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Installing/Configuring ALSA Sound Modules In Debian
GonzoJohn writes "Linux Orbit explains how: "A very common question that comes up when trying Debian GNU/Linux is how the heck do you get Advanced Linux Sound Architecture (a.k.a. ALSA) sound modules set up properly? In this HOWTO we'll show you how to compile and install the ALSA kernel modules, and then setup things using the ALSA Debian script so that modules are automatically loaded and unloaded, and your mixer levels are saved and restored on boot up. Here are some things you'll need to have before you start this HOWTO""
Gentoo Linux has had a similar guide for months, without coverage on the front page of Slashdot. (And, if I may say so, the Gentoo way is cleaner.)
Maybe I'm missing something, but why/how is this news?
Umm... this how-to appears to be very well written, in fact much better written then the lack of documentation that comes with the package, the last time i setup ALSA it took me about 48 hours mainly because no where was it clearly explained how to do things, it was read as much documentation as you can and try to make up the manual yourself based on what you know from the API. Essentially this how-to is now the manual
It has ALSA built in.
Compiling your own kernel additions is for experimental stuff, not stuff that has been working for years like ALSA
If you're really quite serious about A/D quality, look into using an external box for the task. Midiman makes a couple of different, well-performing 24-bit models, and they occasionally pop up on Ebay. Or, you could pick up a nice pawnshop/Ebay DAT or Minidisc deck, and use that.
Not that you need 24 bits to transcribe vinyl, but it does help ensure that you'll not run out of headroom. Later in the process, you can normalize the audio and truncate or dither it down to 16, while preserving every nuance of the album's pops, ticks, and surface hiss.
Plug a box like this into a sound card's SP/DIF input. The stupider, cheaper, more DSP-phobic cards will generally be more likely to do a bit-perfect job of this, such as the $12 Zoltrix Nighingale or other CMI8738-based cards. Along the same lines, do try to avoid anything branded Creative Labs, mmkay? They've got bad habits like irrevocable resampling, and are noisy throughout (even when only doing strictly "digital" things with SP/DIF IO).
That said:
I used to play engineer for a streamed talk radio show. Equipment was limited to the gear in a small project recording studio, none of which was intended for broadcast use, aside from the scrap-built Linux box running liveice and lame.
Since this box needed a sound card, I drove over to the nearest white-box OEM parts dealer and started looking. I picked a YMF744-based (XG) PCI card from AOpen, similar to this one, based primarily on the component count: It was the only card under $50 which was not branded Creative, and appeared to have reasonable analog filter stages and signal paths.
It turns out that this card, along with other Yamaha XG cards, has superb support under ALSA, and that the quality of the converters is not bad.
The control of the card was such that I was able to calibrate it to the output meters on the Tascam console, and monitor the program via digital loopback through its own DAC at 0 gain.
I could then push a button on the console, and switch between monitoring the signal in its original analog state, or after it'd been through a ADC->DAC stage without worrying that varying levels would skew my perception.
In the (somewhat noisy) enviroment I was in, I could hear no difference in overall quality with or without the Aopen card in-line. This cheap sound card was, in a word, transparent, at least for my purposes. Which is all I can ask of any sound card.
ALSA made this easy, but I suspect I'd have trouble doing things so precisely under other operating systems.
But I've noticed that not all XG-based cards are made the same. Hoontech sells, or at least sold a year or two ago, some expensive studio-oriented monstrosities which doubtless sound beautiful. On the other end of things, I've heard some laptops with XG chips which sounded horrible.
Lately, I've been recording my 2-year-old daughter's various noises with an SB Live 5.1. The results are OK, but nothing like what I remember hearing in the studio. I could blame the card's on-board mic preamp or the sound of my apartment, but I fear that shoddy AD plays at least as large a role in the matter.
Good luck.
Kid-proof tablet..