Jack-MIDI and Alsa MIDI Ports Connections

Post fully complete "how to" guides and tutorials here. This is a great place to get feedback on stuff you might put in the wiki.

Moderators: khz, MattKingUSA

User avatar
musicology
Established Member
Posts: 16
Joined: Mon Dec 20, 2010 5:00 am

Jack-MIDI and Alsa MIDI Ports Connections

Postby musicology » Fri Dec 31, 2010 5:36 pm

Hello,

I am using the Edirol FA-66 Firewire Audio Interface, which does also have one MIDI-Port. Now there is a problem with the Jack-MIDI and Alsa-MIDI ports in the Jack connections window, they are seperated. The Firewire-MIDI port shows up in the Jack-MIDI window. If you start an Audio/MIDI Sequencer like Rosegarden, it does only show the Alsa-MIDI ports, so you are not able to record and play a MIDI-device, which is connected to the Firewire-Interface.

Thus I searched the web and found the program a2jmidid, which builds a "bridge" between the Jack-MIDI and Alsa-MIDI ports. It can be started in the terminal with the following command for example: a2jmidid -e
output:
Bridge starting...
Using JACK server 'default'
Hardware ports will be exported.
port created: Midi Through [14] (capture): Midi Through Port-0
port created: Midi Through [14] (playback): Midi Through Port-0
port created: M50 [16] (capture): M50 MIDI 1
port created: M50 [16] (playback): M50 MIDI 1
port created: ESI KeyControl 25XL [20] (capture): ESI KeyControl 25XL MIDI 1
port created: ESI KeyControl 25XL [20] (playback): ESI KeyControl 25XL MIDI 1
Bridge started


Then there is another program, which is called Patchage, the screenprint of this window is attached. I connected with Patchage the MIDI ports of the sequencer, and then it was possible to play and record the MIDI device, which was connected to the Firewire-Interface.

So basically everything is working. However there is still a problem with the stability of such a system, Jack tends to stop whenever there is an "unusual" event.

Best Regards
Ralf
You do not have the required permissions to view the files attached to this post.

User avatar
musicology
Established Member
Posts: 16
Joined: Mon Dec 20, 2010 5:00 am

Re: Jack-MIDI and Alsa-MIDI Ports Connections

Postby musicology » Sat Jan 01, 2011 2:44 pm

Hi,

My Laptop (Macbook) has an Intel Core Duo, and the CPU frequency is switching from 1GHz to 1.83GHz depending on the requirements. When I set the frequency to max, which means 1.83GHz, then it does look like that the stability of the system with running all the applications is much better.

Best Regards
Ralf

zettberlin
Established Member
Posts: 116
Joined: Sun Apr 13, 2008 7:21 pm
Location: Celle
Contact:

Re: Jack-MIDI and Alsa-MIDI Ports Connections

Postby zettberlin » Thu Jan 06, 2011 1:29 pm

musicology wrote:Hi,

My Laptop (Macbook) has an Intel Core Duo, and the CPU frequency is switching from 1GHz to 1.83GHz


Freq-switching was often reported to be a problem for jack. I had good experiences setting the frequency lower then max by default though. So running the system at full throttle all the time is not absolutely needed.
nostrum fungitur


Return to “HOW TOs, Tips & Tricks”

Who is online

Users browsing this forum: No registered users and 2 guests