[CM] New to SND

Kjetil Svalastog Matheussen k.s.matheussen@notam02.no
Thu, 30 Dec 2004 16:19:54 +0100 (CET)


Pam & Harold Norris:
> 
> Hi,
> 
> My interest in snd is realtime recording of our church service with 
> editing afterwards.  I know I can do this with arecord as well as a 
> couple of others, but liked the looks of snd, especially the VU meters.  
> HOWEVER, I need 8 channels in AND out.  I have made some progress in 
> achieving this but it seems like an uphill battle.  I am using version 
> 7.8 and snd_conffile.scm.  I have gotten as far as the 8 channels in but 
> haven't gotten 8 channels out to disk.
> 
> Is snd the right software to use?   Are there instructions somewhere 
> which will tell me how to do this?
> 

I don't think you should use snd_conffile.scm when playing 8 channels I'm
afraid to tell.

The file does some scheme things while playing which cause regular garbage
collections. Clicks can be avoided by setting a very very large dac-size, 
but 8 channels is quite much...

Or you should be able to avoid it totally by removing the following lines 
from snd_conffile.scm :

;; Show the time in the minibuffer when playing
(let ((samplecount 0))
  (add-hook! play-hook
	     (lambda (samples)
	       (set! samplecount (+ samplecount (* 40 samples)))
	       (if (> samplecount (srate (selected-sound)))
		   (begin
		     (set! samplecount 0)
		     (c-show-times (cursor) #f)))
	       #f)))



Anyway, snd only use one thread for all its work, which currently 
sometime isn't very nice for realtime work. So perhaps you should
looking at ecasound or ardour instead...


--