Appendix h - audio level calibration – 360 Systems MAXX-2400SD User Manual
Page 125

____________________________________________________________________________________
MAXX 2400 Owners Manual
Page 125
APPENDIX H - AUDIO LEVEL CALIBRATION
The input gain and output gain of the analog audio circuits are factory calibrated to a +4 dBu
standard. Each circuit includes a trim pot with a range of approximately ±2.5 dB. The following
procedures may be used to calibrate these for unity gain. The audio board must be partially
removed from the chassis to perform this procedure.
1. Power off the unit. REMOVE BOTH POWER CORDS
2. Remove the Chassis top by pressing the two blue release buttons, then sliding back and up.
3. The Audio board is the left most PCI card viewed from the front of the unit. Remove the
PCI hold down screw and rock the board up, being careful not to overextend the cables
attached to it.
4. Configure the jumpers according to the ANALOG setting. See Figure 53
Refer to Figure 53 for the location of trim pots and jumper blocks referred to in the calibration
procedures. Table 4 Indicates mapping to audio channels.
Figure 53 - Audio Board Trimpot Location
Channel
Input
Channel 1
Input
Channel 3
Output
Channel 1
Output
Channel 2
Output
Channel 3
Output
Channel 4
Connector
L
R
L
R
L
R
L
R
L
R
L
R
Trimmer
R10
R25
R40
R55
R71
R86
R101 R116 R161
R76
R191 R206
Jumpers
J1 and J2
J3 and J4
J5 and J6
J7 and J8
J11 and J12
J13 and J14
Table 4 - Jumper and Trimpot mapping
C2R - R116
C2L - R101
C1R – R86
C1L – R71
C3R – R76
C3L – R161
C4R – R206
C4L – R191
IN3R – R55
IN3L – R40
IN1R – R25
IN1L – R10