Yamaha Audiogram 3 Service Manual page 14

AUDIOGRAM3
2-11 Maximum output
Input signal to the INPUT1 and check that the distortion (T.H.D.) is 1.0 % or less when the output signal at the STEREO OUT L,
R is +14.0 dBu.
Check that the distortion (T.H.D.) is 1.0% or less when the output level at the PHONES L, R is 0.0 dBu.
* Set the LEVEL control of the INPUT2 to minimum.
* Do not connect a load resistor to the PHONES L, R when measuring the STEREO OUT L, R.
2-12 Equivalent input noise
Check that the noise level of the STEREO OUT L, R is -61.0 dBu or less when the pin 2 and pin 3 of the XLR terminal are
connected with the resistance of 150 Ω.
If the noise level is -61.0 dBu or more, check that the input equivalent noise level is -125.0 dBu or less.
* [Equivalent input noise level] = [Noise level] - [Channel gain]
* Set the LEVEL control of the INPUT2 to minimum.
* Use the 12.7 kHz, -6 dB/octave Low Pass Filter when measuring the noise level.
* Set the parameter of the analyzer to the "Mean value" when measuring noise level.
2-13 Residual Noise
Set the LEVEL control of the INPUT part to minimum.
Check that the noise level of the STEREO OUT L, R is equal to or less than the one shown in the [Table 2-13.1] when the LEV-
EL control of the "OUT" is set to maximum or minimum.
* Use the 12.7 kHz, -6 dB/octave Low Pass Filter when measuring the noise level.
* Set the parameter of the analyzer to the "Mean value" when measuring noise level.
Table 2-13.1 [dBu]
MASTER level STEREO OUT
control
Maximum
Minimum
2-14 USB
2-14.1 Recording
In the state of the [Table 2-14.1], record onto a personal computer via USB.
* For recording procedure, refer to "Recording using the Cubase AI 4" on page 18 or "Recording using the TWE" on page 28.
Table 2-14.1 [dBu]
INPUT
XLR 1
2-14-2 Gain
Check that output level at the STEREO OUT L, R is within a range of +14.0 ± 3.0 dBu when the recorded fi le is played back via
USB.
* Set the Windows volume control to maximum.
3. Phantom power
Connect the resistance of 4.7 kΩ (1W or more, margin of error should be 1% or less) between the pin 1 and pin 2 of the XLR
terminal and short circuit between the pin 2 and pin 3.
Check that the voltage obtained between the pin 1 and pin 2 is between +25.8 V and +29.8 V when the PHANTOM switch is
turned on (LED should light).
4. Initial setting
All volumes : Minimum
All Switches : OFF
14
L, R
-70.0
-98.0
Input level
-50.0