On 22/10/14 04:15, Len Ovens wrote:
On Tue, 21 Oct 2014, Harry van Haaren wrote:
Hey all,
I have a HDA ( cat /proc/interrupts tells me so anyway:
snd_hda_intel ).
Its my built-in laptop soundcard, and it works pretty well, down
to about 44.1kHz, -p128
-n3. That's ~8ms, which is acceptable IMO.
I've read on mailing list / internet somewhere* that spec for
the HDA is pretty
open-to-interpretation, so I think the exact hardware / chipset
would need to be tested
to get true results.
This is also what I was lead to believe. snd_hda_intel covers a fair
range of different chips, each of which has its own characteristics
and so there is no single answer to the original question. Pretty
sure both my last two laptops were reported as snd_hda_intel and
know they were definitely different sound chips! (Although offhand
couldn't tell you what...)
"Like AC'97, HD Audio is a specification that defines the
architecture, link frame format, and programming interfaces used by
the controller on the PCI bus and by the codec on the other
side of the link. Implementations of the host controller are
available from at least Intel,
Nvidia,
and AMD."
[1]
I have gotten 48k -p64 -n3 on mine. Jack will crash if
I try -p64 -n2, but -p128 -n2 works.
From my reading, HDA is (like AC97) more of a bus spec than a
sound spec. It seems to deal with connecting the sound from the HW
to the internal bus. The HDA bus runs at 48K (like AC97) but does
not expect the HW to be 48k (as AC97 did) and has methods for
transporting audio with other sample rates than 48K.
In my opinion, 128/2 is just on the edge of useful for live
(guitarix for example) use. 256/2 is annoying already. (No I do
not play play really fast or anything like that)
With no careful tuning I run my internal at 48k -p128 -n3 and get
rare xruns, mostly if I have my wifi turned on but still the very
occasional one otherwise.
Not sure if there is a mistake on the page or if my laptop actually
has both of these for something?? [2]
Intel
7 Series/C210 Series Chipset Family High Definition Audio
Controller
Intel
Panther Point High Definition Audio Controller
[1] http://en.wikipedia.org/wiki/Intel_High_Definition_Audio
[2]
http://www.ubuntu.com/certification/hardware/201206-11273/components/