Adobe appears to have forgotten to publish the acceptable values for the flash.media.Microphone.rate property in the ActionScript 3.0 edition of their documentation.
The Adobe documentation on the rate (bitrate) property is limited to the following,
“The rate at which the microphone is capturing sound, in kHz. The default value is 8 kHz if your sound capture device supports this value. Otherwise, the default value is the next available capture level above 8 kHz that your sound capture device supports, usually 11 kHz. “
But, what If you want a rate (bitrate) other than 8 or 11 kHz ? If you are looking for the acceptable bit rates look no further. I dug this out of a tech note.
Sampling rate
Approximate data rate
5
5.512 kHz
1378 bytes/sec, or 11.025 K bits/sec
8
8.000 kHz
2,000 bytes/sec, or 16 K bits/sec
11
11.025 kHz
2756 bytes/sec, or 22.05 K bits/sec
22
22.050 kHz
5,513 bytes/sec, or 44.1 K bits/sec
44
44.100 kHz
11,025 bytes/sec, or 88.2 K bits/sec
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