Simple Midi Control; Loopback Detection - RME Audio Multiface User Manual

31.5 Simple MIDI Control

The stereo output faders (lowest row) which are set up as Monitor Main outputs in the Monitor
panel can also be controlled by the standard Control Change Volume via MIDI channel 1.
With this, the main volume of the Multiface is controlable from nearly any MIDI equipped hard-
ware device.
Even if you don't want to control all faders and pans, some buttons are highly desired to be
available in 'hardware'. These are mainly the Talkback and the Dim button, and the new moni-
toring options (listen to Phones submixes). Fortunately a Mackie Control compatible controller
is not required to control these buttons, as they are steered by simple Note On/Off commands
on MIDI channel 1.
The notes are (hex / decimal / keys):
Monitor Main: 3E / 62 / D 3
Dim: 5D / 93 / A 5
Mono: 2A / 42 / #F 1
Talkback: 5E / 94 / #A 5
Monitor Phones 1: 3F / 63 / #D 3
Monitor Phones 2: 40 / 64 / E 3
Monitor Phones 3: 41 / 65 / F 3
Preset 1: 36 / 54 / #F 2
Preset 2: 37 / 55 / G 2
Preset 3: 38 / 56 / #G 2
Preset 4: 39 / 57 / A 2
Preset 5: 3A / 58 / #A 2
Preset 6: 3B / 59 / B 2
Preset 7: 3C / 60 / C 3
Preset 8: 3D / 61 / #C 3
An example of a small MIDI controller covering such MIDI functionality (and even some more)
is the Behringer BCN44. This little box has 4 pots and 8 buttons for all the above functions –
for less than 60 Euros.

31.6 Loopback Detection

The Mackie Control protocol requires feedback of the received commands, back to the hard-
ware controller. So usually TotalMix will be set up with both a MIDI input and MIDI output. Un-
fortunately any small error in wiring and setup will cause a MIDI feedback loop here, which then
completely blocks the computer (the CPU).
To prevent the computer from freezing, TotalMix sends a special MIDI note every 0.5 seconds
to its MIDI output. As soon as it detects this special note at the input, the MIDI functionality is
disabled. After fixing the loopback, check Enable MIDI Control under Options to reactivate the
TotalMix MIDI.
User's Guide HDSP System Multiface © RME
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