if "harmonic distortion" stands for "additional harmonics" - then what do we call the "shape of output curve is not exactly the shame as the input curve" type of distortion?
Harmonic distortion... because (extra components) are what have been added to make it "out of shape"
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...
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.
quote :
"the emergence of mutual modulation of signals. Distortion is non-periodic, distortion is heard, how much bias?"
you must be more precise...which kind of mutual modiulation?
frequency modulation? phase modulation?.amplitude modulation?...
"the emergence of mutual modulation of signals. Distortion is non-periodic, distortion is heard, how much bias?"
you must be more precise...which kind of mutual modiulation?
frequency modulation? phase modulation?.amplitude modulation?...
thank you a lot...it s the first post where we can have a useful
clue about what you are talking about...
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.
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.
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 linked this very interesting discussion into Blowtorch thread 😉
http://www.diyaudio.com/forums/anal...rch-preamplifier-part-ii-317.html#post2021402
http://www.diyaudio.com/forums/anal...rch-preamplifier-part-ii-317.html#post2021402
amplitude modulation of two signals F1 and F2 create two new frequencies,
F1 + F2 and F1 - F2, wich to my knowledge is already counted as intermodulation
distorsion...so nothing new under the sun...
F1 + F2 and F1 - F2, wich to my knowledge is already counted as intermodulation
distorsion...so nothing new under the sun...
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.
I gave an example.
Look here, looks like the spectrum trumpet 465.4 Hz. Watch how many there harmonics.
wahab - there is a small difference in spectra of CCIF IMD and AM, CCIF 19+20kHz would have 19kHz, 20kHz and possible intermodulation products (1kHz, 18kHz, 21kHz etc.), though AM 19.5kHz carrier modulated by 500Hz would have 19kHz, 19.5kHz, 20kHz if no non-linearity is present, pus IM components with nonlinearity present.
Many, I wrote about it here and here and Caltech, Physiology, Array therapeutic
Music Professor James Boyk was a technical limitation to 102.4 kHz
Music Professor James Boyk was a technical limitation to 102.4 kHz
your site looks very interesting, mr federmann, sadly, i don t
read czekoslovakian....lucky pavel...
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?
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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