N is the highest order of distortion per stage. In real life N is always infinity, but for a well-behaved stage you can use N as the highest order of significant distortion. In that case N may be 2 or 3. Cancellation then gives distortion up to 4th, 5th or 6th order. Of course, this order-multiplication still occurs with any stage cascades but cancellation (usually of second order) can lead people to run with more distortion in each stage and assume cancellation will take care of it.
This thread amuses me greatly.
The OP asked why a very old technology produces such distorted sound and we get an exercise in dis****ed thinking. Please correct me if I am wrong, but distortion represents a difference between the input and output signals, that is, the greater the distortion, the greater the difference between what was recorded and what a listener hears?
How is this good?
The OP asked why a very old technology produces such distorted sound and we get an exercise in dis****ed thinking. Please correct me if I am wrong, but distortion represents a difference between the input and output signals, that is, the greater the distortion, the greater the difference between what was recorded and what a listener hears?
How is this good?
I have close to zero proper experience of SE, except for a 3in1 tube amp chassis that was then eons old, and that was eons ago.
I have not followed the discussion fully here...yet.
As I understand it, SE means asymmetrical waveform output, for a clean sine input.
IOW, there is a directional (polarity) characteristic to the output waveform.
IME, simple (as opposed to many multi, close mic'd sources/channels) recording techniques yield a directional (polarity conscious) waveform....this is referred to as depth information.
So, what is listeners experience of flipping source signal polarity and/or loudspeaker polarity ???.
I expect SE amplifier non linear behavior to cause exaggeration, or diminution of peaks, and skewing/alteration of depth information, when combined with the non linear polarity conscious alterations in loudspeakers.
So, what is listeners experience of flipping signal source polarity and/or speaker polarity when using SE preamplifiers and/or SE amplifiers ???.
Dan.
I have not followed the discussion fully here...yet.
As I understand it, SE means asymmetrical waveform output, for a clean sine input.
IOW, there is a directional (polarity) characteristic to the output waveform.
IME, simple (as opposed to many multi, close mic'd sources/channels) recording techniques yield a directional (polarity conscious) waveform....this is referred to as depth information.
So, what is listeners experience of flipping source signal polarity and/or loudspeaker polarity ???.
I expect SE amplifier non linear behavior to cause exaggeration, or diminution of peaks, and skewing/alteration of depth information, when combined with the non linear polarity conscious alterations in loudspeakers.
So, what is listeners experience of flipping signal source polarity and/or speaker polarity when using SE preamplifiers and/or SE amplifiers ???.
Dan.
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Some listeners can detect absolute phase on some music. Nothing whatsoever to do with 'depth'. I don't think absolute phase is the secret of SE, as SE does not preserve/invert it any more/less than PP.
SE is favoured by those who prefer simplicity and/or prefer a little second-order 'warmth'. Some try to avoid this by arranging (or believing that they have arranged) some distortion cancellation between the first and second stages. The result is more high order distortion. There is an alternative way to do distortion cancellation which does not create extra high order terms: it is known as push-pull.
SE is favoured by those who prefer simplicity and/or prefer a little second-order 'warmth'. Some try to avoid this by arranging (or believing that they have arranged) some distortion cancellation between the first and second stages. The result is more high order distortion. There is an alternative way to do distortion cancellation which does not create extra high order terms: it is known as push-pull.
It's not really a preference for added second order warmth, rather it's the lesser of two evils.
Sure but PP has it's own set of problems, if you are anal about SE, I don't see what's to like about PP.
"Warmth" and harmonics aside, SE just has more coherency, or at least sounds that way.
Crossover distortion in PP amps and the lack of it in SE amps, make SE sound slightly better by comparison.
DF96 care to elaborate on some listeners being able to detect absolute phase on some music?
In order to have "phase" assumes you have a timeline and polarity to compare it to.
This timeline starts whenever the music starts.
I'm sorry but that statement is a tad ridiculous.
The human hear is counting the peaks and amplitudes, it would not matter whether the first voltage swing goes down instead of up etc.
A sine wave is just that, it only has a negative swing if you apply that name to half of it. Flip your scope upside down and.....
Phase is obviously important if you are trying to synchronize something etc, it is not an issue coming from a singular source.
If you consider the phase moving from left to right it helps to visualize the insignificance of whether the first impulse in a series of vibrations moves left or right.
I'm sure someones head is about to implode right now.
Sure but PP has it's own set of problems, if you are anal about SE, I don't see what's to like about PP.
"Warmth" and harmonics aside, SE just has more coherency, or at least sounds that way.
Crossover distortion in PP amps and the lack of it in SE amps, make SE sound slightly better by comparison.
DF96 care to elaborate on some listeners being able to detect absolute phase on some music?
In order to have "phase" assumes you have a timeline and polarity to compare it to.
This timeline starts whenever the music starts.
I'm sorry but that statement is a tad ridiculous.
