[LAU] Re : lowest usable latency from a USB 1 device?

[Jeremy Jongepier]

On 09/17/2011 08:14 AM, Frank Kober wrote:
>
>
>
>
> ----- Mail original -----
>> De : Paul Davis<paul at linuxaudiosystems.com>
>> À : linux-audio-user<linux-audio-user at lists.linuxaudio.org>
>> Cc :
>> Envoyé le : Vendredi 16 Septembre 2011 19h33
>> Objet : [LAU] lowest usable latency from a USB 1 device?
>>
>> if you can run a USB 1 class compliant audio device on your linux
>> system with lower latency than the current minimum so far posted to
>> this thread, please post with the settings you use and the type of
>> device. if your best performance has already been posted, no need to
>> repeat it.
>>
>> i'll get the ball rolling with 2048 frames. note that we are assuming
>> 2 channels only, but duplex mode (simultaneous capture+playback).
>>
>> thanks.
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>> Linux-audio-user at lists.linuxaudio.org
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>>
>
> As some others here:
>
> Edirol UA-25 with
> nperiods 3, frame size 128, 2x2 (duplex) 48kHz
> without any problems on a 2.6.33.6-1.rt26 kernel and some sporadic xruns on a 3.1.0-rc5

Same device here, Edirol UA-25. Lowest possible latency I can achieve is 
2ms (48 frames/period, 48 Khz sample rate and 2 periods/buffer) but that 
isn't very usable. It runs in a pretty stable manner at 64/48000*3 (4ms) 
but just to be sure I mostly use 128 frames/period.

Best,

Jeremy