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[InflatableMouse]

I've been trying to find a non-technical explanation of the effect samplerate has on the quality of sound. Most articles though fry my brain. I understand that samplerate is the limiting factor for the highest frequency as you need a minimum of 2 samples, so 44.1Khz samplerate limits a CD to 22.050Hz frequency, but there must be more to it than that . I just discovered my hearing stops at 15Khz. Not a real shocker as I had pierced eardrums several times. Once due to being too close to an explosion and several times due to heavy ear infections. Anyways ...

What I'm wondering, without getting into too much technical detail is will a tone, lets say 8Khz at the minimum samplerate sound just as good as on 10 times the samplerate?

To rephrase, what use is a samplerate more than double than the frequency you can hear?

Music isn't very often a single frequency, so for instance, does a higher samplerate help with more complex music, with lots of instruments for instance?

Thanks!

[mwillems]

I'm not a professional audio engineer, but I have fooled around with recording and reproducing sound.  The main advantage I found with higher sample rates for recording is that if you're doing a lot of signal processing, pitch shifting, etc. the sampling rate can make a huge difference in how the final processed clip sounds (higher sampling rate improved the subjective results when doing extended signal processing).  I don't know exactly why (as a technical matter) this was the case, but it was obviously different when there was less headroom.  I imagine it may relate to data redundancy? But that's kind of a shot in the dark.

I'm not sure what the advantage is of using a higher sample rate for playback, except perhaps for a desire for "bit-perfect" playback of recordings recorded at higher sample rates.  I personally cannot hear the difference between sample rates (above 44k) on otherwise identical program material (i.e. I have the same audio in different sample rates, and cannot distinguish them), but I've known some people who claimed to be able to do so.  

I'll second your question as to a good technical explanation of why higher sample rates would sound better for playback.

Edit:  Apparently some people think higher sample rate playback is actually harmful due to the risk of ultrasonic sound causing intermod in the audible range: http://people.xiph.org/~xiphmont/demo/neil-young.html.  

As an aside, I can't hear much above 16KHz myself, but I was using a compression driver that had an 8 dB peak at 19KHz for a while.  I found I kept getting mysterious headaches whenever I listened to music, often immediately, that went away as soon as I stopped the music.  After RTAing the system, I nulled out the 19KHz bump and my headaches went away.  So I couldn't hear it, but I could definitely "sense" ultrasonic sound, at least when it was that close to the audible range.

[Mikkel]

Hi,

I can't offer you quite what you request but you may find a lot of debate, education and entertainment by reading this thread at hydrogenaudio: http://www.hydrogenaudio.org/forums/index.php?showtopic=91302&st=0


Best regards
Mikkel

[InflatableMouse]

Hm that did answer the question quite well .

Thanks for that.

[mwillems]

Yeah that really does explain everything pretty well (including why higher rates are potentially useful for recording).  My thanks as well!

[mykillk]

I always up-sample my audiobooks to the highest multiple sample rate I can. I find audiobooks narration too slow so I like to speed up the playback rate. It definitely sounds better with up-sampling.

For everything else I play back at native sample rate because I find no difference in quality. So it kind of goes back to what mwilliems was saying, that up-sampling helps with applying dsp effects but other than that it's not very useful and can actually add unwanted noise.