I'll usually record three main rhythm tracks: Left, Right and Center. I use Guitar Rig and AmpliTube primarily because I can blend the sound after recording (i.e. dial down distortion to fit the soundscape). I can not record clean, as I find it a bit uninspiring for a distorted part. I may put the center channel clean with some eq, and then move it down in the mix. Once I get the 2 or 3 takes I like, I archive the unprocessed performances.
 
And to second what Johnny said: different chord voicings can add a LOT underneath the main part as well.

Cactus Music
I also will double acoustic rythym tracks, not just the crunchy ones. Play the same thing twice.. it always takes me a few takes ( sometimes more than a few) to be happy anyways, so one more take is easy by then.
Another trick for both electric or acoustic is to put a capo on and have a different chord voicing. Power chords are excluded from this idea as there's no point in a capo with a power cord  ;)

But you can voice power chords in different registers and/or on different strings and/or invert the notes to expand the sound.

Cactus Music
There's no point in a capo with a power cord  ;)

 
Cool quote alert! Tweetable content!

Jim Roseberry
 
If you're looking for a big/fat sound, start with the instrument/amp.

Agreed.
Expanding a bit on that from my experience, string / action height and pickup height can have a great deal to do with the sound of the guitar and how it drives the amp or virtual amp.
The higher the action the more room the strings have to move.
The lower the pickups the less magnetic restriction on the strings = again ... more string excursion.
Of course the action height thing is also about a physical comfort zone but I'd always recommend don't be afraid to step out of the comfort zone and let it grow on you a bit.

I usually find a place with the action /setup where it begins to be high enough that I start to really relax and play more calmly, and with a lighter touch. Too low of an action always makes me struggle and want to dig in too much, probably because I'm not getting the sound from the strings.

When it feels like there is airy space under the strings and it all gets easy is when I end up getting the sound onto the (virtual) tape.
 
I also agree there's no substitute for a "real" double track. It's also a great way to tighten up the performance, as like,
cut the first one, cut the second while listening to the first, and the second one "adapts" a bit.

Now mute the first one and cut a 3rd while listening to the second.
The listening mix and balance / panning can be critical in this process but what I look for is letting the track I'm monitoring tell me how to fit with it. It's find the magic. When I hit that spot I'm just letting it happen as opposed to controlling it.
Sometimes I'll try 4, 5, or 6 to see how far it can go.
For me the trick is not getting too cold, and knowing where the heart and or guts of the performance wants to be for this particular part.

Sanderxpander

Kylotan

Sanderxpander
Doing that with just two tracks should have the same effect. Anything that you straight up double left and right is basically the same as a louder centered version.

Some people are talking about nudging tracks slightly, which will help create some amount of stereo depth rather than just sounding like a loud centered track. But it will also create some phasing artifacts and probably won't collapse to mono very well. I prefer to record the part twice and pan those. That's how most rock recording artists work.

I agree but using two identical tracks on both sides and nudging one of each still leaves two identical unnudged tracks left and right. Which is the same as a single centered track. That's why I said doing it with just two tracks (nudging/delaying one) should have the same effect.

We'll have to agree to disagree. Each to his/her own.

You do get a richer sound, i feel.

The importance, again, my idea, is to record the tone you want correctly, and as a dry signal. I use either an RP500 or ME80 direct into my LS56 THEN add reverb or delay to enhance the effect. You can play around with which tracks you actually place the reverb on, and, if you want, add an EQ..... There is no limit to the imagination !

Again, my way that i wanted to share.

Cheers,
Jerry

Just for the sake of clarity, I'm not talking about recording a part twice and panning that. I'm talking specifically about panning the SAME track (no delay/nudge) left and right. Are you saying this gives you a richer sound than a single centered track?

Thank you everyone, great points made here. My general rule is to not multi track the guitars with the same amps or in this case modeling (which after a YEAR of tweeking Line 6 and Overloud plug ins) Ive got killer results. I record with a fairly saturated tone with guitar 'A' and then use a much cleaner tone and guitar 'B' for the double. The doubled tone by itself almost sounds TOO clean but as stated here the combo of the two tones together is big and fat yet retains definition. Again, thanks everyone! 

sharke
You may find this a very interesting read (if you can get past the bad language - but hey, that's Slipperman for you!)
 
http://www.badmuckingfast.../sound/slipperman.html

Best article of micing guitars I've read in a long time! Worthy of a Pesado Award for sure lol!

Sanderxpander
Just for the sake of clarity, I'm not talking about recording a part twice and panning that. I'm talking specifically about panning the SAME track (no delay/nudge) left and right. Are you saying this gives you a richer sound than a single centered track?

Yep, to my ears. I don't like using software effects like Guitar Rig et al (even tho' I have version 5).
 
As I said before, its the way I do it and it suits me fine.
 
But that's not what is important. The point is there are many different ways of how to do it, as explained in this fred, by many different people. There is obviously NO right way, and if I may say, no wrong way.
 
Cheers,
Jerry

I'll be the purist in a sense here, since I routinely track a massive, but punchy-sounding Les Paul through and old 5150 half-stack, and I'll make a recommendation that I have tested and tested, and tested over and over:
Get a loud amp with fresh tubes, and plug the guitar directly into it on the Overdrive or distortion channel. I have never ever heard a guitar that comes close, and that's not a scrutinizing ear, that's just a notably discernible difference that can be heard in the final recording. Even the common listener can tell a difference if you A/B different guitar tracking methods. 
 
Get in the room with the guitar amp, and tweak it until it really does what you want in the room. If you track multiple cabs, I personally recommend putting each cab in a different room. Use one decent condenser mic, even a tube mic (I use an Avantone cv-12 often), Find the right distance by listening and mic the upper speakers, if you can. The lower speakers will give you reflections from the floor. Listen, tweak, listen, tweak, and so on. Once you get the tone you want, I'm serious, there's no EQ you'll need afterward.
 
For copying takes over and playing with the phasing to create a thicker, stereo effect, you are better off tracking twice instead of copy/paste/phase. However, in a 20-year old session I'm remixing, where there was only one guitar, and I need two, I've learned to copy it twice. Put two of them on the far left/right, and one in the center at a lower level so that when they collapse you're more likely to save some tone in mono. Play with the phase, but run the signal through a tube amp and re-mic it to allow yourself some variances on how well they sound when panned left/right.
 
I've tried re-amping each one through a different head/amp, and I've even re-amped a guitar through another guitar's pickups by either tapping into the coils, or blasting the signal across a single string on a guitar plugged into an amp cranked up and mic'd. Mixing some of these weird elements into the mix, you can open up some interesting opportunities with a single guitar track!
 
NOTE! If you are going to phase a copy of a guitar track to create a stereo effect, not only is mono a challenge as to not cancel out the tracks, ensure you're not exactly 180-degrees out of phase between the two waveforms. BUT, don't overlook headphones vs. monitors. You will often find the left-right balance relationship changes drastically between monitors and headphones.