Yamaha MR816CSX Service Manual page 44

MR816CSX/MR816X
• Input signal
Use 1 kHz sine wave for input signal unless otherwise
specifi ed.
Input the following signals to the INPUT terminals.
System
Source
Impedance
• Setup of measuring device
Don't set up the filter of the measuring device unless
otherwise specifi ed.
• Notice
If a result of test related to noise (distortion, equivalent
input noise, crosstalk, mute, residual noise, etc.) is NG,
execute factory set and then test again.
(Refer to "FACTORY SET" on P. 40)
<2> Analog test
Set the MR816CSX/MR816X to the AD/DA through
setup (AD/DA, Digital Input/Output audio connection) for
checking. (Refer to " • Audio connection" in procedure
5-1-3-1 (P. 42))
<2-1> Gain (MIC input)
Set up the GAIN volumes [1 – 8] and [PAD] switches
as in the following table.
INPUT
INPUT
LEVEL
-16
MIC/LINE
INPUT
1 – 8
-60
INPUT
INPUT
LEVEL
-16
MIC/LINE
INPUT
1 – 4 -60
*1: Check that level differences between OUTPUT 1 –
8 channels and Headphones [1, 2] L/R channels are
as follows:
Tolerance
2 dB or less
<2-2> Gain (LINE input)
Perform the same test as the
<2-3> Frequency Characteristics
Set up as in description marked
procedure <2-1>.
44
MIC/LINE INPUT
1 – 8
Balance
150 ohm
Unit:[dBu]
OUTPUT
GAIN PAD
1 ‒ 8
MIN ON -22+/-2
←
MAX OFF +4 +/-2 (*1) ←
Unit:[dBu]
HEADPHONES
GAIN PAD
1, 2
MIN ON -32.9+2/-3
←
MAX OFF -6.9 +2/-3 (*1)
←
of procedure <2-1> .
1
2 4
and
Check that the level of each output when the
frequency is 20 Hz and 40 kHz are within the range
shown below compared with the level when the
frequency is 1 kHz.
Tolerance
Within +1/-3 dB
<2-4> Distortion
Set up as in description marked
procedure <2-1>.
Then, adjust input level so that output level is as in
the description below:
Check that the distortion of outputs is as follows:
OUTPUT
OUTPUT 1 – 8
Headphones 1, 2
OUTPUT
OUTPUT 1 – 8
Headphones 1, 2
* Use 22 Hz HPF and 30 kHz LPF.
<2-5> Equivalent input noise
Set up as in description marked
<2-1>.
Connect 150 Ω resistor to the input terminals as
follows:
MIC/LINE INPUT 1 ‒ 8:
1
2
Measure the output level at the [OUTPUT 1 ‒ 8]
terminals.
Check that the noise levels are as follows:
3
INPUT
4 MIC/LINE INPUT 1 – 8
* Use 22 Hz HPF and 30 kHz LPF.
<2-6> Output residual noise
Set up as in description marked
procedure <2-1>.
Measure output levels with no signal input.
Check that the noise levels are as follows:
Noise Level
* Use 22 Hz HPF and 30 kHz LPF.
in
1
and
Unit:[dBu]
LEVEL
+4
-6.9
Unit:[dBu]
Distortion
0.03% or less
0.1 % or less
2
in procedure
Between pin 2 (Hot) and pin 3 (Cold)
Unit:[dBu]
OUTPUT 1 – 8
-46 (EIN: -110)
1 and
Unit:[dBu]
OUTPUT 1 – 8 Headphones 1, 2
-80 or less -80 or less
3
in
3 in