Default parameters in /etc/default/timidity make midi emulation slow

[Vincenzo Ciancia]

Binary package hint: timidity

In /etc/default/timidity there is

TIM_ALSASEQPARAMS="-B2,8 -Os"

which, at least in rosegarden, makes sound slow and noisy. I found that just

TIM_ALSASEQPARAMS="-Os"

performs really better on both my laptops. Could this be made the default since I think that timidity as an alsa sequencer is meant to be mainly used realtime?

[Luca Falavigna (dktrkranz)]

Thank you for your bug report. What is -B2,8 option meant to do?
This can be somehow related to bug #59029.

[Vincenzo Ciancia (vincenzo-ml)]

Bug 59029 seems to have nothing to do with my report since it's about some php stuff :) Maybe the correct number is another one. However I don't clearly understand what that option is for:

" -B n,m, --buffer-fragments=n,m
              For the Linux/FreeBSD/OSS/ALSA/Windows sound driver, selects the
              number of buffer fragments in interactive mode. Increasing the
              number of fragments may reduce choppiness when many processes
              are running. It will make TiMidity++ seem to respond sluggishly
              to fast forward, rewind, and volume controls, and it will throw
              the status display off sync. Specify a fragments number of 0 to
              use the maximum number of fragments available.
"

however it seems to me that "_may_ reduce choppiness" and "it _will_ make timidity++ seem to respond sluggishly" explain the situation very well: you get a disadvantage without any guarantee of an advantage. However, one should ask the original debian maintainer or whoever patched it in ubuntu, I mean who introduced that line, in case one wonders why it was introduced. Did you try both with and without that option on your machine, Luca?

[Luca Falavigna (dktrkranz)]

Whoops, it was bug #59092 :)
Anyway, I'll try to make some tests in order to confirm this bug.

[Luca Falavigna (dktrkranz)]

timidity (2.13.2-13ubuntu2) gutsy; urgency=low

  * Enable MIDI sequencer by default (LP: #59092)
  * Disable buffer fragments (LP: #82860)

 -- Luca Falavigna <email address hidden> Sat, 16 Jun 2007 03:32:50 +0200

[Vladimir Prus (vladimir-prus)]

I am afraid this fix breaks things for me. I have a M-Audio Keystation 61es MIDI keyboard, and I connected it directly to timidity using kaconnect. Then, I have experienced a serious lag between pressing a key, and hearing a sound -- enough of a lag to make playing anything impossible. When I put back -B2,8 options, things went back to normal.

So, it seems that some further analysis and fix is needed here. What is "slow and noisy" in the original report? I'd imagine that 2,8 options might be too aggressive. I used to have 8,64 some time ago (with fluidsynth, so the interpretation of those values might be slightly different), and it worked fine everywhere.