Yamaha PX10 Service Manual page 55

2-2-2. Frequency Response
Measurement condition
Select "Analog > CFG1 （ +14dBu ） " with Service inspection mode.
Measured mode ／ 8Ω MODE
The sine wave of 1kHz, -11dBu is input to the input terminal,
and the output level of SP OUT is measured.
The sine wave of 20Hz, -11dBu is input to the input terminal,
and the output level of SP OUT is measured.
The sine wave of 20kHz -11dBu is input to the input terminal,
and the output level of SP OUT is measured.
2-2-3. Total Harmonics Distortion
Measurement condition
Select "Analog > CFG1 （ +14dBu ） " with Service inspection mode.
Measured mode ／ 8Ω MODE
When the sine wave of 1kHz is input to the input terminal, and the following
table outputs are obtained, total harmonics distortion is measured.
① PX10 500W 38.3dBu ② PX10 10W 21.3dBu
PX8 400W 37.3dBu
PX5 250W 35.3dBu
PX3 150W 33.0dBu
(half power)
※Use the low-pass fi lter of 20kHz for the measurement.
※Drive all channels.
2-2-4. Residual noise level
Measurement condition
Select "Analog > CFG3 （ E-VolMute ） " with Service inspection mode.
Measured mode ／ 8Ω MODE
The inputs of both Ach/Bch are terminated by 100 〜 150ohm resistor.
※Use the low-pass fi lter of 20kHz for the measurement.
PX8 10W 21.3dBu
PX5 10W 21.3dBu
PX3 10W 21.3dBu
(10W)
Criteria
Measurements are recorded as (A1).
The range of 0±1dB based on A1.
The range of 0±1dB based on A1.
Criteria
All channel
① THD=0.3% or less.
② THD=0.1% or less.
Criteria
All channel
PX10 -58dBu or less
PX8 -58dBu or less
PX5 -58dBu or less
PX3 -59dBu or less
PX10/PX8/PX5/PX3
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