By "partial" what I mean is essentially an overtone or harmonic relative to the fundamental tone. For example, if a string vibrates in a number of modes e.g. 2f, 3f, 4f etc, these modes contribure partials to the sound of the string.
What I guess I'm saying is that there may be, for example, two 3f modes, 180 degrees out of phase with each other, that may be excited in a system (but maybe not at the same time) which when added to the fundamental results in a different waveshape but sounds identical.
There may be other effects like crest factor of the waveform that could cause a circuit to respond differently (as a second order effect) but it doesn't seem like human hearing can differentiate.
My experiments with the slide pots that anyone can now do by drawing waveforms in an editing tool e.g. soundforge are instructive in that there's no way to think of a sound and know what wave to draw. It's a lot more intuitive to build a timbre directly out of the partials.
An externally hosted image should be here but it was not working when we last tested it.
But your question makes me think of some systems where an upper partial may not be an exact multiple of the fundamental. This causes the vibratory mode to shift around, imparting a "gong-like" quality to the sound. I would imagine in this case the relative phase of the so-called enharmonic partials is constantly changing.
Well, I think I understand it if all those harmonics are to be seen as riding on the line of the fundamental, but as soon as I look at it as compressed air then I see the pulses of the harmonics traveling through the pulses of the fundamental and that would mean they divide them as they pass through - I think . . .
No, they all travel at the same speed, the speed of sound. If you think of them as compressions and rarefactions, then the 3rd harmonic will fit in three between the maxima (or any given point) of the fundamental. They all travel in ranks, like soldiers.
w
But the speed of sound is slightly greater in the densified parts of the wave, which causes the air itself to add it's own first order nonlinearity to the sounds (more f2 distortion to louder sounds).
Our ears also add some first order nonlinearity to louder sounds.
Many instruments and the human voice have overtone profiles biased toward first order nonlinearity
Single ended amplifiers in particular add more first order nonlinearity to higher signal levels.
Now I think that this first order nonlinearity is probably more natural sounding than other forms of distortion, if one has to have distortion.
Perhaps recording and reproduction systems which simply add some small amount of low order harmonic distortion are relatively benign compared with systems which add even smaller amounts of higher order distortion products.
Michael
Our ears also add some first order nonlinearity to louder sounds.
Many instruments and the human voice have overtone profiles biased toward first order nonlinearity
Single ended amplifiers in particular add more first order nonlinearity to higher signal levels.
Now I think that this first order nonlinearity is probably more natural sounding than other forms of distortion, if one has to have distortion.
Perhaps recording and reproduction systems which simply add some small amount of low order harmonic distortion are relatively benign compared with systems which add even smaller amounts of higher order distortion products.
Michael
For a few weeks now I've been playing with the Salas HV Simplistic reg. - most recently trying different things with the CCS section of the circuit. I again ran into this odd effect where having made a change, the sound is (so far) impossible to differentiate from that of the previous circuit version except that it doesn't touch me at all. I go through the check list and everything is the same except that in the one case I simply cannot care about the music. I can look at the speakers and know that the sound is there yet the moment I turn away from it nothing it offers seems to be taken up with interest by the ear. only the occasional blithe inner remark that it sounds "good".
This talk of sine relationships has me wondering again what the mechanism for that might be.
This talk of sine relationships has me wondering again what the mechanism for that might be.
What is the frequency response of the CCS? I wonder if a CCS is truly constant
when it comes to transients.
Michael, you should think of dynamics. The louder are sounds in the naked nature, the brighter they are. The less loud they are, the softer they are. Harmonic content in the nature depends on loudness.
On louder sounds reproduction system is allowed to add higher order of distortions, while on less loud sound it is not allowed.
Triode SE amp as if made to mimic the Mother Nature.
On louder sounds reproduction system is allowed to add higher order of distortions, while on less loud sound it is not allowed.
Triode SE amp as if made to mimic the Mother Nature.
Yes, you might be right about transient response or recovery. In several of the early versions I built that was the obvious problem - every obvious sharp transient had a little fuzz on it. But if that's the problem in the newer ones I can't hear it as such. I need to get a scope but for now my ears are doing all the work so I can't say more.
But my comment about the current source isn't about fixing it. It was triggered by what Michael has been talking about - particularly the bit about certain differences in partial phase relationships not being audible. I wondered if it might be the case that it would not be audible as an object but as the arising of say, a psychological effect.
Hello,
This topic started with harmonics coming from the resistors and possibly from the original CD. It then drifted to the angels and the ear.
If it is not the resonant piano string I say that the harmonics come from the cone and resonate speaker enclosure.
DT
All just for fun!
This topic started with harmonics coming from the resistors and possibly from the original CD. It then drifted to the angels and the ear.
If it is not the resonant piano string I say that the harmonics come from the cone and resonate speaker enclosure.
DT
All just for fun!
Flat-topping a sine wave will do it, too. Take a fundamental sinus, add its 3rd harmonic at 1/3 amplitude. Do this several more times and you will get a square wave. This works backwards, also. Ergo, you have the fundamental and it's generated harmonics contained in the distorted square wave.
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