A Guide for Recording and Mixing Guitars
Recording Electric Guitar Amplifiers
For recording an electric guitar with a physical amplifier, dynamic microphones are most commonly used. A dynamic microphone is one in which sound waves cause a coil to vibrate, causing a current that's converted into sound. The Shure SM57 is one of the most popular choices.
They're good for recording guitars because they can sustain high sound frequencies, like a super loud guitar amp, and not distort. They're also relatively cheap compared to other mics.
To mic an electric guitar amp, place the microphone directly against the cabinet of the amp. This will get a punchy, direct sound. To add more ambience, you could use another mic placed further back.
The sound will also change depending on where the mic is placed up against the cabinet, so experiment! Don't just stick to dead center.
It's also important to make sure that the amplifier is properly EQ'd, or equalized. This refers to altering the high, middle, and low frequencies emitted by the amp. The controls are along the front side of almost every amplifier.
For a balanced sound, set the high, mid, and low all to 6. Certain genres of music sound better with different EQ's. A lot of thrash metal bands like to 'scoop' out the mids, crank up the lows, and almost max out the highs. This gives the guitar a very nasty sound, and accentuates palm muting.
Basically, lows will give the guitar a bassier sound, middle range will brighten up chords, and high frequency amplifies the higher register notes. However, in excess, any of these can cause problems, so experiment with each frequency in the 5-7 range, and stay away from 10s.
Recording Acoustic Guitars
Acoustic is a different ballgame when it comes to recording. There's no amplifier, so we record directly into the guitar. Instead of dynamic microphones, small-diaphragm condenser mics tend to be of choice.
This is because the condenser microphone captures a larger frequency range than the dynamic mics, and has a better transient response. A transient refers to an abrupt change in audio level, such as strumming loudly on an acoustic. Condenser mics have the fastest transient response, so they capture these sounds the best.
To mic an acoustic, it's a good idea to have the mic directly above the sound hole about 10 inches or so. Give adequate room for the performing musicians hands not to hit the mic. It's best if possible to record in a condensed, sound proofed room.
If this is not available, do your best to turn of all exterior noises. This could be a fridge, a ceiling fan, electronics, etc. Do your best to create an environment that is almost completely neutral of other sounds.
Recording Amp Modeling Software
Nowadays, amp modeling software is becoming more and more prevalent. Certain DAW's (digital audio workstations) even come with tons of options for amp modeling, such as Logic Pro X. However, many of these sounds are hit and miss, and recording a live amp is usually the best option.
That doesn't mean these softwares don't have their use though. It is possible to acquire believable and even studio quality guitar tone with them, you just have to be very picky.
When recording a heavier sound with software, try not using the distortion pedals included. These tend to only muddy the sound. Instead, record several tracks of a modeled amp with the gain set to about 4 or 5.
When you combine these tracks together, they will combine into a high gain sound that won't sound muddy because it's made up of fairly clean takes. Also, try experimenting with panning each take to a different speaker.
The number of options when mixing can be overwhelming. However, getting down a few key basics will help make every track shine. When mixing together electric guitar tracks, try blending two different takes. In other words, instead of copying one take to double it up, have the performers record two separate takes.
This will give the guitar an organic sound, as both takes won't sound completely the same. If you want to take it even farther, you can have each take vary slightly on the way the song is performed. Guns N' Roses was famous for this, as their guitarists were never playing exactly the same thing.
Also try using two different amp sounds for each speaker. Have one amp in the right speaker, and another in the left. This will add depth to the sound, and give the tone a different feel.
When it comes to EQ, there again are many, many options. The most basic principle for EQ is space. Every instrument or vocal should occupy it's own frequency space. If two instruments share the same space, it will sound cluttered and muddy.
For example, if you have a track consisting of bass, guitar, drums, and vocals, the EQ would go like this. The bass track would have the low end boosted, while cutting out the middle and high frequencies.
The guitar would have the low end cut out so the bass can occupy that space, and would mainly retain it's middle frequency, and some sparse higher ones.
The drums would occupy a little in each space. Low end for the kick, middle for the snare, and high for the cymbals. The vocals would occupy mainly in the high range, with some mids left in.
By doing this, each instrument has its own space in the mix, and they will all pop. However, this rule is not set in stone. Many heavy acts like to keep the low end in the guitar, since they feature heavy down-tuned riffs. For this music, cutting out the low end would harm the guitar sound instead of improving it.
Listen to your song and determine what would be best for it. Do you want low, beefy riffs or soaring high solos? Bright, chiming chords or booming bass? Decide what's best for each particular song, and of course, experiment!