[LAU] Strnage MIDI behaviour

Ralf Mardorf ralf.mardorf at alice-dsl.net
Sat Dec 15 03:14:40 UTC 2012

Thousand years ago I build a MIDI thru box. On the board is a
potentiometer to adjust input sensitivity. The box worked fine with
synth, drum machines, Atari ST, C64 etc., but not with the PC. I guess I
never readjusted it, I didn't use it for a long time.
Perhaps replacing a resistor of the Waldorf's MIDI in does help in your
situation. IMO it's a myth, that the opto-coupler or the diode sometimes
are to slow.
If you've got parallel port MIDI, it might be better than the Envy's

PC MIDI does cause a lot of issues, e.g. that data can be transmitted
with a bad level. FWIW my PC is able to control all my synth, just the
MIDI thru box needs or needed a higher level.
Some synth need the MIDI status bytes all the times, then the software
has to provide the option to disable running status. For sure the
Waldorf is able to understand running status, it's just an example that
does effect other MIDI gear and I suspect it would be hard to find a PC
that is able to turn off running status.

If MIDI thru latency shouldn't be an issue, connect the MIDI out to
another synth and the MIDI thru of this synth with the Waldorf. Usually
one MIDI thru doesn't cause trouble regarding to latency.


More information about the Linux-audio-user mailing list