Re: [Jack-Devel] Can't bring F/P below 128

On 12/31/2011 06:43 PM, Adrian Knoth wrote:
> On Sat, Dec 31, 2011 at 01:51:31PM +0200, Nikos Chantziaras wrote:
>
>>>> It's about the on-board sound chip being quite lame latency-wise, while
>>>> a cheap-ass, ancient PCI card I have lying around unexpectedly turns out
>>>> to be quite the low-latency monster.
>>> Are you really surprised by that?
>
> I would. There are rumors some (onboard) HDAs can do eight samples per
> buffer. I have no idea if this is true, but I can confirm 2x32 on a
> couple of motherboards I have around. That's 0.7ms at 48kHz.
> [...]
> I still wonder if there's anything wrong with your setup, because I've
> been playing synthesizers at 12ms for years, including fast rock'n'roll
> piano repetitions.

I just discovered something that is probably worth mentioning.  In LMMS, 
there's an additional setting that affects latency: "Buffer size".  I 
wrongly thought that this settings only affects the ALSA backend.  It 
was set to 512 frames (11.6ms).  I assumed this was a setting that told 
LMMS how to open the ALSA device (hw:0) and that it had no effect when 
using the JACK backend.

I assumed wrong.  It's weird that I didn't figure this out a lot sooner 
(I remember playing around with this setting.)  But this *does* have an 
effect even when using JACK.  So I was adding 11.6ms to my total latency 
and didn't even know it :-P  So I turned that down to its minimum 
setting (64 frames, 1.5ms) and now I indeed can't tell the difference 
between 2.67ms and 5.33ms (or even 10.7ms) in JACK.

That was quite stupid of me.  Fortunately, getting the new soundcard 
wasn't a total waste of money; it's better in video games than the 
onboard sound (Dolby Headphone actually works :-P)  (It's also 
*supposed* to have better sound quality, but I don't know about that; 
never bothered to ABX it.)

1326228739.22308_0.ltw:2,a <jei8d3$lpo$1 at dough dot gmane dot org>