Yamaha IM8-32, Service Manual

Page: 112 / 307

IM8-40/IM8-32/IM8-24
112
2-13 Residual Noise
In the state described in section 2-1, set all the Fader and Level controls of each input CH to MIN and set all the ASSIGN switches
and CH ON switches to OFF. Then, the noise level when the Fader or Level controls of the MASTER is set to MAX or MIN shall
be less than the level speci
fi ed in the Table 2-13-1.
Table 2-13-1 [dBu]
FADER/control ST L/R OUT MONO OUT GROUP1–8 OUT AUX1–8 OUT MONITOR OUT MATRIX OUT PHONES OUT
MAX -72 -71 -73 -67 -72 -87 -77
MIN -98 -98 -100 -98 -99 -97 -100
* The switches for the STEREO, MONO and GROUP output shall be turned ON.
2-14 Phase
In the state described in section 2-1, the phase of the signal at each INPUT and the phase of the signal at each OUTPUT shall be
the same.
Check that the phase is reversed when the φ switch of the CH INPUT is turned on. Check also that the difference in level between
ON/OFF of the φ switch is within ± 1 dB.
2-15 LAMP
Connect a 30 Ω load resistor (5 W or more) between the pin 3 and 4 of the LAMP (12 V) connector.
The voltage between the pin 3 and 4 shall be 12.0 ± 1 VDC.
2-16 USB
2-16-1 Recording
With the settings as in the Table 2-16-1, record onto a personal computer via USB.
Table 2-16-1 [dBu]
INPUT INPUT level CH1 PAN control
L
PHONE
(INSERT)
1 -20.0
L (Turn fully counterclockwise)
R R (Turn fully clockwise)
* Turn on the REC OUT ST ASSIGN switch.
2-16-2 Gain
Check that output level is within the level in the Table 2-16-2 when the recorded fi le is played back via USB.
Table 2-16-2 [dBu]
MONITOR OUT L MONITOR OUT R
L 0 ± 3 –
R – 0 ± 3
* Set the Windows volume control to MAX.
* Turn on the PFL switch.
2-17 MUTE
In the state described in section 2-1, input signals to the MONO INPUT with respective ASSIGN switches turned on so that the
output level at the ST OUT is +20 dBu and check that the MUTE MASTER 1 LED lights up when the MUTE 1 is turned on.
Check also that the CH ON LED stops lighting and that the noise level is -60 dBu or less when the MUTE MASTER 1 is turned
on.
* Set the PAN/BAL to center.
Check the MUTE 2, MUTE 3 and MUTE 4 as well.
Next, check the ST INPUT (L, R) in the same way as the MONO INPUT.