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TEST PROCEDURE
3. THD+N Test
3.1 Place all unmeasured input Trim controls to minimum.
3.2 Rotate the channel 1 Trim control to maximum (fully CW). Apply a balanced 1 kHz, -41dBu sine wave
to the channel 1 XLR input.
3.3 Measure the THD+N level at the 1/4” TRS Main Output L and R jacks. It should be <0.05%.
3.4 Repeat steps 3.1 to 3.3 for the remaining inputs.
4. Noise Test
4.1 Rotate the channel 1 Trim control to maximum (fully CW). Apply a balanced 1 kHz, -41dBu sine wave
to the channel 1 XLR input.
4.2 Measure the Noise level at the 1/4” TRS Main Output L and R jacks. It should be < -75dBu.
4.3 Repeat steps 4.1 to 4.3 for the remaining inputs.
1/4” TRS Inputs 1 - 4 (T4S) or 1 - 8 (T8S) Tests
5. Gain Test
5.1 Rotate the channel 1 Trim control to maximum (fully CW). Apply a balanced 1 kHz, -22 dBu sine
wave to the channel 1 1/4” TRS input.
5.2 Measure the output level at the 1/4” TRS Main Output L and R jacks. It should be +12.5 dBu
+/-0.5dBu.
5.3 Repeat steps 5.1 to 5.3 for the remaining inputs.
6. Frequency Response Test
6.1 Rotate the channel 1 Trim control to maximum (fully CW). Apply a balanced 1 kHz, -22dBu sine wave
to the channel 1 XLR input. Reference a dB meter to the output at the 1/4” TRS Main Output L and R
jack.
6.2 Change the input frequency to 50Hz. Measure the output level at the 1/4” TRS Main Output L and R
jacks. Verify that the output level is 0.0dBr +/-0.5dBr.
6.3 Change the input frequency to 20kHz. Measure the output level at the 1/4” TRS Main Output L and R
jacks. Verify that the output level is 0.0dBr +/-0.5dBr.
6.4 Repeat steps 6.1 to 6.3 for the remaining inputs.
7. THD+N Test
7.1 Place all unmeasured input Trim controls to minimum.
7.2 Rotate the channel 1 Trim control to maximum (fully CW). Apply a balanced 1 kHz, -22dBu sine wave
to the channel 1 XLR input.