ZynAddSubFX was: Re: [linux-audio-dev] some new soundfiles on-line

Benno Senoner sbenno at gardena.net
Sat May 14 10:25:07 UTC 2005

Florian's pratical experience confirms what I stated in my other message.
My take on the matter is to get a good soundcard with fast DAC/ADC ( 
2msec round trip AFAIK)
and use something like 64frames latency. 64 frames gives you still 
good,reliable  RT performance and does not
push the kernel to the limits nor does the setup part of DSP of dsp 
algorithms get bigger than the
actual audio rendering.

eg in a sampler you don't have only to render the audio samples but 
check for note events, ramping,
calculate filter coefficients etc which all take some time which could 
be bigger than rendering the audio
of N samples for N a very small number (eg N < 4).


Florian Schmidt wrote:

>On Fri, 13 May 2005 17:02:42 -0400
>Lee Revell <rlrevell at joe-job.com> wrote:
>>>paul knows that zyn is not RT-safe. he had several conversations with
>>>me at LAC2005 about how to redesign the internals. it works fine at
>>>larger latencies.
>>Judging from those messages, it seems like it should certainly work at
>>128 frames, maybe 64.  But 32 is insanely low - too low for most sound
>>hardware.  That setting is more appropriate for stress testing the
>>kernel, than for actual music making.
>I beg to differ. Especially because some AD/DA's introduce quite a bit
>of additional latency. When i used my cs46xx based card i had to go down
>to 32 frames to get an acceptable latency for playing my guitar through
>jack-rack. I once measured the roundtrip latency of this card and found
>out my AD/DA's added another 4-5ms of latency to the 1.333ms latency
>which were caused by the periodsize of 32 frames. And it seems 6ms total
>latency was fine for me :)

More information about the Linux-audio-dev mailing list