Alto APM80.1000 Service Manual page 25

The error of the above test is +/-3dBu, among them the LEFT and RIGHT of CH7-8 and
CH9-10 all need to be tested.
4. MAIN 9-BAND EQ TEST
Input -40dBu BAL signal form the CH1, adjust the LEVEL and make the MAIN OUT is equal
to 0dBu, the AP scan setting is as follows:
1. When all the sliders are turned to the midpoints, the curve is as shown in the following
figure 1.
2. When the sliders of 50, 250, 1K, 5K and 16K are turned to the bottom, and 100, 500, 2K5,
8K to the top, the curve is as shown in the following figure 2.
3. When the sliders of 50, 250, 1K, 5K and 16K are turned to the top, and 100, 500, 2K5,
8K to the bottom, the curve is as shown in the following figure 3.
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