Creative SB0350 Programming Manual page 75

Registers 0x3F/0x40 (Input Gain .L/.R)
Registers 0x41/0x42 (Output Gain .L/.R)
2 bits per channel, giving 4 levels.
0 to 3 0 dB to 18 dB, in 6 dB steps.
Default is 0
Register 0x43:0 (Mic AGC)
0 AGC on (default).
1 Fixed gain of 20 dB.
Registers 0x44/0x45 (Treble .L/.R)
Registers 0x46/0x47 (Bass .L/.R)
4 bits per channel, giving 16 levels.
0 to 7 – 14 dB to 0 dB, in 2 dB steps.
8 to 15 0 dB to 14 dB, in 2 dB steps.
Default is 8
Mixer Chip Programming
0 dB.
0 dB.
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