Yamaha DME4io-ES Service Manual page 94

DME4io-ES/DME8i-ES/DME8o-ES
r Level difference between CHs
Confi rm the range of difference in the gain between each
CH [CH1 – 8 (4)] measured in item q above as follows.
[n=1 – 8 (4) Value in the parentheses ( ) is for measuring
DME4io-ES]
Permissible Range
Within 1 dB
t Crosstalk between Adjacent CHs
t-1. Crosstalk from Odd CHn to Even CHn+1
[n=1, 3, 5, 7 (n=1, 3)
( ) is for measuring DME4io-ES]
Measuring Method:
Terminate CHn+1 input with 150 Ω. Input the following
signal into the CHn input, and measure noise level at
CHn+1 output.
Input Frequency Output Level (Odd channel) Permissible Range (Even channel)
1 kHz +22 dBu ± 0.1 dBu
t-2. Crosstalk from Even CHn to Odd CHn-1
[n=2, 4, 6, 8 (n=2, 4) Value in the parentheses ( )
is for measuring DME4io-ES]
Measuring Method:
Terminate the CHn-1 input with 150 Ω. Input the
following signal to the CHn input, and measure noise
level at CHn-1 output.
Input Frequency Output Level (Even channel) Permissible Range (Odd channel)
1 kHz +22 dBu ± 0.1 dBu
y Maximum output
Input Frequency Input Level Permissible Range Permissible Range (Distortion Factor)
1 kHz +30 dBu +23 dBu or above
u Total Harmonic Distortion
Input Frequency Output Level
1 kHz +4 dBu ± 0.1 dBu
20 Hz +4 dBu ± 0.1 dBu
40 kHz +4 dBu ± 0.1 dBu
1 kHz +22 dBu ± 0.1 dBu
b. Use the test No. 2 and measure the following items.
q Voltage gain
Input Frequency Input Level Specifi ed Output Level Permissible Range
1 kHz -60 dBu
94
Value in the parentheses
-58 dBu or below
-58 dBu or below
0.01% or below
Permissible Range
0.05% or below
0.05% or below
0.05% or below
0.007% or below
+4 dBu +4 ± 2 dBu
w Frequency Characteristics
Measuring Method:
Set 1 kHz as datum, and measure a relative value for
each input frequency.
Input Frequency Input Level Output Level (Reference Value) Permissible Range
20 Hz -60 dBu
40 kHz -60 dBu
e Total Harmonic Distortion
Input Frequency Output Level
1 kHz +4 dBu ± 0.1 dBu
20 Hz +4 dBu ± 0.1 dBu
40 kHz +4 dBu ± 0.1 dBu
r Noise Level
Measuring Method:
Terminate CHn input with 150 Ω. Measure noise levels
output from the CHn output.
[n=1 – 8 (4) Value in the parentheses (
measuring DME4io-ES]
Permissible Range
-63 dBu or below
If the value does not fall within the permissible range
above, check that EIN (Equivalent Input Noise) =
Noise Level Measurement Value – (Voltage Gain at
1 kHz) -127
t Level difference between CHs
Confi rm the range of difference in the gain measured in
item q above as follows.
Permissible Range
Within 2 dB
2-6 Phantom DC Voltage Test
The object to be measured is the same as "2-5".
See the following for the measuring points and
method.
Use the test No. 13, connect as follows and take
measurements.
• Short-circuit the "+ terminal" and the "- terminal"
of CH1 and connect a 10 kΩ load between the
"- terminal" and the "GND terminal".
• Measure the DC voltage difference between the
"- terminal" and the "GND terminal" of CH1.
Permissible Range
DC 33 V – 36 V
Check that the voltage difference between the
"- terminal" and the "GND terminal" decreases
immediately when the test No. 14 is selected.
+4 dBu -1.0 dB – +0.5 dB
+4 dBu -1.0 dB – +0.5 dB
Permissible Range
0.1% or below
0.1% or below
0.1% or below
) is for