Prana Ferox
Addicted to Fun and Learning
Isn't the assumption that distortion is additive and you're unavoidably going to spend your"'can't hear it" budget in your signal chain in the speakers, so you want the rest as clean as possible?
Can anyone confirm, or supply a more general equation for calculating overall system SN/DR from the sum of it's components? (Just curious).
this is actually true of most electronics, distortion goes up with level. At low levels noise dominates. As the input or output level increases the distortion increases faster than the signal.@Frank Dernie
Secondly, unlike most electronics, loudspeaker distortion is almost always highly level-dependent. When speakers play softly, they produce less distortion, and when they play loudly, they produce more distortion.
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So have I and many others, that is why I thought it was worth having it all in one thread, and particularly since nobody has satisfactorily (to me at least) explained why one rule for speakers and a different one for electronics is OK from a SQ pov, I understand making low distortion even frequency response electronics is relatively trivial and getting anywhere near with speakers impossible but that is a practical rather than SQ matter.I have discussed this in several speaker review threads.
this is actually true of most electronics, distortion goes up with level. At low levels noise dominates. As the input or output level increases the distortion increases faster than the signal.
Very nice - thank you!I think what you're looking for can be found here (with a bonus calculator if you scroll to the bottom of the page).
What do people think?
My experience tells me the SNR needs to be better than -80dB for it to be inaudible (to me) listening to music and I had accepted the old limit (around for 50 years+) that better than 0.1% distortion (-60dB) was inaudible,
I agree, with a small addition, 0.1% distortion should have decaying profile of the distortion spectrum. That means, the distortion profile should NOT look like the one I am posting and is much more tolerable if it contains only low order harmonics.
I don't know if that's true or not, but how about this theory, that I'm not that convinced by.nobody has satisfactorily (to me at least) explained why one rule for speakers and a different one for electronics is OK from a SQ pov
I really don't think the only options are orchestral music and ear bleeding rock shows. How about someone playing an acoustic guitar amped so everyone in the room can hear it? That sound is being played through speakers that have characteristics and those characteristics are part of the live show. Yes for making a live album the microphone recording it may be "better" than the speakers used to play for the audience but which is more "real"?Well the live shows I go to tend to be orchestras and not amplified but with ear bleeding level rock concerts the sound includes the distortion, why should reproduction add more?
I agree, certainly my speakers distort far more at certain frequency's and at certain SPL levels, no doubt. The question is what level is audible with music (test tones are for testing and that is great, if I can't hear it with music then I ultimately don't care)Look, there's never been any doubt that even great speakers produce orders of magnitude more distortion than good electronics.
But it's important that when people consider/discuss a particular level of distortion, they don't do it in an SPL/frequency/harmonic order vacuum. Distortion audibility thresholds vary wildly depending on:
50% 2nd harmonic distortion @ 110dB / 40Hz is almost certainly inaudible with any signal.
- SPL
- frequency
- signal
- harmonic distortion spectrum
0.1% 3rd, 4th or 5th harmonic distortion @ 70dB / 1000Hz is likely to be audible with at least some signals.
I don't know if that's true or not, but how about this theory, that I'm not that convinced by.
You have a DAC, amp and speakers that each only generate 2nd and 3rd harmonic distortion. When you feed the signal through the DAC it adds 2nd and 3rd to the input, then the amp adds 2nd and 3rd to it's input, which included the 2nd and 3rd from the DAC, so you now have 2nd, 3rd, 4th 6th and 9th added to the original signal. Now feed that though the speakers and you have 2nd, 3rd, 4th, 6th, 8th, 9th 12th, 16th, 24th and 27th. The levels with be low for the later ones, but the harmonic spray is different from the start point which if audible may be less pleasant than simple 2nd or 3rd, changing to very low distortion DAC or amp cascades the improvements through the chain, giving the speaker less to distort.
I mean isn't what you say the point of this site? That a lot of money is being spent of snake oil and audio charms? Man I want to get into some blind tests and see what I really hear.And then there is the Benchmark crowd... Lots of amplifiers from 30 years ago had a SINAD of 65 db and everyone thought they were transparent then. Noise floor is only a problem with low efficiency speakers and desktop setups. My XLS1502 has a SINAS of around 76. Connected to LS50's my ear has to be within 3 or 4 inches of the speaker cone to hear the noise floor, and I get a built in high pass filter to boot.