XM6150/XM4220
24
INSPECTIONS
This test should be completed within 30 seconds of
starting.
(7) Channel Separation Test at 8
Ω
Load Resistance
Apply a sine wave of 1kHz at -5dBu to the input terminal
of one channel, set the output voltage obtained at the
reference level (0dB), and then short the input via a
600
Ω
resistance to the input terminal of another
channel which has been grounded. Check that the output
voltage from the other channel at this time is -60dB or less.
(8) Output Noise Level Test
Ground the input terminal via a 600
Ω
resistance, and
then check that the noise level generated at the output
terminal is as follows.
XM6150:
-68dBu or less
XM4220:
-66.5dBu or less
Be careful to avoid any effects from noise induced during
the inspection.
(9) Stability Test
Check that the following conditions are satisfied when
a rectangular wave of 10kHz at -10dBu is applied to the
input and a capacitor of 10pF to 0.47
µ
F connected
with a 4
Ω
load resistor in parallel.
Overshoot: Vp/Vo 1.8
Ringing:
Less than 5 waves
Next, when the load resistance is removed and the load
is only the capacitor of 10pF to 0.47
µ
F, check that the
overshoot is Vp/Vo 2.5 and that the ringing fades away
in less than 7 waves with no oscillation.
(10) Protection Circuit Test
First, check that the protection circuit operates and the
relay opens with 2 seconds when CN713 of the
REAR6(3/6) circuit board or REAR4(3/6) circuit board
is disconnected.
Next, check that the state does not return to normal
after the protection circuit has operated and CN713 is
re-connected.
After this, turn the power off and then back on again.
(11) Power Consumption Test
q
Check that the primary power is within the following
range when a sine wave of 1kHz at -10dBu is applied
to the input terminal.
XM6150: 360W
±
30W
XM4220: 330W
±
30W
w
Ground the input terminal via a 600
Ω
resistance,
and then check that the primary power is within the
following range.
XM6150: 40W
±
10W
XM4220: 30W
±
10W
(12) PC Limiter Test
Apply a sine wave of 1kHz and -7dBu to the input
terminal and connect a load of 1k
Ω
(
±
5%) to the output
terminal. Use an oscilloscope to monitor the output
terminal and check that the output is as follows.
XM6150:
Vp-p 20V
XM4220:
Vp-p 40V
1. Inspection in BRIDGE OFF mode
<Preparation>
Input attenuation:
0 (maximum)
Input terminal:
Cannon connector (Pin 2 HOT, pins
1 and 3 GROUND)
Input select switch:
EACH CH
[BRIDGE] switches: All OFF
Output terminal:
Load resistance 4
Ω
, non-induction
resistance, power capacity 500W or
higher
Other:
If there is no particular indication, all
channel operations should be active,
and inspection should be carried out
over all channels. In addition, if there
is no particular indication, the [HPF]
switch should be off.
<Inspection and adjustment>
(1) Fan Test
When turning on the power switch, check that the fan
operates at low speed.
(2) Power ON Muting Time Test
Check that muting is canceled and the [PROTECTION]
indicator is switched off for 2.5
±
1 seconds after the
power switch has been turned on.
(3) Output Terminal DC Voltage Test
Measure the output terminal DC voltage when the input
terminal is grounded, and check that the DC voltage Vdc
of the output terminal is 0
±
75mV.
(4) Gain Test
Check that the following output voltage is obtained when
a 1kHz, -10.0dBu sine wave is applied to the input terminal.
XM6150:
+22.1
±
0.5dBu
XM4220:
+23.6
±
0.5dBu
This test should be repeated after the input select switch
is moved from [CH A to ALL CH].
(5) Frequency Response Test
HPF SW OFF: Check that the response is within 0.0
±
0.5dB at 20Hz and within -0.5
±
0.5dB
at 20kHz using 1kHz as a reference when
sine waves at frequencies of 20Hz, 1kHz
and 20kHz at -10dBu are input to the
input terminal.
HPF SW ON:
Check that the response is within 3.0
±
1.0dB using 1kHz as a reference when a
sine wave at a frequency of 80Hz at
10dBu is applied to the input terminal
and the filter switch is OFF.
(6) Total High Harmonic Distortion Test
Check that the total harmonic distortion (THD) is 0.2%
or less at the following rated outputs when a high-quality
sine wave of 1kHz is applied to the input terminal.
XM6150:
150W x 6/4
Ω
(30.0dBu/ch)
XM4220:
220W x 4/4
Ω
(31.7dBu/ch)
Summary of Contents for XM4220
Page 4: ...XM6150 XM4220 4 ...
Page 20: ...XM6150 XM4220 20 A A to DRV6 2 5 CN410 to DRV6 1 5 CN402 PA6 Circuit Board ...
Page 21: ...21 XM6150 XM4220 A A Component side 3NA V416160 2 1 ...
Page 22: ...XM6150 XM4220 22 B B to DRV4 2 5 CN410 to DRV4 1 5 CN402 PA4 Circuit Board ...
Page 23: ...23 XM6150 XM4220 B B Component side 3NA V416170 2 1 ...
Page 26: ...XM6150 XM4220 26 ...
