Moinmoin,
as I tried to help Mark regarding his "Logic-problems" in another thread, I will keep this to "MIDI feedback":
Imagine a sequencer (Logic, Ableton, or a decent hardware) connected to the Synthesizer like this:
- sequencer MIDI out -> synth MIDI in
- synth MIDI out -> sequencer MIDI in
You will want this, if You want the sequencer to record everything You play on the synth
and the synth to play everything the sequencer tells it to.
You will however not want to get an eternal loop like this:
- strike a key on the synth -> synth plays it and sends it to the sequencer (synth MIDI out -> sequencer MIDI in)
- sequenecer sends this same note as MIDI command to the synth (sequencer MIDI out -> synth MIDI in)
- synth plays the note from the sequencer and sends it to the sequencer (synth MIDI out -> sequencer MIDI in)
- ... You get it ...
- ... go on forever ...
If You change a parameter, the only difference is the MIDI command: It is no longer "note on" but "CC##" or "NRPN##", the eternal loop will be the same. So You have to break this loop somhow...
This may be done at the synth' as well as the sequencer's side.
On the synth this may be done by breaking the connection between keyboard / control knobs and modules (sound and modulation facilities)
"local on" enables this connection
"local off" breaks this connection
If you break this connection You may concider Your synth as divided into independent "master keyboard" and "sound module"
The example above is changed to:
- strike a key on the synth -> synth does not play it, as the connection between keys and controls is broken, but sends it to the sequencer (synth MIDI out -> sequencer MIDI in)
- sequenecer sends this same note as MIDI command to the synth (sequencer MIDI out -> synth MIDI in)
- synth plays the note from the sequencer and does not send it to the sequencer as keypress is decoupled from sound source (synth MIDI out -> sequencer MIDI in stays quiet)
Keep in mind however, that the synth will stay perfectly quiet, if You disconnect one of the MIDI cables: The only connection between the synth's controls and keys to sound and modulation sources is routed via the sequencer!
On the sequencer this may be done by stopping it to "echo" the commands received via its MIDI in to its MIDI out (my old KAWAII Q80 names this parameter "MIDI echo")
"MIDI echo on" forwards everything from MIDI in to MIDI out
"MIDI echo off" does not forward anything from MIDI in to MIDI out
The example above is changed to:
- strike a key on the synth -> synth plays it and sends it to the sequencer (synth MIDI out -> sequencer MIDI in)
- sequenecer records the command but does not send it back to the synth (sequencer MIDI out disabled for everything from sequencer MIDI in)
With both methods, the sequencer will send everything it "creates itself" to the synth and the synth will send any keypress and any parameter change to the sequencer (if You did not disable commands e.g. in the prophet's global menu [CC and/or NRPN off]).
While both ways break the loop, this happens in different ways at different places. The method to use depends on the entire MIDI setup. As long as You only use
one sequencer and
one synth, both methods will work the same way. I suggest to set the sequencer to "MIDI ocho off", however in order not to be surprised by a quiet synth if You use it solely
If You start to use a more complex MIDI installation, You will have to learn a little bit of "MIDI system architecture" anyway...
HTH
Martin