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I am looking at making some voice clips for teaching languages. I am using Audacity, but am not sure what settings to use. Many people recommend 44,100Hz for regular music recordings. Is this also the same for voice? Or does voice need a smaller sample rate? I will be recording as mono instead of stereo.

When saving as MP3 I have quality options: Insane, Extreme, Standard, and Medium. It is currently set to Standard. Would voice clips be okay on Medium or would Standard have a more clear sound?

I am trying to keep sound files as small as possible with the least amount of "noticeable" distortion.

Thanks!

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    Keep those settings, you're ok, i dont know if this needs a more detailed answer
    – frcake
    Jan 30, 2019 at 16:02
  • Will I notice a difference if I go lower than 44,100? I know there is a difference for music, but was wondering about voice as voice doesn't have quite the same range of sound.
    – kojow7
    Jan 30, 2019 at 17:16
  • A voice recorded through an ok microphone has a good amount of frequencies, there are complete musical arrangements made only with vocals. You shouldnt be concerned when using 44.1 (cd quality). If you're interested in what happens when you digitize sound, you should post another question.. the question's title doesn't really imply a full blown explanation of what happens when you quantize sound, and even if it did it would take a book to answer. 44.1 is industry standard. Lowering the sample rate a lot lower would at some point be unpleasant, but thats another topic i think..
    – frcake
    Jan 30, 2019 at 17:32

2 Answers 2

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Let's start with sound quality. Where are you setting the bar? Do your audio clips need to be simply clear and understandable, or do you want them to sound like a Hollywood voiceover? If it's the former, you can use lower sample rates and sacrifice some of the highest-frequency information for a reduction in file size.

In digital recording, frequency response is half the sample rate. A 32 kHz sample rate will preserve frequencies up to 16 kHz, which is above what the typical adult can even hear (and above what most mics will capture). A 22 kHz sample rate records up to 11 kHz, which still captures most of the clarity and sibilance in the voice. You can keep coming down, as a voice recorded with an 8 kHz sample rate can be clear and understandable enough for some applications.

The next main factor is file size. More compression equals more artifacts and, as you compress further, a loss of clarity. Lower sample rates create less data, hence your bit rate can come down. You're recording in mono, which allows you to further reduce your bit rate.

This is where you engage your ears with some test files. Experiment with sample rates to hear how the sound becomes less clear and "open" as you go down in frequency. Establish your minimum sound quality there, then start experimenting with compression bit rates. If you settle on 16 kHz mono for your recording, for example, start with a bit rate of 64 Kbps (nearly lossless at this sample rate). Drop your bit rate by about 10 Kbps for each recording until the gritty compression artifacts become unacceptable.

Eventually, you'll end up with a recording that represents an acceptable tradeoff between audio quality and file size. Hint: don't make your decision based on one playback system. Listen to your samples over a phone speaker, in earbuds, in a car, through a bluetooth speaker. Try to listen through every type of system your end users may use.

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Record PCM WAV at 48kHz.

16 Bit resolution is fine, although 24 bit is better if you are able.

Mono is fine.

The accepted convention for film/tv work is to record at 48kHz. For dialogue there is no need to use a higher sampling rate.

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  • This answer implies that 48 kHz is somehow "standard", which is not at all my experience. It is only standard when recording sound for film, except in cases where it has been supplanted by 96 kHz or 192 kHz. For music, 44.1 kHz was as close to a standard as there was for many years, now it's also mainly supplanted by 96 kHz, but some may use 88.2 kHz or 176.4 kHz. Feb 7, 2019 at 21:20

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