Modular Multitrack Recorder - Tascam

The MMR-8 has a built-in 1 kHz oscillator to check that the output levels are calibrated. To check the
output levels, select Setup Menu 530 and select the 1 kHz setting. Press STO to turn on the internal
oscillator. Make sure no tracks are selected in the Input mode, and then press the Play switch. Measure
the output levels and verify that they match the calibration settings (+4 dBu nominal=1.228Vrms,
measured at XLR pin 2(+) and 3(-) pins). If calibration is required continue to the MOC Calibration
Procedure.
MOC Calibration Procedure
Follow this step-by-step procedure to calibrate the MMR-8 Output Converters (MOC).
1. Turn off power and remove the top cover of the MMR.
2. Connect the audio analyzer input to the Output connector at the rear of the MMR.
3. Turn on the MMR. Wait for the software to load.
4. Generate the MOC calibration tone, a 1 kHz, -20 dBFS (of the digital bus) sine wave. To do this,
Press SETUP, and go to menu 530 by turning the Wheel. Press TRIM then turn the Wheel to select
the 1 kHz tone. Press STO to enable generation of the tone. Make sure no tracks are selected in the
Input mode. Press the PLAY (>) switch to start tone generation.
5. Set up the audio analyzer input to measure the output level on Output channel 1. Standard Calibration
level is digital full scale = +24 dBu. Pot adjustment range is digital full scale = +17 dBu to +25
dBu.(If there are special level requirements, those levels must be substituted for the levels in the
following steps.)
6. Locate the MIC and MOC card cage. Note on its cover that the Output board is identified, as well the
pot associated with each channel.
7. Using a plastic tweaker (supplied with the MMR-8), adjust the Output Ch1 pot to +4 dBu, +/-0.025
dB (=-20 dBFS.)
8. Move the audio analyzer input to the next MMR output channel. Repeat step 7. Continue until all 8
channels are calibrated.
End of the analog output level calibration procedure.
84
Tascam MMR-8 Owner’s Manual • Chapter 6 • Maintenance and Service MMR-8