Microphones for Recording Drums
There is no right or wrong way to record drums, especially in the Pop music world where faithful reproduction is not always what is required. For many years the bass drum was recorded at a very low level, mostly due to the physical limitations of early records (L.P.s) and turntable cartridges. As technologies have improved and as artists wanted a more bass heavy sound the techniques have changed.
Early drum recordings would employ just one overhead microphone. Now it's not unusual to have a microphone on every individual drum, hi-hat and cymbal in addition to an extra one under the snare drum to get the snare wires sound and in the studio extra microphones to pick up the ambience of the room as well.
For Jazz and Orchestral drums a more purist technique tends to prevail, condenser or ribbon microphones are used as overhead microphones to record all the high frequencies of the cymbals and one microphone for the bass drum.
Bass Drum Microphones
Usually a dynamic microphone is used for the bass drum, either in front of the drum or in most Pop sessions inside the drum close to where the beater hits the skin (the front skin is removed or has a hole cut in it for microphone access), often cushions or blankets are used inside the bass drum to damp down any boomy resonance and to give a tighter ‘clicky’ sound.
Because of the high sound pressure levels from the bass drum it's best to keep one microphone just for that job since it will have to be replaced or repaired more regularly than other microphones.
The Bass drum is usually panned to the centre of the mix. The AKG D112 and Electrovoice RE20 microphones that are commonly used for bass drums.
Snare Drum Microphones
The snare drum tends to have two microphones, one for the top skin (positioned just next to the rim and pointed towards the centre of the skin) and one pointed at the snare wires. In theory the audio mixer's phase control for the top microphone's channel should be switched in because the skin is moving away from its microphone as it's hit, whereas the skin hitting the snare wires is moving towards its microphone. Experiment with the phase and relative levels of the two microphones plus equalization (eq) to get the sound you're after.
The most commonly used snare microphone Live and in the studio is the Shure SM57, if you decide to experiment with condenser microphones instead, then make sure that you switch in the -10dB or -20dB pad (attenuator) to avoid distorting the microphone’s built-in pre-amp.
The snare drum is usually panned to the centre of the mix or slightly to one side of centre. The AKG C451 range is sometimes used on snare drums, particularly for the snare wires which produce the higher frequencies.
Recording Tom Toms
Microphones can be put just inside the back of each Tom (though not usually with the ‘floor’ Tom) or just by the rim on the top looking towards the centre of the skin. The classic microphone for Toms has tended to be the dynamic Sennheiser MD 421, both in the studio and Live. Sometimes overhead microphones are used for the Cymbals and the Toms and will be angled accordingly for general coverage. When the Toms are to be mic’d up separately it’s not unusual to employ an electronic ‘gate’ on each Tom to allow it to be heard only when it is hit, thus giving a very ‘tight’ punchy sound.
The Toms are panned across the mix in the same configuration as their physical position, though avoid panning to the extremes (see Cymbals below).
Recording Hi Hat
High frequencies are created by hi-hats so it is more usual to use a cardioid condenser microphone both Live and in the studio. Care must be taken to avoid placing it where strong blasts of wind can affect it i.e. pointing to the gap between the hats. The best place is above the hi-hat pointing to the edge and away from the snare drum. If you put it below you will get too much sound from the cymbals above it.
The Hi-hat is panned to the same position in the stereo image as the ‘overheads’ (see Cymbals), also avoid panning to the extremes. The AKG C451 is a good microphone for the hi hat, the optional flexible joints and extension tubes that go between the capsule and the pre-amp allow for more optimal positioning.
Recording Cymbals
The high frequencies produced by Cymbals require either Ribbon or Condenser microphones. If these ‘overhead’ microphones are for general coverage of the drum kit then the microphones should be positioned about 2’-3’ above the kit pointing down at the Cymbals and Toms. If the Toms are individually mic’d then the overheads need to be lower (1’-2’) and pointed across in favour of the Cymbals.
Usually two microphones are used as overheads spaced 3’- 4’ feet apart and angled slightly away from each other, these are then panned left and right (at about the 9-10 and 2-3 O’clock positions) on the audio mixer, if you pan to the full extremes you risk having a drop in the level of the drums if they are summed to Mono e.g. on FM radio where the signal is poor.
Drum Microphone kits
A recent trend has been the creation of microphone kits that are expressly for recording drums. They usually consist of lightweight electret or dynamic microphones on short flexible booms that clip directly onto the rims of each Tom and Snare and then conventional microphones for the remainder, though some of the microphone kits also have clips for Cymbal and Hi-hat stands too.
These are aimed at the Live scene mostly. Examples are AKG Drum set, Audio Technica KP set and Shure DMK57-52 set.
General Hints on Drum Recording
All the microphones hear all the drums at slightly different times so the possibility of getting phase cancellations at different frequencies adds up with each microphone. Some purists use just a few microphones or a few more microphones in an Omni pattern (since they are much less prone to phase artifacts).
Some engineers use 'gates' on all the microphones except the overhead microphones. There are no fixed rules and the increased number of tracks on multi-track recorders allows you to mic’ up everything and sort it out in the mix to your satisfaction, assuming you have a large enough budget for all the extra microphones. It also makes sense to use the eq to filter out any frequencies that are not needed on each channel e.g. the Cymbals channels don't need to have any low frequencies such as the bass drum.
If you’re up against time constraints then it's best to get a good position for bass drum, snare and overhead microphones and then adjust their eq, levels and panning. When you're setting up don't set the gain on each channel to the optimum position just before the onset of distortion, allow a bit of extra headroom since when the drummer performs it's nearly always louder than the rehearsal drum hits you were given.