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Chapter 42 Audio Fundamentals 589
VIII
Sample Rate
The sample rate is the number of times an analog signal is measured—or sampled—
per second. You can also think of the sample rate as the number of electronic
snapshots made of the sound wave per second. Higher sample rates result in higher
sound quality because the analog waveform is more closely approximated by the
discrete samples. Which sample rate you choose to work with depends on the source
material you’re working with, the capabilities of your audio interface, and the final
destination of your audio. It is always better to start with a higher sample rate, even if
you are going to reduce to a lower sample rate later.
For years, the digital audio sampling rate standards have been 44,100 Hz (44.1 kHz) and
48 kHz. However, as technology improves, 96 kHz and even 192 kHz sampling rates are
becoming common.
In general, higher sampling rates are better than lower ones, but there is a threshold at
which higher sampling rates don’t yield noticeably better results. The ideal sampling rate
is still a widely debated topic among digital enthusiasts, and many analog proponents
shun digital technology altogether because no matter how high the sample rate, some
information is always missing. The best test is to listen for yourself and decide.
Audio sample rates When used
8 kHz–22.225 kHz These lower sample rates are used strictly for multimedia files.
32 kHz 32 kHz is generally used with 12-bit audio on DV.
44.1 kHz This sample rate is used for music CDs and some DAT recorders.
48 kHz DV, DVCAM, DVCPRO, and Digital Betacam all use this sample rate.
88.2 kHz A multiple of 44.1 kHz. This is useful for high-resolution audio that
needs to be compatible with 44.1 kHz. For example, if you
eventually plan to burn an audio CD, this sample rate is a good
choice.
96 kHz A multiple of 48 kHz. This is becoming the professional standard for
audio post-production and music recording.
192 kHz A multiple of 48 and 96 kHz, this is a very high-resolution sample
rate used mostly for professional music recording and mastering.