Sonifex COURIER, User Handbook Manual

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Chapter 5 - Recording
Courier User Handbook 5-13
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Stereo Mix allows you to record in a stereo environment (Using left and right
inputs) but records the audio to disk in a mono format that has the information
from both the left and right channels combined.
5.7.3.4. Bit-rates
The Bit-Rate gives an indication of the amount of disk space used for the recording.
The lower the bit-rate selected, the higher the audio is compressed, the lower the
amount of disk space that the recording uses and the lower will be the quality of the
audio recorded. So, the highest quality mpeg recordings that can currently be made
are at 384kbps with the lowest quality recordings at 8kbps (kilo bits per second).
The default Mpeg Record Styles that are used with the Courier (CD Quality, FM
Quality, AM Quality, Tel Quality) can be used for recordings if you want to here
the difference between the different bit-rates.
To calculate the amount of compression that is being applied, multiply the sample
rate selected by 16 bits (recording depth) and then by 2 if a stereo recording is
being made. This will give you the actual bps of a linear recording. Divide by the
selected bit-rate to give the compression ratio.
For example, for a 32kHz stereo recording, at 128kbps, the actual bit-rate of a
stereo linear recording would be 32 x 2 x 16 = 1,024kbps, so the compressed
recording at 128kbps has a ratio of 1,024/128 = 8.
Courier supports the full range of bit-rates for both mpeg 1 layer 2 and mpeg 2
layer 2 recordings. The list of bit-rates that are available to you depend on the
sample rate and recording mode chosen. The following table indicates which
recording modes are supported (Both indicates Mono and Stereo) :
Sample Rate (kHz)
Data Rate
(kbit/sec)
16 kHz 22.05
kHz
24 kHz 32 kHz 44.1
kHz 48 kHz
8 Both Both Both N/A N/A N/A
16 Both Both Both N/A N/A N/A
24 Both Both Both N/A N/A N/A
32 Both Both Both Mono Mono Mono
40 Both Both Both N/A N/A N/A
48 Both Both Both Mono Mono Mono
56 Both Both Both Mono Mono Mono
64 Both Both Both Both Both Both
80 Both Both Both Mono Mono Mono
96 Both Both Both Both Both Both