Influence of the delay amplifiers for listening characteristics

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the only way phase create distorsion is phase modulation, a signal
modulating another and changing his frequency..
this has been extensively used in FM synthesizers, like the famed DX7, although
it was not frequency modulation but phase modulation that was at work..
in such a case, the distorsion is not seen as non linear, although the
original signal is distorted, as a frequency is changed..this doesn t of course
appear as a classical non linear distorsion..
anyway, it s not the point fiercely defended by federmann, he s arguing
about absolute phase shifft as a distorsion, which is quite discutable...
 
The change of shape in Federmann's image is a result of a non-linearity, not a result of a phase shift. Thus his reasoning is pointless.

PMA ignores Addiction Vdif

Example 1
The frequency of 100Hz, amplitude 1V, gain 20dB, gain without feedback 80dB, output voltage 10V, Vdif 100μV,
phase 0 °
arcsin (Vdif / U(a)
arcsin = 0.00001 = 0,0005,73 °
Power 4Ω 25W, about 0.00005% THD

The frequency of 100kHz, 1V amplitude, gain 19 dB, output voltage 9V, gain without feedback 39 dB, Vdif 100mV,
Phase 5.74 °
arcsin (Vdif / U(a)
arcsin 0.1 = 5.74 °
Power 4Ω 20W, about 0.005% THD


Example 2
Acoustic signal 100Hz + 1 period 100kHz
Peak, rising edge, falling edge, always different.
Amplifier suppresses 100kHz -1dB, Vdif large 100mV, input transistors in the non-linear, the emergence of mutual modulation of signals. Distortion is non-periodic, distortion is heard, how much bias?

Distortion is generated by rapid changes. Distortion is not measured at a constant signal. The human ear hears what does not belong there.
 
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Federmann... do you have a complete workable design you can show us, for an amplifier that doesn't distort in the way that you claim... and if so, does it sound "different" or "better" than other designs.

It is very difficult to follow what you mean :)

Show us a fully workable design and why it is different and we may understand better.
 
Harmonic distortion... because (extra components) are what have been added to make it "out of shape"

If I amplify by 2 the output shape is not the same as the input shape, I have not added any extra frequencies or noise, well may be I have by mistake, but what I really have done is multiply by two. I could have a circuit where I compress a little bit thus changing the shape again. And perhaps this operation of amplifying or compressing or otherwise operating on the curve may produce harmonics or noise, which we can count and sum with THD but how do we measure and express the differences in the primary shape?

Or to put it another way, if someone says "THD 10% at 10W" does that mean that I have 10W of power at the output where 1W is frequencies that were not ever present and the rest 9W is the needed sinewave? But will it really be a sinewave and will it look exactly like the input? Or will it look different? Because if it looks different then we have plenty more "distortion" that we are not accounting for.
 
Federmann, do you hear one period of 100 kHz, which modulate 100 Hz signal ? If yes, so you are probably dolphin or your amp have really poor recovery time....

I gave an example.



Look here, looks like the spectrum trumpet 465.4 Hz. Watch how many there harmonics.
rozsah%20trumpety_2.gif
 
Federmann... do you have a complete workable design you can show us, for an amplifier that doesn't distort in the way that you claim... and if so, does it sound "different" or "better" than other designs.

It is very difficult to follow what you mean :)

Show us a fully workable design and why it is different and we may understand better.

Dear Mr. Federmann, would you mind kindly answer this question of Mooly?
 
Federmann, I have known the Boyk's paper for several years.

There are still questions about audibility of ultrasound, it seems to be audible only together with sound below 20kHz, as an ear intermodulation.

Anyway, you escape from the issue, and the issue is a real amplifier, measurements, listening comparisons. I can provide one of my amps to compare with the HQQF, do you agree?
 
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