Re: [fluid-dev] qsynth 0.3.6 for mac osx

[Pedro Lopez-Cabanillas]

On Thursday 14 April 2011, Sven Meier wrote:
> Hi,
> 
>  > The other Mac users on this list are also urged to report their
>  > experiences :-)
> 
> here's my report:
> 
> Fluidsynth starts and is loading the Soundfont correctly. Connecting 
> VMPK with Fluidsynth, the Midi indicator flashes and the messages dialog 
> is filled with fluidsynth:noteoff/fluidsynth:noteon confirmations.
> 
> But
> - no sound, no activity on the peak level meter either.
> - after a while playing the virtual keyboard the messages dialog is
> flooded with event_pre_noteoff/event_post_noteoff messages,
> - then the following messages appears for each key press:
>    fluidsynth: warning: Failed to allocate a synthesis process
> 
> My own build of Fluidsynth is working flawlessly on my machine.

Has your Mac an Intel or a PowerPC processor?

One of the changes of the new coreaudio driver in post-1.1.3 is that you can 
set the audio buffer sizes. The old driver had some fixed value selected by the 
system. It is calculated now as the product of the buffer size (-z) multiplied 
by the buffers count (-c). The defaults in Fluidsynth are 64x16 (=1024) which 
is fine, but qsynth has 64x2 (=128) as defaults, which may be fine for the Jack 
driver but too small for this new coreaudio driver, and may produce silent 
output (also depends on the audio hardware, of course). Try with larger values 
like 256x2 (=512). 

This setting needs to be fixed in qsynth for Mac OSX, even if it isn't the 
cause of your problem.

Regards,
Pedro