Ardour - changing sample frequency

  • johne53
Posted: Thu, 10/18/2007 - 15:39
I have Ardour running on my desktop PC (under OpenSuse 10.2). I can change Ardour's sample frequency (e.g. from 48K to 44.1K) by launching QJackCtl and changing the sample rate (usually, just before I launch Ardour). My laptop PC is running 64studio - but its version of Ardour seems to be stuck at 48KHz. Even if I select 44.1K in QJackCtl, I still get Ardour running at 48K. Is this correctable?

Its no a Linux problem at

  • davidpucheta
  • 07/26/07
  • Fri, 10/19/2007 - 05:14
Its no a Linux problem at all.You can play and record 44.1k stuff with alsa or oss (try playing any wav file @ 44.1 and youll see it will play fine with any media player) Im not very sure but i think it is that the internal clock of the thing only runs natively in 48k and plays back 44.1k and others SRs in windows, oss and alsa by doing some kind of resampling, appearently jack doesnt likes this. Once i was having trouble because of this cause i had an Ardour session at 44.1k, then tried to do a mix on the go and surprise no 44.1 on my internal card. Theres a script for converting the sample rate of the whole ardour sessions files at once but although i've been using linux for many years now i couldnt make the script work. Saludos

Yes, I'm using the inbuilt

  • johne53
  • 10/07/07
  • Fri, 10/19/2007 - 04:47
Yes, I'm using the inbuilt hardware which is described as "Toshiba AC-XG Audio Device" so I guess it's probably an AC-97 chip. I don't understand what you mean though by "real 44.1KHz". Google has several reports - some saying AC97 doesn't support 44.1K and others suggesting it supports 44.1K but not 48K!!. However, they mostly seem to be anecdotal. I also found reports about Jack not supporting 44.1K with AC97 hardware. To be honest, it's all very confusing. Windows (on the same machine) has no problem playing things at either 48K or 44.1K and it seems to be playing them at the right speed. Do you think this is only a problem in Linux?

What audio hardware are you

  • davidpucheta
  • 07/26/07
  • Fri, 10/19/2007 - 00:26
What audio hardware are you using? If you are using the laptop's built in sound device, good chances are it is an AC 97 chip which is known for not supporting real 44.1Khz. And then Jack jumps up to the next available sample rate.