Studer 928 Service Manual

E 3/22 Alignment
928 Mixing Console
Edition:
07.02.01
3.3.5 Group unit 1.928.230
First, verify the jumpers according to the jumpers list in sec-
tion 3.1.3, in order to prevent the groups from routing to them-
selves (e.g. that group 1/2 can only be routed to all the other
groups, but not to group 1/2. Therefore, jumper J5 must not be
inserted).
Fader calibration:
• Feed test signal with nominal level (1 kHz, typ. +6 or +10 dBu)
to the LINE input of a mono channel.
• Route the signal to the group to be adjusted.
• Remove the Group unit from the console and reconnect it via
the bus adapter (optionally available; order no. 1.228.332.00).
• Set the LINE GAIN potentiometer to center position (CAL.),
switch filters off, and set the input and group faders to their
0 dB positions.
• Connect the unbalanced input of the AF voltmeter to the “after
fader” point of jumper J1, i.e. position 3.
• Adjust the measured level with trimmer potentiometer PR3 to
6 dB below nominal level because of the unbalanced meas-
urement.
Distortion:
• Connect the distortion analyzer to the corresponding group
output.
• Adjust with trimmer potentiometer PR5 to minimum distortion.
Group output level:
• Connect the AF voltmeter to the corresponding group output.
• Adjust the measured level with trimmer potentiometer PR4 to
nominal level.
Limiter distortion:
• Connect the distortion analyzer to the corresponding group
output.
• Activate the limiter/compressor section by pressing the LIM/
COMPR IN key.
• Adjust with trimmer potentiometer PR2 to minimum distortion.
Limiter level:
• Connect the AF voltmeter to the corresponding group output.
• Increase the input level with GAIN potentiometer by 10.2 dB
(nominal level +10.2 dB).
• Set the DRIVE potentiometer to its center position, and the
RATIO potentiometer to its maximum (limiter) position.
• Adjust the group output level with trimmer potentiometer PR1
to nominal level +0.2 dB.
Meter:
• If available, adjust the corresponding limiter meter to +10 dB
indication.
J2J3 J4J5
PR1
PR2
THRES- HOLD LIM/COMP
THD NULL LIM/COMP
J1
PR5
THD NULL FADER
J6 J7 J8
PR4
OUTPUT LEVEL
PR3
POST CAL
Main Board
1.928.230
(component side)

Studer 928 Specifications

General

Brand	Studer
Model	928
Category	Music Mixer
Language	English