On Mon, Aug 02, 2010 at 02:10:56PM +0200, Remco wrote: > I was looking at the Alesis iO|2 USB audio interface. It seems like a nice > device, especially since it appears to comply to both the USB-audio as well > as the USB-MIDI standard, see: > http://www.linuxquestions.org/ > questions/linux-hardware-18/2-soundcards-alesis-io|2-and-nvidia-ck804-512025/ > > However, it appears to limit audio to 24-bits @ 44.1/48kHz. > > To my understanding, applications accessing this device through libsndio will > use its native resolution. For applications requiring 16-bit audio I could > run > an aucat server on top of this device. > > According to BUGS in aucat(1), aucat uses 16-bit processing. Does that mean > that aucat will always record/playback only the 16 most significant bits for > resolutions > 16 bit (always limiting the dynamic range) ? > > Apart from limiting the dynamic range, I was wondering if a pure 24-bit > device > could potentially be troublesome in any way. e.g. will running an aucat > server in 16-bit mode add any kind of additional distortion or noise, or can > i expect it to behave as a device doing 16-bits @ 44.1/48kHz ? > Will applications work without issues ?
I believe mplayer should work at 24 bits with a 24-bit uaudio. I don't recall if I tried that or not. yes, not many applications support 24-bit audio, so you'll need aucat for "general use". works fine for me. note: if you have an azalia you might be able to make it use 24-bit in the hardware to get an idea. there may be some applications/libraries that could support 24-bit but don't. perhaps there are some ports that could support 24-bit formats but don't. gstreamer comes to mind. 24-bit support wasn't really a priority when I did the sndio backends. until a few weeks ago 24-bit support assumed a 4-byte sample size ... -- jake...@sdf.lonestar.org SDF Public Access UNIX System - http://sdf.lonestar.org
