Certainly logic dictates that a sampling rate of 44.1 khz cannot adequately work at frequencies over about 10khz, but, in fact, as Nyquist demonstrated, an audio wave can be accurately reproduced if sampled at a frequency up to but not including twice the highest frequency you want to reproduce. If you have a PCM processor, such as a Sony F1, and a scope, you can record a sine wave at 15khz and look at the reproduction on the scope and see a perfect sine wave. The reason is simply that if the wave, which is only sampled a little more than twice, were anything but a sine wave, and the system is limited to frequencies below 20khz, those 2+ samples would be different; the same applies to much more complex audio waves.
> From: Toby Seay <[log in to unmask]>
>To: [log in to unmask]
>Sent: Friday, August 17, 2012 11:04:42 AM
>Subject: Re: [ARSCLIST] Bit rates over 48 kHz
>Yes, 44.1KHz and 48KHz cover the entire hearing spectrum. However, it does
>not cover it well. Resolution gets worse as you go higher in the frequency
>spectrum. Therefore, really high frequencies only get sampled a few times.
>For instance, a 44.1KHz sample rate is only capable of sampling a 12KHz
>frequency 3.675 times a second. That leaves you with a very poor
>digitization at 12KHz. 96KHz does a much better job at providing a digital
>representation of higher frequencies.
>If you can, take a recording at 44.1KHz and high-pass filter it until you
>only have really high frequencies. You will clearly hear why lower sample
>rates are inadequate.
>Assistant Professor - Music Industry Program
>Antoinette Westphal College of Media Arts & Design
>Drexel University Audio Archives
>Macalister 3016 - 215-895-5880
>On 8/17/12 10:37 AM, "Henry Borchers" <[log in to unmask]> wrote:
>>I¹ve been wondering what the real benefits of archiving music and spoken
>>word at 96 kHz and above. From what I understand, NyquistShannon tells
>>us that the highest frequency we can hear on digital recording is half of
>>the sample rate, so 44.1 and 48 already covers the spectrum of our
>>I do know that high speed recordings at higher bit rate can be very
>>useful for when you are trying to transfer large volumes of long running
>>tape in a short time but I am curious what the rational and benefits are
>>for transfer real time at 96 kHz.
>>Broadcast Media Digitization and Curation Librarian
>>University of Maryland