Marantz SR7400 - Power Amplifier Adjustment Procedure; Idling Current Alignment

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9. POWER AMPLIFIER ADJUSTMENT
Idling Current Alignment
1. Each of the measurement points are provided with the two test points. Set a digital Voltage meter to DC voltage input,
connect the meter to the test points at both contact points.
2. After the setup above, turn on the main switch and heat up the amplifier about 10 minutes.
3. Adjust variable resistors (VR41, VR42…VR71) according to the digital voltmeter readings. The target setting value is 4.9
mV +/- 0.05 mV for each channels.
Settings : Master Volume --- Minimum
Speaker out --- No Load
Top lid --- OPEN
Channel
Alignment
Point
Measurement
Point
Front L VR41 CN41
Center VR61 CN61
Front R VR51 CN51
Surr. L VR42 CN42
Surr. R VR52 CN52
Surr. Back L VR62 CN62
Surr. Back R VR71 CN71
Time Table of Idling Current Rise
After Turning ON
Measurement Voltage
(CN**)
5 min. 4.5 mV
10 min. 4.9 mV
20 min. 5.5 mV
30 min. 6.2 mV
40 min. 6.8 mV
60 min. 7.0 mV