PC9501N
28
■
INSPECTIONS
1.
Inspections in STEREO mode and PARALELL mode
1-1.
Preparation
1-2.
Inspection and adjustment
1-2-1.
Fan and POWER/PROTECTION LED
Turn on the POWER SW, then check that the PROTECTION LED lights in red and the POWER LED lights in green. Also
check that the fan runs at a low speed.
1-2-2.
Power ON muting time
Check that the muting function is cancelled at 9
±
3 seconds after turning on the POWER SW and the PROTECTION LED
turns off.
1-2-3.
Idling current (Adjustment)
Ground the input terminal, then adjust VR201 (A ch) and VR202 (B ch) so that the DC voltage (Vb) at No.1 and 2 terminals of
CN204 (A ch) and CN203 (B ch) is 0.1
±
0.05 mV.
Also, after all inspections, measure the Vb value again and adjust so that it is 0.1
±
0.05 mV.
1-2-4.
Output terminal DC voltage
Ground the input terminal, then measure the DC voltage (Vdc) at the output terminal and check that it is 0
±
50 mV.
1-2-5.
Gain
Feed 1 kHz, –10.0 dBu sine wave to the input terminal, then check that +22.1
±
0.5 dB output voltage is obtained.
Also perform this inspection in the PARALELL mode.
1-2-6.
Frequency response
• HPF OFF:
Feed 20 Hz, 1 kHz, 20 kHz, –10.0 dBu sine wave to the input terminal, then check that the output voltage at 20 Hz is within
0.0
±
0.5 dB and that at 20 kHz is within –0.5
±
0.5 dB as compared with the output voltage at 1 kHz.
• HPF ON:
Feed 20 Hz, –10.0 dBu sine wave to the input terminal, then check that the output voltage is within –3.0
±
1.0 dB as compared
with the output voltage at 1 kHz in the HPF OFF state.
1-2-7.
Total harmonic distortion
Feed 1 kHz high-grade sine wave to the input terminal, then check that the total harmonic distortion is 1% or less when the
output given in the table below is obtained.
Make sure to finish this inspection within 30 seconds.
Input attenuator
MAX
Input terminal
XLR-3-31 type connector, No.2: hot, No.1 and 3: ground
MODE SW
STEREO
HPF SW
OFF
Output terminal
Unless otherwise specified, load resistance: 8
Ω
non-inductive resistance, power
capability: 1 kW or more
DATA PORT
Unused.
AMP ID SW
1, 2, 4, 8, 16, T OFF
Others
Unless otherwise specified, both channels set for drive.
PC9501N
1000 W/8
Ω
(41.2 dBu/ch)
