Solid State Logic XLOGIC SUPERANALOGUE X-RACK Owner's Manual page 38

X-Rack Owner's Manual
LF EQ – Maximum Gain
Adjustment:
B.4.2 Output Balance
Equipment Required:
Test Signal:
Input and Output:
Unit Setup:
Adjustment:
B.4.3 'Balance' Adaptor
For the output balance adjustment, a 'balance'
adaptor such as that illustrated here will be
required. This adaptor consists of a pair of
close tolerance resistors in an in-line cable and
is used to sum together a balanced output in
order to correctly adjust the level balance of the
measured output; perfect balance should result
in complete signal cancellation.
Page B-6
1. Set LF Gain to maximum and select LF
80Hz and adjust LF Frequency to find the maximum level on the audio
level meter.
2. Adjust VR14 (LF Q) for +16.5dBu ±0.25dB.
3. Reset LF Gain to its centre indent position, de-select LF
the audio level meter for 0dBu.
Calibrated audio oscillator, audio level meter and a 'balance' adaptor (see
below).
1kHz sine wave at +24dBu.
Oscillator to the Input of the channel being tested, Output to the level
meter via the 'balance' adaptor.
Ensure that all front panel switches are off and all controls are set fully
anti-clockwise.
Connect the test equipment to the each channel in turn and adjust VR15
(BAL) for minimum level (< 55dBr).
From unit
under test
1
0V
5K01**
2
+
5K01**
3
–
1.
Note Resistor tolerance should ideally be 0.01%
2.
Absolute level measured will depend upon the input
impedence of the measuring equipment.
. Set the audio oscillator for
and re-check
3
–
1
2 To measuring
+
equipment
1
1
0V
2