On Fri, 22 Feb 2008, Florian wrote: > Hi Bill, > > thanks for the replies. Yes, we are doing research on "ultra-low" > latencies with accompanying realtime Linux and realtime software. > With good PCI cards, our test synthesizer can run quite stable at > 8 samples per period (and 2 periods per buffer) at 192KHz. Now > for presentations we need to show that on a laptop... And, btw, > our software synthesizer is running on realtime Java :)
But the laptop is not running realtime linux is it? It has loads of potential latencies and stuff demanding the system's attention-- page swapping, program swapping, etc. So why would you think that it would work on Linux without underruns? If you wnat 1ms latencies, your computer must be feading the beast at least every .1ms with no interruptions longer than 1ms. That is not many samples in your buffer. I have no idea if alsa can be made to work that way. > > Thanks, > Florian > > > > On 2/22/2008 1:48 AM, Bill Unruh wrote: >> On Fri, 22 Feb 2008, Florian wrote: >> >>> Hi, >>> >>> on our IBM/Lenovo T60 laptop, we want higher audio quality than >>> the built-in HD-Audio, especially low latency - in the range of 1 >>> millisecond or lower. >>> >>> Can anyone recommend a PCCard/Cardbus soundcard, or possibly a >>> USB card supported by alsa and which you've been able to run with >>> low latency? >> >> The usb audio maudio transit I have been quite pleased by, esp now that the >> alsa has stabilised for this card. Latency it sseems to me is more a matter >> of the buffer size that is used than anything else. At 1ms you can only >> have at most 20 samples in the buffer. That runs the danger of underruns, >> since something could distract the computer for that length of time. >> >> >>> >>> Thanks, >>> Florian >>> >>> >>> >> > > -- William G. Unruh | Canadian Institute for| Tel: +1(604)822-3273 Physics&Astronomy | Advanced Research | Fax: +1(604)822-5324 UBC, Vancouver,BC | Program in Cosmology | [EMAIL PROTECTED] Canada V6T 1Z1 | and Gravity | www.theory.physics.ubc.ca/ ------------------------------------------------------------------------- This SF.net email is sponsored by: Microsoft Defy all challenges. Microsoft(R) Visual Studio 2008. http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/ _______________________________________________ Alsa-user mailing list Alsa-user@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/alsa-user
