[linux-audio-user] Just how bad is USB audio?

-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 Hello, I'm considering buying a USB sound card for my laptop. (I have no desktop box worth talking about atm.) Everyone says a USB card is a Bad Thing, but I've found few numerical measures, and I don't have much of a choice anyway (unless someone releases a firewire card, or a pcmcica one under $1000)... If someone can point me to some more concrete data, it would help me make my choice. (Which is basically to buy or to suffer crappy sound, as I see no real alternative...) CPU utilization is the main problem. I probably wouldn't count as a hardcore gamer, since I have a p3-900 with 256mb ram and it's enough to run all the games I need (mostly ps1 emulations, but some sims/fpss too). So what performance hit should I expect from using a usb audio device? The only review on the net that actually mentioned numbers was one of the Extigy on Tom's H/w Giude, and it said 20% cpu of a p4-2Ghz, but that was using 6 or 8 channels with special effects requested by something on the order of UT2003, which is out of my league anyway. I don't have or plan to have any other high-bandwith devices on my usb (1.1) bus, just a keyboard/mouse/joystick. Also I only have 2 speakers atm, so I'll only be streaming two channels. Therefore bandwith shouldn't be a problem as I understand it. OTOH I'd want to do some none-cpu-intensive work (writing, reading) while listening to mp3s and copmpiling stuff in the backgruond. I would probably accept some slowdown in the compiling, as long as the audio didn't skip and responsiveness wasn't affected (I already use a kernel with all the low latency/preempt/O1 scheduler etc. patches and have a prelinked system because I really hate responsiveness issues)... Finally as to the card itself: AFAICS there are the costly ones (Extigy and Audiotrak Maya 5.1 usb), which have lots and lts of features most of which I don't really need, and some cheap ones like the iMic or Xitel Hi-Fi-Link which only have stereo rca input/output. The latter type is much closer to what I'd be using of all those features, but unfortunately I cannot find them in any shops here in Israel, and if I order over the internet I'll have to pay for shipping and won't have warranty coverage. So I'd be willing to pay for the maya card if I cuold be sure I'll be using it well, preferrably also when I build my next desktop system in a year from now. Any recommendations, info etc. will be most welcome :-) - -- Dan Armak Matan, Israel Public GPG key: http://www.gentoo.org/~danarmak/danarmak-gpg-public.key