few years ago I bought this keyboard MIDI (MK-3701) on ebay. It is purely a MIDI keyboard, speaker and generates no sound. To use it must be connected to a MIDI port as having the old sound cards.
On the other hand I have an old PC with a sound card Avance Logic ALS120 (semi-compatible with Sound Blaster 16). 
The first option was to directly connect the keyboard to the OPL3 synthesizer of the card (by rosegarden - ). But for some reason not working.
- The second option was to use a software synthesizer (timidity ) and use the PCM output. The problem is the CPU usage (is a PC with ISA bus ...) and the sound quality (this card seems to work in 8 bits).
- The option works best for me is to use my new laptop to synthesize sound. For this I have to send the MIDI over the network (at first I tried rosegarden and
- multimidicast ). The simplest and most efficient way to send MIDI events on the network is to use ALSA tools:
First run this on the old PC that has the keyboard:
aseqnet & # Launch MIDI server network
aseqdump-l # List of available devices (16:0 Avance Logic, 128:0 Net Client)
aconnect 16:0 128:0 # Connect the keyboard to input MIDI server .
then run it on the laptop: 192.168.1.10 aseqnet
& IP # Connect to the MIDI server
timidity-iA-OS1-B 2.3 & # Launch the software synthesizer (Note that you No assigned 128:0)
aseqdump-l # List of available devices (Net Client 129:0) 129:0 128:0 aconnect
If something goes wrong the first thing is to check that the sound is being sent over the network: Run both commands client # Connect MIDI synthesizer
After this I can already play the piano with low latency and high sound quality.
aseqnet
and to measure traffic on the network pusar keys (should rise to ~ 1 kb / s).
