Recording from XLR to computer...need a USB interface?

If you want to get decent quality recordings, you need something a bit more sophisticated than the computer line in. USB interfaces are fine if you are just trying to record a track or two, but if you want to do some serious recording its better to go with a Firewire interface. However, if you are just recording to get ideas down and for yourself, the line in of the computer should be fine.

 

I'm assuming the XLR out you're refering to is line-level out from the preamp and NOT speaker out from the power amp. Line level is what you want, and trying to run speaker level into your computer will result in immediate burning of computer components (I guess you already know all this, but I just want to be sure).

You are also 100% correct that using the "mic-in" input is unnecessary, as well as detrimental to the signal, and you should use the "line-in" or "aux-in" input. Trying to convert a balanced XLR mono output to an unbalanced 1/8" stereo input will take a bit of creativity with adapters, though, and it will also degrade the signal to a certain extent.

In general, In order to record to computer, it's necessary to convert the analong signal into a digital signal and this can be accomplished with the A/D converter built onto your soundcard, however, there is a huge difference in audio quality that results from A/D converters of varying price and capability and the ones found in most computer sound cards are on the very low end of the scale and will produce audio that is noticably degraded when played back through a decent sound system. Even the best, most expensive sound cards designed for gaming use are really not suited to audiophile quality sound recording.

If you're just trying to make some recordings for yourself, this may be an acceptable compromise, but if you're concerned about quality, then you'll need to purchase an interface that has the level of quality of A/D converters that you feel comfortable spending money on. There are many choices available at the "home studio" quality level (check out a Musician's Fiend, Sweatwater or American Mucus Supply catalog ) and most of these are dedicated boxes that have both microphone and line level inputs and will output (depending on options) SPDIF, USB, Firewire, ADAT/Lightpipe, MIDI and a few other options. A hundred bucks will get you a decent stereo box but you can spend hundreds or even thousands depending on how far you're willing to go with A/D converters, I/O options, and multitrack capability etc.. .

USB is very common and nearly all computers have numerous USB inputs, but USB will only handle a simple stereo signal. If you want to record multichannel (more than two), then you'll need Firewire or ADAT/Lightpipe, either of which you have to make sure you have a computer than can accept these inputs.

As for the software, any sound recording program can be used but some software is more useful than others. Choosing settings for recording, particularly the bit depth and sample rate is critical to good sound. CD quality is 16 bit, 44,100 Hz and is acceptable if you're using just the stock sound card as an interface. If you're going to use a higher quality breakout box interface, then you'll really benefit from recording at 24 bit, 48,000 Hz or even higher. You will notice the difference.