personally, I don't see any value in buying *any* amplifier which
cannot
drive at least 4 Ohm loads.


An autoformer would work much better.


**Oh, please! Adding an autoformer to a solid state amp, is like sticking
a
fifth wheel to a Porsche. It is MUCH cheaper and far more effective to
increase the SOA (more output devices and heat sinking) of the output
stage,
than adding kilos of iron and copper. Autoformers (in 2006) are a waste
of
time money and mass. Transistors and aluminium (or fans) are cheap,
effective and light weight.



Tragic they sound so bad.


**Dream on. In a properly configured blind test, YOU can hear no problems
with a decently designed amp, which does not use autoformers.

....McIntosh solid state amps are the best
sounding solid state amps,


**Nope. Not even close. However, I'll bite. Explain, in as much detail as
you see fit, why you think the addition of an extra, unneeded component, to
an otherwise regular amplifier can improve sound quality. I look foreward to
your considered explanation.

but not as good as tube amps. Especially
triodes.


**More bull****. Triode amps and Pentode amps are fundamentally different.
However, the very best tube amps sound almost indistinguishable from
excellent solid state amps, when driving appropriate loads. I know. I've
actually taken part in blind tests, where I was unable to reliably identify
a really excellent tube amp and a really excellent solid state amp. Have
you?

Having said that, the current fashion for SET amps, is just that - a fashion
statement. SET amps have no redeeming qualities in high fidelity
applications.


--
Trevor Wilson
www.rageaudio.com.au



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Trevor Wilson Trevor Wilson is offline
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Default 4Ohm Speakers 8 Ohm Amp


"dizzy" wrote in message
...
Trevor Wilson wrote:

wrote:

OK may be a dumb question, but could you use resistors to up the
resistance of 4 Ohm speakers so they could be driven by a 8Ohm amp???


**Sure. Make certain your resistors are rated for half the power of the
amplifier though (they may get very hot). Damping factor will go out the
window and you'll throw away 50% of the amplifier power, but it will work.


Eh? As I understand it, that would cause significant frequency
response errors, as the varying impedance of the speaker consumes
varying amounts of the output voltage, due to the series resistor.


**I did say that damping factor will go out the window. Frequency repsonse
abberrations are an artefact of this. Naturally, with speakers like
Magneplannars, such problems are almost insignificant.


Personally, I don't see any value in buying *any* amplifier which cannot
drive at least 4 Ohm loads.


Find a modern surround receiver that's rated for 4 ohms. Uncommon, to
say the least.


**See above. My comments remain. I deal in high fidelity, not also-ran
fidelity.


--
Trevor Wilson
www.rageaudio.com.au



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Arny Krueger Arny Krueger is offline
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Default 4Ohm Speakers 8 Ohm Amp

wrote in message
ups.com

OK may be a dumb question, but could you use resistors to
up the resistance of 4 Ohm speakers so they could be
driven by a 8Ohm amp???


Sure you could, and this was done in some commercial amps in the early days
of solid state. I had such an amp - a Heath AA-22. One day I decided to
drive a pair of AR3s (4 ohms) on the 8 ohm taps. It was a low-powered amp
and easy to overdrive. The next day I ordered up a new set of output
transistors. Early SS amps didn't have appropriate protection built-in.

These days, good amps always have appropriate protection built-in. Not only
can good modern amps rated at 8 ohms drive 4 ohm speakers without failing,
they can drive 0-ohm shorted speaker leads without failing.

Most amps that are rated at 8 ohms are rated at 8 ohms so that they can
survive continuous-since wave signal testing on the bench. In practical use
the mostly likely problem would be overheating, but that is improbable
unless you are pushing the @!$##!! out of them.

If you're a DJ or a hard rock band, then don't use your power amp to drive
speakers with too low of a rated impedance. If you are a typical audiophile,
don't sweat the small stuff.



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dizzy dizzy is offline
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Default 4Ohm Speakers 8 Ohm Amp

Trevor Wilson wrote:

Personally, I don't see any value in buying *any* amplifier which cannot
drive at least 4 Ohm loads.


Find a modern surround receiver that's rated for 4 ohms. Uncommon, to
say the least.


**See above. My comments remain. I deal in high fidelity, not also-ran
fidelity.


I hear 'ya, and agree. I was sideways commenting on the sad state of
reality, from the perspective of the more casual A/V enthusiast, for
whom the surround-sound receiver, due it's sales volumes, offers
tremendous value.

Those of us who aren't happy with the mass-market stuff sure pay a
premium, don't we? 8)



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Default 4Ohm Speakers 8 Ohm Amp

Trevor Wilson wrote:

**Sure. Make certain your resistors are rated for half the power of the
amplifier though (they may get very hot). Damping factor will go out the
window and you'll throw away 50% of the amplifier power, but it will work.


Eh? As I understand it, that would cause significant frequency
response errors, as the varying impedance of the speaker consumes
varying amounts of the output voltage, due to the series resistor.


**I did say that damping factor will go out the window. Frequency repsonse
abberrations are an artefact of this.


I think you downplayed the negative consequences, though. IMO, adding
the series 4-ohm resistor is really not an acceptable solution.

Naturally, with speakers like
Magneplannars, such problems are almost insignificant.


Does the OP have Maggies?

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Default 4Ohm Speakers 8 Ohm Amp

Arny Krueger wrote:

These days, good amps always have appropriate protection built-in. Not only
can good modern amps rated at 8 ohms drive 4 ohm speakers without failing,
they can drive 0-ohm shorted speaker leads without failing.

Most amps that are rated at 8 ohms are rated at 8 ohms so that they can
survive continuous-since wave signal testing on the bench. In practical use
the mostly likely problem would be overheating, but that is improbable
unless you are pushing the @!$##!! out of them.


My surround-sound receiver (used only for movies, but sharing, via
cable-swap, my main, 4-ohm, music-system speakers) is a Pioneer Elite
rated down to 6 ohms. It usually works fine, but intense soundtracks
have caused it to self-protect.

It helps that I have my surround setup as "main speakers are small"
(even though they're not 8), so my poor Pioneer doesn't have to do
the low notes. I also raised the X-over freq to 100 Hz, instead of
the 80Hz default.

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