- Thread Starter
- #41
please demonstrate with data.
It's in the charts of many amps, I'd say at least a third of them have higher third than second harmonic distortion
please demonstrate with data.
Is it, though? You need to do some reading about masking.It's self evident
Is it, though? You need to do some reading about masking.
Anyway I have done many blind tests regarding linear harmonic distortion and i never were able to tell below 1% THD in music. I think whatever you experienced was actually non-linear.
Think about this way, the second harmonic acts as the fundemental for the third harmonic (masking). So it's only possible to hear harmonic distortion when it's non-linear (third harmonic louder than second .etc) or if it was very high in output.
However with IMD things can build up to 10% rather quickly specially with bookshelf speakers. it's a much more valid concern.
The third harmonic isn't masked by the second. 1000hz to 2000hz is second harmonic, 3000hz is third. 3000 isn't double 2000
The sound energy in music in the 1-4khz range is 30-40db lower than bass, 15-30db than midrange.
I...do? I've done the tests myself with very low distortion equipment, speakers especially (ATCs and Neumanns, both of which average at 0.1% THD or lower in the midrange) - I can hear about 0.5% THD in program material which is far better than most (that's 50 dB down, by the way...). The way distortion works it's almost always low orders (i.e. HD2, HD3) dominating and the other ones fall away from that.It is in my experience. I guess I have experience with genuinely high fidelity gear, that might be a requisite.
Here's the spectrum of music I was listening to.
1-4 kHz range is about 20dB below bass and the song above had plenty of bass.
In electronics we see mostly 2nd or 3rd and at lower levels 4th and 5th.
Also keep in mind that instruments have lots of harmonics by themselves that are higher (and thus masking) than the ones produced by DACs and amps.
You can actually listen to distortion products when you null input and output of an amp.
Below a recent measured DAC
Now imagine the 1kHz were 50Hz and the 1-4kHz range was 20dB lower than the 0dB.
Then there would still be a distortion distance for the 5th harm (250Hz) of 105dB
Add to that music signals (incl harmonicsof the instrument itself) are just 10dB down and overpowering the distortion products by 95dB = 56000x times higher.
And the DAC above is not a special one.
When listening to music 70dB is about all the dynamic range your hearing can handle.
Play some music at impressive levels. Now attenuate 70dB... what do you hear ? and at -80dB or -90dB ? Why worry about anything below your hearing threshold ?
I...do? I've done the tests myself with very low distortion equipment, speakers especially (ATCs and Neumanns, both of which average at 0.1% THD or lower in the midrange) - I can hear about 0.5% THD in program material which is far better than most (that's 50 dB down, by the way...).
I think average might not be the best way to look at that, lower notes tend to be a lot more transient than higher notes.View attachment 160351
So here is the average spectrum of a bunch of commercial music between 1950 and 2010. At 1kHz is not even 20dB down from <100 Hz. Btw, source is AES paper 8960.
By definition, they are not.I think average might not be the best way to look at that, lower notes tend to be a lot more transient than higher notes.
How about you stop with the anecdotes and platitudes and actually demonstrate what you claim? If you actually want to convince people, that is the very best way.With very loud music on the second floor I can tell if my furnace is running. It isn't loud and it takes away detail. And the furnace is just noise, not harmonics which clash with the fundamentals in the music. Anecdotal of course
I think average might not be the best way to look at that, lower notes tend to be a lot more transient than higher notes.
Your spectrum is based on how many seconds of song? Since this just represent the peak levels of the whole time period, it can't really tell second to second bass to treble balance, correct?Here's the spectrum of music I was listening to.
1-4 kHz range is about 20dB below bass and the song above had plenty of bass.
In electronics we see mostly 2nd or 3rd and at lower levels 4th and 5th.
Also keep in mind that instruments have lots of harmonics by themselves that are higher (and thus masking) than the ones produced by DACs and amps.
You can actually listen to distortion products when you null input and output of an amp.
Below a recent measured DAC
Now imagine the 1kHz were 50Hz and the 1-4kHz range was 20dB lower than the 0dB.
Then there would still be a distortion distance for the 5th harm (250Hz) of 105dB
Add to that music signals (incl harmonicsof the instrument itself) are just 10dB down and overpowering the distortion products by 95dB = 56000x times higher.
And the DAC above is not a special one.
When listening to music 70dB is about all the dynamic range your hearing can handle.
Play some music at impressive levels. Now attenuate 70dB... what do you hear ? and at -80dB or -90dB ? Why worry about anything below your hearing threshold ?
OP's premise was that distortions several octaves higher were more audible due to our higher hearing sensitivity and lack of masking. However, OP has yet to provide an explanation on the mystical distortion mechanism that only generates harmonics that are "a few" octaves up and nothing else.0.1% in the same octave? No Problemo!
0.1% edit: a few octaves up? Turns into 10%. Problem!!!!!!
It's in the charts of many amps, I'd say at least a third of them have higher third than second harmonic distortion
Many audiophiles believe that 2nd harmonic is to be preferred over 3rd harmonic. Certainly it is simpler in character, and it is well agreed that orders higher than third are more audible and less musical. However when given a choice between the sound of an amplifier whose characteristic is dominantly 2nd harmonic versus 3rd harmonic, a good percentage of listeners choose the 3rd.
I have built many examples of simple 2nd and 3rd harmonic “types” of amplifiers over the last 35 years. When I say “types” I mean that they used simple Class A circuits described as “single-ended” versus “push-pull” and so tended to have a 2nd harmonic versus 3rd harmonic in the character of their distortion, but were not made to deliberately distort.
Anecdotally, it appears that preferences break out roughly into a third of customers liking 2nd harmonic types, a third liking 3rd harmonic, and the remainder liking neither or both. Customers have also been known to change their mind over a period of time.