Re: New FreeBSD port ALSA to JACK MIDI, a2jmidid

From: Hans Petter Selasky <>
Date: Sat, 12 Feb 2022 13:07:03 UTC
Hi Florian,

On 2/12/22 12:52, Florian Walpen wrote:
> Hi Hans Petter,
> On Friday, February 11, 2022 4:45:24 PM CET Hans Petter Selasky wrote:
>> My plan for MIDI support in FreeBSD is to use ALSA MIDI in user-space
>> via CUSE. It has some pros and cons, but mostly pros. The a2jmidid fills
>> the last hole, that JACK applications will automagically see USB MIDI
>> devices.
> I don't fully understand the implications of your proposal. Would it replace
> the current /dev/umidi* devices and audio/jack_umidi? Or is it just another
> option?

alsa-seq-server opens all available /dev/umidi* devices, so it is not 
compatible with audio/jack_umidi. You have to choose.

> Does it have an impact on usability or latency (or latency correction)?

No, jack is already slow, so no implications here.

> Frankly I'm not too familiar with the whole interaction between JACK, ALSA
> MIDI and alsa-seq-server. I suppose the alternative would be a better
> integration of jack_umidi with device detection? Or do we have to go through
> the alsa-seq-server anyway for applications like QTractor?

My idea is to have one MIDI server (ALSA based) to allow the same MIDI 
device to be shared by multiple devices. Also applications can create 
virtual ports. Yeah, MIDI is a bit complicated. Too many APIs.

>> Can be used together with latest version of:
> I never used midi hardware for anything serious, but I'll give it a test drive
> this weekend.