Ralf Mardorf wrote:
1.
I disconnected all audio connections for JACK and connected hw MIDI in
to hw MIDI out.
Is this connection through JACK or through ALSA, i.e., does it show up
in the output of "aconnect -l"? From what I understand, JACK's sample-
synchronous timing always adds latency, and might add period-related
jitter depending on the implementation.
Yamaha DX7 --> Alesis D4 results in a 100% musical
groove.
Yamaha DX7 --> PC --> Alesis D4 results in extreme latency,
With a single MIDI loopback cable, the latency test program tests
a "PC --> PC" connection. A more realistic test would be
"PC1 --> PC2 --> PC1" (or just one PC if it has two inputs and two
outputs).
Regards,
Clemens