Hmm, I've got my hands somewhat dirty with this, although not from a particularly Linux-friendly viewpoint. My requirement was/is a four channel card for use with Ambisonic recording and a laptop (and ideally with my current desktop too). Stages I've been through:
1. M-Audio Quattro (USB): Got excited for the first time. Bought one. Didn't work. Apparently the early ones with "Mac version" on the box really mean it - it's not just a driver issue. While talking to support folk etc it emerged that the card is high latency (I don't have numbers), though they were hoping to fix this to an extent. Further, it turns out that 4x16x44.1 is about the limit that USB can take - you can't do 4x24x44.1 for instance, simply because USB doesn't have the bandwidth. Also, I couldn't find any hint of a decent recording level control for use in ASIO mode (bad with only 16bit) although to be fair I never had the thing working properly. Took it back. 2. MOTU Firewire thing: Got fed up and eventually foolish enough to go for this. Did some research and it seemed that although this card is "firewire compatible", it only really works with Macs. Possibly with some firewire cards on some PCs/laptops, but not all and getting hold of this information proved difficult. And the card is *expensive*! Eventually got disheartened and decided that until this was all cleared up I'd just buy a cheap four-input card for my desktop to tide me over and forget the laptop. Then I found... 3. Echo/Event Layla/Mona: These PCI cards have been around for a while. I've just bought a Mona. This has four inputs with preamps/phantom power, six outputs, and a host of digital ins/outs. The Layla is even better (although I don't think it has the preamps/phantom power). I talk to the Mona through ASIO although I found an incompatibility/bug in Steinberg's ASIO SDK - luckily this comes in source form so it's fixable. Comments: the digital engineering seems very poor - this "plug and play" card had an IRQ conflict with my existing audio card, an old Gina by... Echo/Event. This resulted in all sorts of odd Windoze crashes, mostly resulting in bluescreen. It seems that neither of their cards bother to do the plug and play "negotiate" thing. Problem was fixed eventually by moving the cards to different slots on the motherboard (eek). The Mona "monitor" program (will the volume sliders/monitors) is of a far lower grade than the one for my Gina card and the graphical volume monitors on the rack and the software do some odd things when both playing and recording. Apparently this is a temporary program while they develop a Java version, though the idea of running a JVM within a single CPU box doing low-latency audio fills me with dread. Luckily you can switch the monitor program off without breaking anything (apparently). Having said this, now that I've dealt with these issues the card is working very nicely! And why did I go for this card in the first place? Because they've just brought out a PCMCIA card that talks to the external breakout box (where the A/D/A converters are). I've not seen this yet and I have an instinctive distrust now for the quality of the control logic involved, but I'm trusting that this can be made to work! I'm not aware of any likelihood of *any* of these cards (or my old Gina) being supported on Linux any time soon, although few technical teams I've spoken to don't seem unfriendly - it seems more a matter of resource. Comments from ALSA/OSS folk appreciated... --Richard > -----Original Message----- > From: [EMAIL PROTECTED] > [mailto:[EMAIL PROTECTED]]On Behalf Of Brad > Bowman > Sent: 18 January 2002 03:16 > To: linux-audio-dev > Subject: [linux-audio-dev] USB Souncards > > > I was planning to get a new sound card to use now > with my current fragile laptop and future whizz-bang > desktop. As they only have USB in common I thought > that might be best although hints in the earlier > usb audio thread have worried me. If I'm paying > a premium price for poor performance then I might > just wait until I'm in a position to get a nice > desktop. > > So, in short, what are the issues with USB sound cards > under Linux? In particular, does it effect latency and > realtime reliability? [...]
