Imagine yourself as a fly on the wall at Abbey Road in the 1960s when Sir George helped four young Liverpudlian lads set the course for the future. In those good-old/bad-old days, the existing technology forced its users to make irreversible decisions early in the recording process. The tone of any given instrument was determined literally at the moment of tracking and, upon collapsing tracks to make room for more, was permanently cemented, eliminating the possibility for future alteration. Luckily for you 21st-century types, multitrack recording has come a long way. Even at that, the tradition has been to track guitars with whatever amplifier-generated distortion desired, semipermanently establishing a tone that would hopefully suit the final mix.
But times have changed. Now, you have some pretty powerful and easily accomplished methods for creating any guitar tone you want after the fact. Not only that, but you can do much more with a simple guitar track than ever before. You can loop, chop, slice, dice, flange, phase, reverse, decimate, vocode and otherwise tweak the snot out of them to add a bunch of unique flavor to your projects. To figure this whole process out, first look at the initial business of tracking, editing and reamping guitar tracks, and then move into the fertile ground of tweaking guitar parts for fun and profit.
RECORDED, SORTED AND DISTORTED
Everyone has seen the VH1 specials and the recording videos in which a given band and its engineer will spend hours, if not days, in the studio trying to get the perfect guitar tone. They will try out different amps with different guitars, add mics, add effects, change rooms, scream, yell — you get the picture. And even though this may yield the ultimate in perfect tonality, it's largely unnecessary for most projects. Just like soft synths have matured into instruments that are every bit as useful as their hardware counterparts, the same can now be said for guitar-amp modelers. Your DAW might be the best piece of guitar equipment you never knew you had.
The most logical starting point when recording guitar direct is learning how to get a usable, clean tone out of your guitar. For a quick fix, you can usually just plug in your guitar right to the hi-Z input on your audio interface or the instrument input on an outboard mic pre and set the level. During tracking, you might want to use some light compression to help keep levels under control, but don't overdo it. You can compress for effect later. Although all analog circuits impart some coloration, the idea here is to capture a clean signal that represents the entire frequency spectrum delivered by the guitar — you can equalize and tweak later to accomplish the tone you want.
Unfortunately, plugging in a guitar to a soundcard does not make for the most natural recording experience. Guitar amps, distortion pedals, compression and EQ have a profound impact on the timbre, literally influencing the way a guitarist plays. For instance, a guitarist hearing only a clean signal may not be palm-muting effectively enough to achieve the chunky percussive effect desired. Monitoring through a plug-in probably won't work because the latency can completely throw off the timing, which is particularly problematic with rapid playing. There are two ways around this problem: Either plug in the guitar directly to an amp and track a clean send from the amp or split the guitar's signal and send one split to the amp for monitoring and the other to the recording medium for tracking.
Once your tracks are recorded, you can send your guitarist on his or her merry way and start editing. Much as with vocal tracks, it's nice to use your DAW's automatic feature for removing the dead space between significant musical events. In Digidesign Pro Tools, for instance, the Strip Silence feature will enable you to eliminate large chunks of silence. Be sure you don't chop off the beginning or end of what you're keeping; just set the threshold such that you get the big long chunks of guitar. And if there were any timing difficulties, you can select and nudge notes, chords or entire riffs to get them more into the groove. For instance, if the guitarist played an eighth-note-based rhythm part and, during the course of the four-bar phrase, his or her timing fell both before and after the beat, you can chop up the performance at the transients and nudge them back onto the grid and crossfade the segments where necessary. The beauty of this technique is that you're only editing dry guitar, and when this signal is passed through a guitar-amp modeler, you won't be able to hear the edits.
Once you're happy with the timing and “neatness” of your tracks, it's time to audition an amp modeler. Many plug-ins are available for this type of work, such as IK Multimedia AmpliTube, Native Instruments Guitar Rig, Nomad Factory Rock Amp Legends, Line 6 Amp Farm, Apple Guitar Amp Pro (included with Logic Pro), Universal Audio Nigel, MOTU PreAmp-1 (included with Digital Performer), Cakewalk FX2 AmpSim, Alien Connections Revalver and Bomb Factory SansAmp PSA-1, as well as even some nice freeware VST plug-ins like MDA Overdrive. I did some pretty extensive experimentation with AmpliTube, Rock Amp Legends, PreAmp-1 and Overdrive; the most basic plug-ins give you the ability to overdrive a signal. The most comprehensive ones give you distortion, EQ, reverb, cabinet and speaker simulation, and other effects. Some even enable you to emulate miking with dynamic or condenser mics, placed on or off axis. These plug-ins are getting so good that even seasoned guitarists cannot distinguish them from the real McCoy in a mix. And the obvious benefit is that you don't have to destroy your back and empty your wallet with a massive array of guitar amps.
