Is THD is the lodestar? or maybe distortion is akin to probiotics, as long as it’s the right kind it’s very healthy
If we accept different people like different things then the debate goes away.
Now there's an idea.
And, no. The THD is not the be-all, end-all. It just happens to be measured for just about every amp which makes it easy to compare one amp versus the other. I would argue that IMD, in particular multi-tone IMD, is vastly more important because it's more obtrusive. But that requires that people can read a fairly complex graph rather than just comparing two numbers.
Tom
And, no. The THD is not the be-all, end-all. It just happens to be measured for just about every amp which makes it easy to compare one amp versus the other. I would argue that IMD, in particular multi-tone IMD, is vastly more important because it's more obtrusive. But that requires that people can read a fairly complex graph rather than just comparing two numbers.
Tom
OP, all amplifier is sound the same ,, all you have to do is to pick a best speaker you can afford to match the amplifier
H
HAYK
Traditionally amplifier designers try to minimize non-linear distortion (usually harmonic distortion, sometimes two-tone intermodulation or multitone intermodulation distortion) without caring much about frequency response and loudspeaker designers try to optimize frequency response without caring much about non-linear distortion.
lol... yep. pretty much
just like probiotics where anything soaked in acid and buttermilk and cheese is supposedly good for you.
well class AB it is lol
just like probiotics where anything soaked in acid and buttermilk and cheese is supposedly good for you.
well class AB it is lol
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D
Deleted member 550749
THIS LM3886 INTERNAL SCHEMATIC, copied from datasheet, and simplified, tested and cirquit is working, offset 0.1mv/1uma, output transistor under 80ma quiscent current, and output rms at 16volt/4ohm load sounds , love the frequency response itcan play lower 6hz that's amazed me ☺️
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Isn't HD and IMD in reality completely related - i.e. one cant have a low THD amp with high IMD avv.
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A mixer, by definition, generates IMD. I think it's possible to have a mixer with low HD. Similarly for AM and FM/PM modulators.
Tom
Tom
I gather you mean a mixer in the RF sense, not an audio mixing console (+), and that you refer to what happens when the RF and LO signals together produce the IF signal (or IF and LO produce RF, in a transmitter with up mixer). You can indeed regard that as a kind of intermodulation distortion if you like. You can also regard the mixer and the LO generation circuitry together as an approximately linear, but time-variant system, whatever you find convenient.
Usually when RF designers talk about the intermodulation distortion of a mixer, they mean intermodulation between different frequency components of the RF (or IF) signal. That intermodulation distortion can be quite low if it is a good mixer.
(+): Although when you turn a knob or shift a fader of a mixing console, you get the same type of intermodulation between the audio signal and the mechanical signal that turns the knob or shifts the fader.
Usually when RF designers talk about the intermodulation distortion of a mixer, they mean intermodulation between different frequency components of the RF (or IF) signal. That intermodulation distortion can be quite low if it is a good mixer.
(+): Although when you turn a knob or shift a fader of a mixing console, you get the same type of intermodulation between the audio signal and the mechanical signal that turns the knob or shifts the fader.
For a smoothly non-linear instantaneous system, you can calculate one from the other, but because of the loop gain that varies a lot over the audio band, it can be more complicated for an audio amplifier. Still, usually, high harmonic distortion means high intermodulation distortion and the other way around.
Correct. I suppose in the analog world it would be considered a multiplier.
Which is one of the reasons I optimize for low harmonic distortion. It's not that the harmonic distortion alone is a be-all, end-all but in order to get ultra-low levels of distortion you need to improve the circuit in many ways. Those improvements - and the improvements in IMD are worth having.
But I get it. Some want their audio system to add a little something-something to the sound. That's fine. I just happen not to be one of them.
Tom
I second that. I have had a chance to listen to this amplifier where there is ability to adjust negative feedback. It sounded the best with zero negative feedback applied. Amps THD ratings were <0.1% with no NFB by the way.
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Much of the rest of a system has been adjusted to class A/B etc distorsion to create a nice sum - i.e. the sound that we hear from our systems. Enters Class-D with lower distortion and breaks the "system" balance.... An improvement that became for many a disappointment due to the rest of their system.... it's a system game ....
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What about the extra power that class d seems to offer, niali and purifi have silly numbers vs say 40-65w chip amps. Is the headroom needed if I'm in a small listening room. I hear a lot aboit the first watti.
I agree that the resulting sound is about the whole system - the synergy of individual components.
I was stuck with class AB amplifiers for a long while, then moved to valves and really liked the 6C33C single-ended amp I got from a friend of mine (from Poland).... then I started with class A (push-pull)... and finally arrived at single-ended class A.
The single-ended class A amplifier forced me to do something that no other amps have done for me - update the source (DAC).
The DAC & amp synergy then forced me to seriously look at the streamer and in particular... the power supply. I spent a lot of time playing with the power supplies for my streamer with unbelievable results...
I was stuck with class AB amplifiers for a long while, then moved to valves and really liked the 6C33C single-ended amp I got from a friend of mine (from Poland).... then I started with class A (push-pull)... and finally arrived at single-ended class A.
The single-ended class A amplifier forced me to do something that no other amps have done for me - update the source (DAC).
The DAC & amp synergy then forced me to seriously look at the streamer and in particular... the power supply. I spent a lot of time playing with the power supplies for my streamer with unbelievable results...
In class D amplification there is the DIY Hypex Nilai500 and the others. It is the only class D I would use to power the tweeter, for quality recordings with physical instruments and vocals without autotune.
Electronic music and others, Purifi is OK or maybe better.