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can only be made via MIDI commands or from the RCU. To exit Lockout mode, send the MIDI unlock command
or press and hold the data knob for 5 seconds.
Group mode
m802 Group mode can be used when in MIDI control mode, but if a grouped channel’s gain is
changed from within Pro Tools® (or by a MIDI controller) only that channel will change. Pro Tools® does, how-
ever, have its own preamp channel grouping functionality.
A/D Converter Sensitivity Calibration
The m802 A/D Converter (AT112 Rev B and higher) features two independent calibrations for input sensitivity.
The software interface allows the user to easily switch between these two calibration settings. Each of the two
sensitivity settings (A) and (B) can be configured for one of four standard sensitivities. The following sections
detail the operation and calibration of this feature.
SelectinG tHe a/D SenSitivity
In order to access the A/D Sensitivity Setup menu, the m802 must be powered down. Once off, press and hold
the PEAK button and turn the preamp back on. After the system initializes, the ADC Sensitivity Setup menu will
be displayed. This menu has two columns. The left column is used to select the current A/D sensitivity setting
under the “ADC Sensitivity” menu item and the right column is used to select the actual sensitivities to be used
in each setting.
In addition to showing which configuration is selected (A) or (B), the calibrated sensitivity is shown in terms of
both a maximum analog level as well as the corresponding digital headroom figure. To toggle between the
two available sensitivity settings, click the encoder while “ADC Sensitivity” is highlighted. Rotate the encoder
clockwise to select the (B) calibration or counter clockwise to select the (A) calibration. Once selected, click the
encoder button again to exit the parameter edit mode. Turn the encoder until “DONE” is highlighted and click
the encoder. The m802 will reboot and the A/D converter analog input section will reconfigure for the new
sensitivity selection. Once set, the selected sensitivity is stored and remains active until it is changed by the user.
calibratinG tHe a/D SenSitivity
The m802 ships with the following two default sensitivity calibrations:
(A)+22dBu = 0dBFS (18dB Headroom)
(B)+18dBu = 0dBFS (14dB Headroom)
Internal trim controls allow you to reconfigure either (or both) of the sensitivity levels. Four standard sensitivi-
ties are supported in the m802 A/D converter.
+18dBu = 0dBFS (14dB Headroom)
+20dBu = 0dBFS (16dB Headroom)
+22dBu = 0dBFS (18dB Headroom)
+24dBu = 0dBFS (20dB Headroom)
recalibratinG for a Different a/D SenSitivity
The procedure in this section configures the m802 software:
1.
Power down the m802.
2.
Remove the 8 top cover screws using a #2 Phillips driver. Lift the top cover off the unit and set it aside.