Usually, this type of processing begins with EQ (obviously, the guitar's own tone is in control at the start of the chain). Then, distortion comes into play and then further EQ. Compression at one or more stages yields even more tonal control. Use EQ and compressor plug-ins if your distortion plug-in does not include them. I test-drove a whole slew of such plug-ins from Nomad Factory and had excellent results. The most complex amp sims include all of these things, and although you may not be able to control the sequence of processing, the high-end amp sims were developed with a lot of attention to the traditional rock-guitar rigs, and you can unflinchingly trust that they got it right.
If you're an experienced guitarist, most of your real-world hardware is represented in the virtual simulations, and you can easily replicate your favorite tones. If you're not a guitarist, start with the presets and tweak from there. You can dial up nearly any tone necessary for your mix. AmpliTube and Rock Amp Legends, for example, have excellent emulations of real amps, but you can also create combinations of preamps, amps, speakers and cabinets that don't exist in the real world. There are also presets with clever names like Jimi and the Wind, November Slash, Edged Pride and SRV1. Similarly, Nomad Factory's Rock Amp Legends has stuff like Basic Tweed Lead and Run Delay (a great knockoff of David Gilmour's tone and delay in Pink Floyd's “Run Like Hell.”) Some presets are subtle, yielding nicely-colored and ambient results, and others are completely extreme, such as PreAmp-1's Pantleg-Wavin' Stack or Hades Gain.
Dynamics processing is also available, as are effects such as tremolo, delay, reverb, wah, chorusing, flanging and stereo imaging. EQ is pivotal to guitar tone, and both AmpliTube and Rock Amp Legends provide parametric in addition to 3-band tone controls. Compression can be used to increase sustain or impart a heavy, chugging punch. The amount of drive or distortion should also be one of the key parameters you tweak with. By starting with the presets and tweaking around a bit, you should be able to come up with virtually any tone you want.
SOMETHING COMPLETELY DIFFERENT
When new technology comes down the pike, studiophiles are obliged to use and abuse it in weird and wild ways. And to these ends, all of those great looping tools, pitch and time plug-ins, resynthesis plug-ins, vocoders and whatnot (which you probably already have loaded onto your computer) have the ability to take your guitar tracks to wild new directions.
A great technique for spicing up a four- or eight-bar loop of mute-picked eighth notes is to import it into Propellerhead ReCycle and slice it into its constituent eighth notes. Next, try importing it into a Dr.Rex loop player in Propellerhead Reason and panning each individual note a bit differently. For some added fun, try adding a resonant lowpass filter with a short envelope for each note. This should give the loop a synthlike quality. With the Dr.Rex VCA envelope, you can further tweak the sound by putting a soft attack on each note. Finally, add a touch of delay, and the track should really come to life.
Reaktor also has some truly incredible effects available. A particularly useful preset is the Banaan Electrique ensemble, which is perfect for arpeggiated ballad pieces. The chorusing and reverb are, in a word, gorgeous. There are dozens of tweakable parameters, far too many to list here, but it's well worth spending some time with this. The distortion in this ensemble is unique and very modern-sounding. Another killer ensemble is Fusion Reflector. This thing gives you chorusing, delays and great reverb. The GrainStates SP ensemble allows you to import any sound file and tweak it via granular synthesis. The other truly excellent ensemble that deserves attention is Vierring, which allows some really sophisticated rhythmic modulation with pattern sequencers: very powerful and very tweaky! Another way to do granular tweaking of guitar sounds is with Absynth, which allows you to import a file and do some serious damage.
Finally, vocoding is a hip way to use your recorded guitar tracks. Although synths can be used to give you a bold voice with a vocoder, there's simply nothing like a voice vocoded against a heavily distorted guitar note. It has a bite that you cannot get anywhere else. I created a distorted low E-string sustained note with the Rock Amp Legends plug-in and did some vocoding two different ways: First, I used Native Instruments Vokator and vocoded a prerecorded vocal over the distorted guitar — there's nothing quite like that sound. I also used the vocoder found in Reason 2.5 and vocoded one NN-XT sampler against another with the same files I used with Vokator. It's not quite as flexible for real-time vocoding as Vokator, due to Reason's lack of live inputs (hint-hint Propellerhead), but yields truly excellent-sounding results.