Re: [fluid-dev] MIDI stutters when I move windows

[Menteco]

Florian Schmidt wrote:

> On Thu, 20 Nov 2003 14:10:37 -0300
> Menteco <address@hidden> wrote:
>
>  
>
> > Hi, I am experiencing MIDI output stuttering when I move windows and 
> > sometimes the mouse too.
> > I play the MIDI file with KMid. First I run fluidsynth as:
> > fluidsynth -m alsa_seq 8MBGMSFX.SF2
> > then I run KMid and set it to use fluidsynth.
> > I am using Gnome 2.4 on Debian unstable. The stutter occurs while
> > using Metacity or Sawfish as window managers.
> > My soundcard module is emu10k1 (soundblaster Live!) compiled into the 
> > kernel 2.6.0-test9.
> > Is there a way to avoid this?
> > Cheers,
> > Paul www.menteco.tk
> >    
>
> Yes, either run fluidsynth as root, or:
>
> 1] get a lowlatency [andrews patches. i don't know if they are included
> with 2.6 but i think only the preemt patches are in] and capabilities
> patched kernel, compile and install it..
> 2] install jack
> 3] compile fluidsynth with jack support
> 4] start jack via jackstart [so it aquires RT privs] but as normal user
> 5] start fluidsynth as normal user
> 6] have stutterfree fun!
>
> Works like a charm here..
>
> Flo
>  
I followed your directions and more (see below) but I still experience 
the same degree of stutter (should I call this xruns or clips?) when I 
move windows.
I started jack as: jackstart --realtime --driver=alsa
then I started fluidsynth as: fluidsynth -m alsa_seq 8MBGMSFX.SF2
then I played the MIDI file with KMid.
I read the manpage for jackd and there are too many variables to tweak. 
Any suggestions about tweaking jack's or alsa's buffers, periods, etc to 
reduce clicks?
I am using a Soundblaster Live! card.

My complete installation log of jack and friends is next:
//enable capabilities in kernel source
cd /usr/local/src/linux/include/linux
# gedit capability.h
replace
#define CAP_INIT_EFF_SET to_cap_t(~0&~CAP_TO_MASK(CAP_SETPCAP))
with
#define CAP_INIT_EFF_SET to_cap_t(~0)
replace
#define CAP_INIT_INH_SET to_cap_t(0)
with
#define CAP_INIT_INH_SET to_cap_t(~0)
make xconfig
preemptive kernel
enable tmpfs
recompile kernel
// install..
libcap-dev
libfltk1 libfltk1-dev
doxygen doxygen-gui doxygen-doc
// edit fstab before jack installation
# nano /etc/fstab
shmfs /dev/shm shm defaults 0 0
none /tmp/jack tmpfs defaults 0 0
# cd /dev
# mkdir shm
reboot
// install jack
jack-audio-connection-kit-0.90.0.tar.gz from 
http://jackit.sourceforge.net/releases/current/
./configure --enable-capabilities
// make jackstart suid root
# chmod 4755 /usr/local/bin/jackstart
// install audacity - A fast, cross-platform audio editor
audacity
//install playmidi
playmidi
// install alsaplayer
alsaplayer alsaplayer-alsa
// install fluidsynth from source
// set your PATH to find fluidsynth
% cd
nano .bashrc
PATH=~/scripts:/sbin:/usr/local:/usr/local/bin:/usr/local/kde/bin:/usr/X11R6/lib"${PATH}"
relog to gnome
// play a midi file using a soundfont
fluidsynth -m alsa_seq 8MBGMSFX.SF2 [celebrat_d.mid]
open *.mid with KMid and settings/MIDIsetup=Fluid

Cheers,
Paul www.menteco.tk