The human hear is counting the peaks and amplitudes, it would not matter whether the first voltage swing goes down instead of up etc.
A sine wave is just that, it only has a negative swing if you apply that name to half of it. Flip your scope upside down and.....
Phase is obviously important if you are trying to synchronize something etc, it is not an issue coming from a singular source.
If you consider the phase moving from left to right it helps to visualize the insignificance of whether the first impulse in a series of vibrations moves left or right.
I'm sure someones head is about to implode right now.
I understand that proper tests have demonstrated that some (a minority) of people can detect absolute phase on some (certain instruments only) music. A corollary of this is that most people cannot detect absolute phase on any music, and even the minority can't do it for all music. This may seem ridiculous, but I understand it to be true.H E Pennypacker said:
Music waveforms are often asymmetrical, because they include even harmonics. That is a fact. An alternative way of looking at it is to remember that one someone hits a drum the initial effect is a reduction in air pressure. How some people can detect the phase is for others to answer.
These are absolutely none issues in a PP amp designed to run in Class A. A PP amp can be built as two back to back SE amps and will deliver all of the benefits of SE along with the benefits of PP. In short it can give more than an SE amp.
Your statements are based upon a false perception of what a PP amp has to be.
Shoog
Not at all.
Crossover distortion is greatly reduced with class A PP, but it's still there.
You may experience it as odd order harmonics at high power levels.
It may not be worth the practical effort it would take to make crossover distortion practically disappear in a class A PP.
That is why I say SE has a natural coherency advantage over PP, it's just one problem that does not exist with class A SE.
The Correct Term Is Absolute Polarity, NOT Absolute Phase...
Music is not all sinewaves.
Get an assistant to shoot a gun directly away from you, or directly over the top of your head.
These are two very different sounds.
Absolute polarity is readily discernible on single driver systems....crossover phase rotations typically confuse the perceived polarity, hence subjective confusion.
Sheesh.
Dan.
Relative phase is NOT the same as signal/acoustic polarity.
Music is not all sinewaves.
Get an assistant to shoot a gun directly away from you, or directly over the top of your head.
These are two very different sounds.
Absolute polarity is readily discernible on single driver systems....crossover phase rotations typically confuse the perceived polarity, hence subjective confusion.
Sheesh.
Dan.
Obviously music is not pure sine waves, they are complex erratic transient waves, but still waves.
The electrical information correlates exactly (ideal world) with the acoustical pressure waves originally recorded. Ideally a reproduction system just does this in reverse.
"Get an assistant to shoot a gun directly away from you, or directly over the top of your head.
These are two very different sounds."
Of course they are, but this logic is flawed.
If I recorded both of those sounds then played them back once in phase, then once out of phase, they would still sound identical.
In fact I can play it in phase, reverse the polarity on a full range driver so it is out of phase, it would still sound the same.
It's the reason why single driver guitar amps don't have a "polarity" for the speaker, practically speaking.
The electrical information correlates exactly (ideal world) with the acoustical pressure waves originally recorded. Ideally a reproduction system just does this in reverse.
"Get an assistant to shoot a gun directly away from you, or directly over the top of your head.
These are two very different sounds."
Of course they are, but this logic is flawed.
If I recorded both of those sounds then played them back once in phase, then once out of phase, they would still sound identical.
In fact I can play it in phase, reverse the polarity on a full range driver so it is out of phase, it would still sound the same.
It's the reason why single driver guitar amps don't have a "polarity" for the speaker, practically speaking.
Crossover distortion is by definition the waveform glitch as one valve switches off. In class A that never happens. By definition crossover distortion is absent. There maybe other forms of distortion - but not crossover.
Shoog
Transient sounds are pulses with an AC decay characteristic....AC component, but net DC energy transfer.
Yes.
Please explain.
No way.
Some do, and it makes a very obvious sonic difference.
Dan.
Crossover distortion that is heard is due to nonlinearities in the OPTs and the timing of the two halves due to having a phase splitter.
Distortion canceling abilities are also slightly over-rated as they only cancel out in the power stage, take it as you will.
Distortion canceling abilities are also slightly over-rated as they only cancel out in the power stage, take it as you will.
No it doesn't.
The phase of a single driver guitar amplifier is determined by the phase of the pickups/strings which in turn are initiated by when the musician strikes the string.
Every time he plays that song, the strings will be out of phase with the previous time he played it.
This is simply redefining a generally understood term. Solid state amps have crossover distortion and it is produced when one transistor goes into switch off and it manifests as a spike or dip at the switch off point.
Mismatch of the transfer characteristics of the output device is another type of distortion and is largely treated by signal merging within the output transformer - which is the distortion cancellation you refer to. It results in 3rd and higher harmonics and as such is a form of harmonic distortion.
Shoog
It does sound like a fun amplifier though.
What is a good example of a popular class A PP that people are building?
What is a good example of a popular class A PP that people are building?
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