playing MIDI: missing device interface

[Haines Brown]

I'm running debian squeeze and installed playmidi and a MIDI test file:

When I try to play the test file, I get:

$ playmidi testFiles/test.mid
Playmidi 2.4 Copyright (C) 1994-1997 Nathan I. Laredo, AWE32 by
Takashi Iwai
This is free software with ABSOLUTELY NO WARRANTY.
For details please see the file COPYING.
open /dev/sequencer: No such file or directory

Indeed, these return nothing:

$ ls /dev | grep sequencer
$ ls /dev/snd | grep sequencer

But I do have:

$ ls /dev | grep midi
admmidi
amidi
dmmidi
midi

Should I create a symlink from the midi interface to /dev/sequencer?

Haines Brown

[J G Miller]

On Wednesday, May 25th, 2011 at 13:27:36h -0400, Haines Brown wrote:

> I'm running debian squeeze and installed playmidi and a MIDI test file:

The problem is as far as I can tell as follows.

playmidi uses the old OSS interface /dev/sequencer.

Without loading the kernel module snd-seq-oss there will be no
/dev/sequencer interface file for playmidi to use.

The current ALSA modules distributed with the Debian Squeeze kernel do not
include the snd-seq-oss module which is the ALSA emulation of OSS for sequencer.

The answer to the problem is to install alsa source, specify use module assistant to
build the modules as a debian package, install the package and let the kernel
load the newly built modules from the updates directory.

However on trying this on a number of occasions, I have encountered the
showstopping error messsage that some symbol in the newly built modules
does not match the kernel version similar (but not identical to) that
reported at

<http://bugs.debian.ORG/cgi-bin/bugreport.cgi?bug=588385>

[Haines Brown]

> The problem is as far as I can tell as follows.
>
> playmidi uses the old OSS interface /dev/sequencer.

Thank you for this information. I installed playmidi to track a problem
I'm having with MuseScore. When I install timidity (which I should have
done in the first place), I have no trouble playing a test MIDI file,
and so I know my problem is with MuseScore.

Haines Brown

[J G Miller]

On Thursday, May 26th, 2011 at 07:35:35 -0400, Haines Brown explained:

> When I install timidity (which I should have
> done in the first place), I have no trouble playing a test MIDI file,

That is because timidity is a software MIDI player and does not use
any of the hardware on your sound card.

Incidentally, you do have a hardware sequencer on your sound card,
otherwise it is a little pointless in trying to followup on getting
the OSS sequencer emulation trying to work.

And I forgot to mention that instead of trying to use the older
(but in many respects better playmidi) you could just try to use
the ALSA native midi player, aplaymidi which will use the
ALSA device interface /dev/snd/%seq

You should try cat /dev/sndstat to see what abilities
are possible with your sound card, and also try running
aplaymidi -l to see if you have hardware midi playing
capabilities.

[J G Miller]

On Thu, 26 May 2011 12:40:50 +0000, J G Miller wrote:

> And I forgot to mention that instead of trying to use the older (but in
> many respects better playmidi) you could just try to use the ALSA native
> midi player, aplaymidi which will use the ALSA device interface
> /dev/snd/%seq

Something I forgot to add was that even if you are able to use aplaymidi,
you may not hear anything because you have to load a soundfont into the
hardware banks using asfxload (the ALSA version of the OSS sfxload), eg

asfxload $SFBANKDIR/General/8mbgmsfx.sf2

Obviously for specialized midi files, you may need to load additional
sound fonts into banks 1 ... etc in order to enjoy the full rendition
of the midi file as it was meant to be heard.