[Top][All Lists]
[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: [fluid-dev] Delay and buffer size
From: |
Z F |
Subject: |
Re: [fluid-dev] Delay and buffer size |
Date: |
Tue, 24 Oct 2006 13:56:59 -0700 (PDT) |
Dear Josh Green
Thank you very much for your thorough explanations.
I did put "-o audio.alsa.device=hw:0" option to make fluidsynth
consume 10% instead of 100% of CPU.
Thanks again
ZF
--- Josh Green <address@hidden> wrote:
> On Thu, 2006-10-12 at 19:41 -0700, Z F wrote:
> > Hello everybody,
> >
> > I have read in the list archives that if there is noise while
> switching
> > windows, than the buffers and the number of them needs to be
> increased.
> > this will, however, will increase the delay in responce.
> > On my system I had to do fluidsynth -c 16 -z 1024 to get rid of the
> > noise. The question is than is, what is the delay in ms(?) compared
> to
> > the default. And also, what kind of delay will not be noticable?
> >
> > Thanks for your help
> >
> > ZF
> >
>
> Hello.
>
> It depends on what sampling rate you are running at. But if you are
> running at 44100 then you should calculate the delay like so:
>
> (16 * 1024) / 44100 = ~372 Milliseconds
>
> For live work, that would likely be very noticeable latency. You can
> likely get better latency (with little or no artifacts) by running
> FluidSynth as root. There is currently the danger of machine lockup
> though, if all CPU is consumed. This can be limited by setting the
> maximum number of allowable voices. There may be latency issues with
> the kernel you are running too. That's an art in itself though, in
> getting a good low latency kernel. Some kernel versions in 2.6 are
> rather bad, others are better.
>
> One other thing to try is make sure you are using the ALSA hardware
> device rather than the plugin system. This can be done by passing
> the
> following switches to FluidSynth "-o audio.alsa.device=hw:0".
>
> Max number of voices can be set with: "-o synth.polyphony 64". That
> will set the max number of voices to 64. You may want to try
> something
> lower perhaps first when running as root to make sure all your CPU
> isn't
> consumed when all voices are used (a very good possibility when
> playing
> MIDI files).
>
> There is likely a lot that could be done coding wise with FluidSynth
> to
> improve things, in this regard. Not sure when I will get around to
> it
> though.
> Josh Green
>
>
>
__________________________________________________
Do You Yahoo!?
Tired of spam? Yahoo! Mail has the best spam protection around
http://mail.yahoo.com