Quantizing a song

CD-ROMs quantize sounds to 16 bits. In the demo above you may have been able to get to fewer than 8 bits before you heard the quantization noise. The next demo lets you listen to music.

Try this:

1. Click the Reload File List button on the demo below to see all the files you loaded at the start of this page.
2. Click on the 01Tone1000.wav file.
3. Click Play. You will hear a 1000Hz tone play.
4. Adjust the Quantization bits slider to hear the effects of quantization.
5. Click on the G.wav file to hear a music file. Does it need more or fewer bits than the 1000Hz tone so that the quantization noise isn't heard?

Another way to make sound files smaller is to sample them at a lower rate. The sampling theorem says you have to sample at 2 times the highest frequency. Therefore if you reduce the sampling rate, you reduce the highest frequency that can be reproduced.

Try this:

1. Reset the quantization bits back to 16.
2. While still listening to the music try adjusting the Sample Rate. The Spectrum plot below shows what frequencies are being produced. How low can you get the sampling rate and still have the music sound good?

Sorry, but the .Linux platform is not supported at this time.

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