Traditionally the best way to record your guitar is to get a good microphone and put it in front of the speaker on your amplifier.
The reason for this is that to get that raw guitar sound it’s much easier to record what comes out of the amp because plugging straight into a mixing desk or USB audio interface like the M-Audio Fast Track Pro you’ll end up with a sound that’s too clean.
Although you can add effects and reverb to the track afterwards these things can have a profound effect on the way you play the track in the first place.
The Amp + Microphone Method
Micing up an amp although an obvious solution is not the most practical for every home studio. Professional engineers like to have the amp in a separate room all on its own.
To get the most out this method you’ll also need to experiment with placement of the mics and amp around the room – depending on how much space you have. Another reason using the mic and amp technique does not seem that viable is that you may not be able to crank up your amp to the required volume to get a good take. Add to that the fact of the mic picking up surrounding noise if it’s not loud enough to drown out everything else.
Using Software ‘Guitar Racks’ and Direct Input Units
Another option is to plug your guitar directly into your sound card, USB interface or Direct Input (DI) unit and record using software effects. When set up this is a very cost effective and acceptable solution for many.
But what if you’ve played around, researched and nurtured that perfect tone from your amp? Well if you’re lucky your amp just might have a DI output or even a headphone socket that you can run into your soundcard/USB interface or DI.
What works for you will depend on a lot of variables such as budget, space, what you already have, how loud you can crank up your amp, computer interfaces and more. I’d say the order of preference for the best solutions would be:
1. Mic up a good amp and capture that perfect guitar tone you’ve developed
2. Get your amp to output into the mixing desk (or computer interface) via DI or the headphone socket
3. Plug the guitar straight into your computer’s soundcard/USB interface or DI unit and use software effects and reverb.
I personally am exploring option 2 as I want my amp sound when I’m playing the track as it affects the way I play it, however I can’t crank it up too loud and I want the option to record my ideas and jam at 4am.
And my amp has a DI output socket
For a more detailed look at recording guitar I recommend you read this article by Paul White at Sound on Sound:
Recording Electric Guitar