The Speex sample rate converter has problems it appears and consumes and inordinate amount of CPU upwards of 57% when converting from 44.1 to 48 and it still sounds bad. Even with the Audacity generated 300Hz tone at 44.1 the quality does not improve. If I suspend PulseAudio 4.0 and play with straight ALSA, all of the problematic wave files at 44.1 play beautifully with little burden on the CPU. I have tried the 'tsched=0' recommendation on the udev module load line and still get the same poor quality. I use PulseAudio primarily for echo cancellation during video conferencing for which it performs beautifully. Is there a way to bypass the mixing/resampling in PulseAudio and let ALSA perform these functions? On Tue, Jun 25, 2013 at 12:03 AM, Robert Krakora < rob.krakora at messagenetsystems.com> wrote: > Hi Peter, > > If I convert all four files, which sent you, to 48K then they all play > fine via PulseAudio 4.0 (no motor boating). The frequency spectrum of the > 300Hz tone at 44.1K looked a lot different from the 300Hz tone generated by > Audacity at 44.1K. I agree that the tone is not perfect. However, the > other three files also play poorly on PulseAudio 4.0, but play fine on ALSA > 1.0.25. > > Best Regards, > > Rob > > > > On Mon, Jun 24, 2013 at 8:26 PM, Robert Krakora < > rob.krakora at messagenetsystems.com> wrote: > >> Hi Peter, >> >> Thanks, I suspect the resampling as well. I will take a look at the wave >> file with audacity and generate a pure 300 Hz tone. Thank you for your >> time. >> >> Best Regards, >> >> Rob >> >> >> On Mon, Jun 24, 2013 at 7:23 PM, Peter Meerwald <pmeerw at pmeerw.net>wrote: >> >>> >>> > I just provided the files to you via YouSendIt. You should be >>> receiving an >>> > e-mail with a link to them. Thanks in advance for your help. >>> >>> the mysterious 300HZ.wav is not a pure 300Hz tone; >>> it plays distorted (on ALSA and PA) because the signal is distorted >>> >>> when you look at it in Audacity (Analyze -> Plot Spectrum) you see plenty >>> of frequency components besides 300Hz; you can generate a pure 300Hz tone >>> using Generate -> Tone and compare >>> >>> I do not know why ALSA and PA sounds differently for you, it might be >>> resampling >>> >>> regards, p. >>> >>> -- >>> >>> Peter Meerwald >>> +43-664-2444418 (mobile) >>> >> >> >> >> -- >> Rob Krakora >> MessageNet Systems >> 101 East Carmel Dr. Suite 105 >> Carmel, IN 46032 >> (317)566-1677 Ext 212 >> (317)663-0808 Fax >> > > > > -- > Rob Krakora > MessageNet Systems > 101 East Carmel Dr. Suite 105 > Carmel, IN 46032 > (317)566-1677 Ext 212 > (317)663-0808 Fax > -- Rob Krakora MessageNet Systems 101 East Carmel Dr. Suite 105 Carmel, IN 46032 (317)566-1677 Ext 212 (317)663-0808 Fax -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.freedesktop.org/archives/pulseaudio-discuss/attachments/20130625/a3330a32/attachment.html>
