Yamaha RIO3224-D Service Manual page 71

■ INSPECTIONS
1. Preparations
1-1. Settings
The ANALOG test of the test program is used for the
ANALOG IN/OUT characteristic test. Refer to Test Program (p.
47) for the settings that enable execution of the Test Program.
1-2. Measuring instruments
Use measuring instruments which can measure the check items
accurately with confi dence.
The input impedance of the measuring instrument should be
100 kΩ or more.
• Level meter
• Frequency counter
• Distortion meter
• Oscillator
• System Two
1-3. Parameters
Unless otherwise specifi ed, the parameter settings should be as
follows.
• Set the Word Clock to 96 kHz slave.
• 0 dBu = 0.775 Vrms
• 0 dBFS = 0 dB, full scale
• Set the "+48 V Master" to ON.
• Set the analog output loads to 600 Ω for each channel.
• When measuring the noise level and the crosstalk between
adjacent channels, use a 12.7 kHz, -6 dB/oct LPF and
correct by listening. For measurement, use the average
values and not root-mean-square values.
• Correct the distortion measurement with an 80 kHz,
-18dB/oct LPF.
• Set the oscillator output impedance to 150Ω.
2. ANALOG IN/OUT Test
2-1. INPUT 1 – 16 → OUTPUT 1 – 16
Parameters: Input analog signals from the CHn (n=1–16) input
and measure signals output from the CHn (n=1-16)
output. For the measurement procedure, refer to Test
Program Item [2-12 ANALOG Test] (p. 57)
1 Gain
Input
Input Level
Frequency
1 kHz +10 dBu
2 Frequency characteristics
Parameters: Parameters: 1 kHz is used as the reference of the
permissible range.
Input
Input Level
Frequency
40 kHz +10 dBu
3 Distortion
Input
Input Level
Frequency
1 kHz +4 dBu
1 kHz +22 dBu
4 Residual noise
Short INPUT to be measured with 150Ω.
Permissible
Range
–80 dBu or less
5 Level difference between channels
Confi rm that the range of difference in the gain measured in
item 1 above is as follows.
Permissible
Range
Within 1 dB
6 Crosstalk between adjacent channels
Parameters: Measure the noise level of odd number channels
and the adjacent even number channels on both
sides.
Short the input of the even number channels to be
measured with 150Ω.
Output Level
Input Frequency
(Odd Channel)
1 kHz +23 dBu
Perform the same check on the even number channels.
7 MUTE signal (OUTPUT 1)
With +4 dBu output at OUTPUT and MUTE turned on,
confi rm that the output level is -22 dBu or less at OUTPUT
1 as representing others.
Rio3224-D
Specifi ed Permissible
Output Level Range
+4 dBu +4±2 dBu
Permissible
Range
-1.5 – 0.5 dB
Permissible
Range
0.05 % or less
0.01 % or less
Permissible Range
(Even Channel)
-57 dBu or less
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