Let's look at how to mic a guitar amp. Miking the amp in different ways can
drastically change how the guitar will sound in the mix. This is a very
crucial step. If you're a guitar player or have been around one, then you know
how much work goes into getting just the right guitar tone.
Choosing a microphone that can work with high levels is really important.
Because of this, dynamic mics work exceptionally well. If you choose to
use a condenser microphone, make sure that the mic isn't overloading from the signal.
To get around this, you may want to move the mic further back from the amp
speakers. You can also use a condenser mic that has a pad switch on it.
Now, you have a mic picked out that you're ready to use. Deciding what you
want to pick up is the next step in mic placement. The further away from
the amp the mic is, the more room sound there will be in the recording.
If you're miking the amp close to the grill, you can now choose where to
place the mic. Small adjustments around the cone of the speaker will have
large results. Generally, the closer the mic is to the center, the more
the guitar will sound bright and edgy. Moving towards the outer edge of
the cone will produce more low end and smoother tones. Another option is
to aim the mic off-axis. Aiming the microphone straight at the speaker
cone is called on-axis. Having the mic aimed at an angle towards the edge
of the speaker cone is known as off-axis.
Another way to go would be to use two mics. This could be one dynamic on
the grill of the speaker, while the other is a condenser mic put back away
from the amp. The condenser would pick up more of the room sound. You
could instead choose to use two different dynamic mics close to the speaker.
This is a really common guitar amp miking technique. The shure sm57 and
sennheiser md421 are really popular choices for this set up. Other options
to look at are adding a DI signal or adding a microphone placed behind the
guitar amp speaker. If you choose to place a mic behind the amp, make sure
the phase is reversed on the microphone track.
Alright, turn that guitar amp up, dial in the tone, and get those mics
placed right where you need them to get that guitar track recorded the way
you want it to sound. After that you can make it sound great in your mix,
instead of having to spend lots of time correcting things on the track that
are a result of bad miking techniques.