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Capturing Multi-Track Raw Audio?
afex asks: "I've been in and out of bands, and my current one is ready to sit down and put out a nice sounding Promo CD. In the past, I've used a horrible mess of equipment to get this job done. I won't go into detail on what all the microphones were for, but I had 4 going into an analog mixer, mixed down to 2 channels - as well as four other microphones that were unmixed. This left me with 6 separate tracks, which I am now outgrowing. I'd now like to start capturing 8 (or more) channels of raw (delivered via XLR cables from mics) audio. As for quality: 44.1K/16bit is fine. The editing can be done later via software, but my main quest is to get a single piece of hardware (either for my PC or a standalone box) that will ONLY capture the audio - no EQ's, no FX, no mixing, nothing, since that is all done later, on the PC. Got any ideas, Slashdot?"
"I used to record it all using 2 stereo USB capture devices (Edirol UA-1A & M-Audio MobilePre USB), as well as the PC's soundcard (left and right). I recorded and mixed with Cool Edit Pro, which is now Adobe Audition. This method has been very buggy, and its time for a change. I don't want to add more USB/FireWire capture cards to the mix, and I don't want to pay a heap for a digital 8-track recorder such as Yamaha's AW16G. What can I do?"
They both make good multichannel audio interfaces at a good value for the price. I've gone with Echo Audio in the past, and not been entirely happy with the drivers, stability, and support. Interfaces are available as either PCI cards with connectors/cables, pci cards with a breakout box, or (my recommendation) an external box with firewire connectivity. It's the most flexible, you can position the unit away from the PC to avoid RF interference, and in my experience works at least as well as those with dedicated PCI cards.
It's good to know that other people have had good experiences with MOTU.
Mine has been pretty lackluster. All I can remember is being really pissed off that I had to log-in to their website to download updated drivers. (See for yourself: http://www.motu.com/download/)
If that wasn't bad enough, it took HOURS for the aproval email to arrive in my inbox. Meh.
This is the piece that I just picked up and I can't tell you how happy with it I am so far.
r /products_detail.php?product_id=139
http://210.243.85.5/partner/modules/product_explo
http://www.phonic.com/
The Phonic Helix Firewire 18. It sends the signal pre any EQ or mixer, the only control is the gain. Up to 16 Channels into your computer. Works like a charm, and the price is great for what you are getting. I picked mine up for a little over $500 (Canadian) and it also functions as a standalone mixer.
I'd post a link to some tunes that we've recorded with it, but they are not ready for general consumption yet. You can check out some of our previous stuff at http://www.tractorgrease.com/main/thedirt/
If you buy one good multi-io card you can skip the mixer, skip any extra mic-preamps and drop the extra sound cards. With one card and a suitable recording software you'll get perfect multitrack recording.
Unfortunately only a few audio interfaces support 2 or more mic inputs, but this one from Alesis seems to have 8 http://www.alesis.com/product.php?id=94
Why are you asking a question about digital recording on Slashdot when there are so many better places to ask?
p hp
Just a few links:
http://messageboard.tapeop.com/ (my favorite)
http://recforums.prosoundweb.com/
http://gearslutz.com/
http://acapella.harmony-central.com/forums/index.
A lot of the various sound cards come with an adat interface (or multiple) that you can use, what you need to do is get a preamp, the first one that comes to mind is http://mackie.com/products/800r/index.html this, you can get them cheaper, but with audio gear a lot of times you get what you pay for, and mackie is good stuff, so you get a soundcard (your choice of interface) with many adat inputs, and add preamps as needed
I'm a big fan of ardour; as a software mixing console, it's hard to beat.
But, if you just want to grab raw audio and dump it to file, there may be simpler (and more robust) alternatives.
My own favorite is ecasound. It's pretty light on resources and easily handles any real time recording task. And, it can be run entirely from the command line (and thus from the scripting language of your choice) and has a console client, both of which are convenient if you want to leave it running on a dedicated machine without having to be physically present. (I suppose you could try running ardour through a vnc.)
Ardour doesn't crash much these days, but compared to ecasound or less featurefull alternatives, it's a serious resource hog and a pain to set up if you're just recording raw data.
Yes - the reason for recording at higher sample rates - 96 kHz, and even 192 kHz, is that the anti-aliasing filter (which has to be down 40 dB at the Nyquist frequency - 1/2 the sample rate) can be much gentler. A brick wall filter dropping 40 dB from 20 kHz to 22.05 kHz tends to also be an oscillator near 20 kHz, and it has phase distortion down to around 5 kHz. Instead, running a filter that drops 40 dB from 20 kHz to 48 or even 96 kHz can be a much smoother filter with the phase distortion out of the audible band.
Turn it into a 44.1 kHz CD after mastering.
Well, the Onyx does 16 channels of audio, plus a stereo mix - and a 16 channel ADC box will cost you more than $400, usually, plus you won't get the scratch mix.
Or in the case of this guy's actual question, where he doesn't want to have a mixer at the frontend at all, just go straight into the DAC, I think it's a little bit of overkill. True - but maybe he needs a new mixer anyway. Sounds like it, with all the submixing he has to do.
A question I have though, for you or anybody else who has experience and wants to answer: what format do these FW audio interfaces use for transporting the audio streams over FW? Is there a standard format / specification for transport, like there is for DV? So basically, any multichannel audio interface will work with whatever software you want? Or is it proprietary and you have to get device-specific drivers? And what does the device "look like" to the computer (I use a Mac) ... is it a Core Audio device, or can you only access it from within specific, vendor-suppored applications? (I see Mackie bundles their products with Traction, for example, and I can only assume there's a ProTools plugin.)
On the Mac, it's easy - they have Core Audio drivers, and are usable by any well-written Mac application (YMMV with ProTools). But in Garageband, Nuendo, Final Cut, Audacity, etc., they just show up as regular input/output devices. Neat thing with Core Audio is that you can actually route one interface to multiple programs simultaneously (send inputs 1-6 to Garageband, inputs 7-8 are the mix through an outboard piece of gear then brought back to Nuendo, use inputs 9-16 for tape ins in Audacity).
Not that you'd ever want to do something like that, but you can.
On the PC, after you install the hardware, reboot, install the drivers, reboot, re-install the hardware and reboot, they show up as a multimedia I/O device, and should be selectable in most programs. Again, ProTools might not see it, because they write for their own proprietary interfaces and don't like to play with the other kids.