It is a fallacy that an asymmetric waveform always produces a partial dc offset - what ever the partial means in that context.
Yes, that's true, I was considering the signal as being a random (or at least uncorrelated) set of values as opposed to a purposely constructed set of values. We are close to the straight line that continues to infinity or at least the end of the black board...
Of course some circuits are designed to react differently to symmetric and asymmetric signals
May not be by design, but they are also often called "single ended" amplifiers.
Whenever an honest man discovers that he's mistaken, he will either cease to be mistaken or he will cease to be honest.
I suppose generically we would call them effects boxes
Not that I agree that all single ended amplifiers treat symmetric and asymmetric signals differently but certainly some ( alright - a lot) do...
On the other hand PP amplifiers are inherently inaccurate in that they don't treat even and odd harmonics in the signal the same... again not 100% accurate but certainly mostly true...
perhaps I should add that these harmonics are present in every music signal i.e. anything other than a single frequency sine (or cosine) wave...
On the other hand PP amplifiers are inherently inaccurate in that they don't treat even and odd harmonics in the signal the same... again not 100% accurate but certainly mostly true...
Actually, I think as written that's a variation of Steve's original question, and I would say entirely false. The distortion products they produce has differences between odd and even, but I would question if they in any sense are aware of harmonics in the original signal.
Whenever an honest man discovers that he's mistaken, he will either cease to be mistaken or he will cease to be honest.
I've measured PP amps reducing the even harmonics of a mudic signal by comparing FFTs of a single note produced by an oboe... I tried six different amps and the 5 PP amps all reduced the second and fourth harmonic whilst the se amp increased them
The tube manual is quite like a telephone book. The number of it perfect. It is useful to make it possible to speak with a girl. But we can't see her beautiful face from the telephone number
JamesD wrote: ↑Mon May 23, 2022 1:43 pm
I've measured PP amps reducing the even harmonics of a mudic signal by comparing FFTs of a single note produced by an oboe... I tried six different amps and the 5 PP amps all reduced the second and fourth harmonic whilst the se amp increased them
And i bet many speakers wouldn't even reproduce those harmonics
The tube manual is quite like a telephone book. The number of it perfect. It is useful to make it possible to speak with a girl. But we can't see her beautiful face from the telephone number
One of the reasons I posted is that I'd read that it is the harmonics that add to the asymmetrical aspects of music
I'd linked a minor lack of harmonics to most push pull amplifiers that I've heard. And perceived there may be a link somewhere..
The tube manual is quite like a telephone book. The number of it perfect. It is useful to make it possible to speak with a girl. But we can't see her beautiful face from the telephone number
JamesD wrote: ↑Mon May 23, 2022 1:43 pm
I've measured PP amps reducing the even harmonics of a mudic signal by comparing FFTs of a single note produced by an oboe... I tried six different amps and the 5 PP amps all reduced the second and fourth harmonic whilst the se amp increased them
Yes, I would expect that. You are taking a signal that is mostly a sine wave with some harmonics, passing that through an amplifier that generates a set of distortion harmonics from that signal where the odd ones will dominate. You then add those new harmonics to the original signal and the result will means that the even harmonics will remain as before or cancel which even harmonics can do when added and the odd ones will sum and increase, so you would expect a larger level of odd harmonics in the result. I know it is a process of multiplication instead of addition, but the bulk of the generated harmonics will be from the fundamental so will align with the original signal harmonics.
But I would say that's not a case of the amplifier treating the harmonics differently it just looks as though its treating them differently as the result is the same as if it was doing that.
That may be a trivial difference, but I think if you don't make that distinction it could lead you down a rabbit hole where you start to expect non trivial results, or justify results that don't actually happen.
Whenever an honest man discovers that he's mistaken, he will either cease to be mistaken or he will cease to be honest.
JamesD wrote: ↑Mon May 23, 2022 1:43 pm
whilst the se amp increased them
Is that at one with nature...
In that harmonics increase with volume
The tube manual is quite like a telephone book. The number of it perfect. It is useful to make it possible to speak with a girl. But we can't see her beautiful face from the telephone number
I'd linked a minor lack of harmonics to most push pull amplifiers that I've heard. And perceived there may be a link somewhere..
And I used that line of thought to justify the attempt to make an amplifier that does as little as possible (or as little as I could make it do) to the signal. You may be in danger of using it to go down one of those rabbit holes I mentioned in my last post.
Whenever an honest man discovers that he's mistaken, he will either cease to be mistaken or he will cease to be honest.
JamesD wrote: ↑Mon May 23, 2022 1:43 pm
whilst the se amp increased them
Is that at one with nature...
In that harmonics increase with volume
Do they? Does the harmonic content of a trumpet in a field change as you get closer to it?
I would say the trumpet stays the same but as you get closer they become more audible.?
The tube manual is quite like a telephone book. The number of it perfect. It is useful to make it possible to speak with a girl. But we can't see her beautiful face from the telephone number
