usb, firewire and latency

[funkmuscle]

hey guys,

I wanna pick up an external soundcard module and was wondering if to go with usb or firewire and what are the issues with them like latency, xruns etc...

also, I wanna know which is recommended...

[autostatic]

Go Firewire and get yourself a Focusrite.

But how many channels do you need? And the quality of the recordings and playback?
And issues concerning latency and xruns are mostly related to the system configuration, Firewire controller or other factors (CPU, GPU, memory, disk speed etc.).

[funkmuscle]

AutoStatic, thanx... I figured you would the first to answer as I was reading something from you on here:

http://www.linuxquestions.org/questions ... ht-617893/

not too many as I'm an apartment... I just to plug in a mic and direct recording for my guitar..

[autostatic]

Ah, then the aforementioned Edirol UA-25 might be a good option. It's follow-up, the UA-25EX, performs well too.
Funny to read that thread again, I was using the wrong Periods setting and that was still on my old laptop that was as crappy as hell.

[funkmuscle]

yeah, my laptop has a snd-hda-intel and I can't get jack to run... xruns are so bad that it shuts off jack.
so if I can't get that fixed, I'm looking for an external interface..

[Capoeira]

i wouldn't restrict to firewire if its for 2-channel. Including usb-devices gives you more options. If you want more than 2 chanels go firewire

[funkmuscle]

so you get more channels with usb???

[Capoeira]

so you get more channels with usb???

no,

I said USB is kind of restricted up to 2-channels because of bitrate. USB2 can handel more channels but i heard Firewire is better for that. But if its for 2 channels you can go even USB1

[funkmuscle]

ok, I see... firewire for me then....

[autostatic]

FireWire is way better for audio. It allows for bigger simultaneous data streams contrary to USB, USB can only send or receive at once. And yes, USB1 is kind of restricted to 2 channels, there are devices with more channels (like the Lexicon Omega iirc) but those are a pita to set up and I wonder if they will ever work at full-duplex with 4 channels. And USB2 seems nice, but the major drawback is of course the very limited number of supported cards because there is no USB2 audio standard (like there is for USB1).

[Capoeira]

FireWire is way better for audio. It allows for bigger simultaneous data streams contrary to USB, USB can only send or receive at once. And yes, USB1 is kind of restricted to 2 channels, there are devices with more channels (like the Lexicon Omega iirc) but those are a pita to set up and I wonder if they will ever work at full-duplex with 4 channels. And USB2 seems nice, but the major drawback is of course the very limited number of supported cards because there is no USB2 audio standard (like there is for USB1).

yea, and other thing is that you will have other USB-devices conected wich will share the USB-controler with the card. But for 2 chanels and with rtirq its perfectly usable. Only mentioning this for people with restricted budget. For example, I got my M-Audio-duo from 2002 (I think) verrrry cheap and I can record with it even with 2,9 ms of latancy. http://www.zzounds.com/item--MDODUO. And new usb-devices are cheaper, too

[autostatic]

For example, I got my M-Audio-duo from 2002 (I think) verrrry cheap and I can record with it even with 2,9 ms of latancy.

Did you ever try to run it with a latency of 2ms ?

But don't forget about the quality of the preamps and A/D-D/A convertors too. That's normally better with FireWire cards. I can really discern a difference in quality between my Edirol UA-25 USB card and my Focusrite FireWire card.

[Capoeira]

For example, I got my M-Audio-duo from 2002 (I think) verrrry cheap and I can record with it even with 2,9 ms of latancy.

Did you ever try to run it with a latency of 2ms ?

eheh, that realy doesn't make any diference you have 3ms of latancy for the time the sonic needs to reach your ears from your monitors (in 1m distance). I doubt you can here that

But don't forget about the quality of the preamps and A/D-D/A convertors too. That's normally better with FireWire cards. I can really discern a difference in quality between my Edirol UA-25 USB card and my Focusrite FireWire card.

correct, preamp and converter quality is critical and sure at this segment you get what you pay.

[autostatic]

eheh, that realy doesn't make any diference you have 3ms of latancy for the time the sonic needs to reach your ears from your monitors (in 1m distance). I doubt you can here that

I know, but it's just fun to try out, to see if it works, but it has no real practical use. Afaik 2 ms is the lowest possible latency one can achieve with USB.

[Capoeira]

eheh, that realy doesn't make any diference you have 3ms of latancy for the time the sonic needs to reach your ears from your monitors (in 1m distance). I doubt you can here that

I know, but it's just fun to try out, to see if it works, but it has no real practical use. Afaik 2 ms is the lowest possible latency one can achieve with USB.

If I go with 32 frames/period and 3 period/buffer jack wont even start. 2,9 ms is minimum for me