Some of the most popular instruments in many genres of music are keyboards, so let’s look at some recording techniques to capture a grand piano, upright piano, Leslie organ speaker, digital keyboard or synthesizer.
This magnificent instrument is a challenge to record well. First have the piano tuned, and oil the pedals to reduce squeaks. You can prevent thumps by stuffing some foam or cloth under the pedal mechanism.
One popular method uses two spaced mics inside the piano. Use omni or cardioid condenser mics, ideally in shock mounts. Put the lid on the long stick. If you can, remove the lid to reduce boominess. Center one mic over the treble strings and one over the bass strings.
Typically, both microphones are 8 to 12 inches over the strings and 8 inches horizontally from the hammers (Figure 1). Aim the mics straight down. Pan the mics partly left and right for stereo.
The spaced mics might have phase cancellations when mixed to mono, so you might want to try coincident miking (Figure 1-A). Boom-mount a stereo mic, or an XY pair of cardioids crossed at 120 degrees. Miking close to the hammers sounds percussive; toward the tail has more tone.
One alternative is to put the treble mic near the hammers, and put the bass mic about 2 feet toward the tail (Figure 1-B).
Another method uses two ear-spaced omni condensers or an ORTF pair about 12 to 18 inches above the strings. With the ORTF stereo mic method, two cardioid mics are angled 110 degrees apart and spaced 7 inches horizontally.
Boundary mics work well, too. If you want to pick up the piano in mono, tape a boundary mic to the underside of the raised lid, in the center of the strings, near the hammers.
Use two for stereo over the bass and treble strings. Put the bass mic near the tail of the piano to equalize the mic distances to the hammers (Figure 1-C). If leakage is a problem, close the lid and cut EQ a little around 250 Hz to reduce boominess.
If your studio lacks a piano, consider using a software emulation of a piano. Some programs provide high-quality samples of piano notes that can be played with a sequencer or a MIDI controller.
Moving on, here are some ways to mike an upright piano (Figure 2):
A) Remove the panel in front of the piano to expose the strings over the keyboard. Place one mic near the bass strings and one near the treble strings about 8 inches away.
Record in stereo and pan the signals left and right for the desired piano width. If you can spare only one mic for the piano, just cover the treble strings.
B)Remove the top lid and upper panel. Put a stereo pair of mics about 1 foot in front and 1 foot over the top. If the piano is against a wall, angle the piano about 17 degrees from the wall to reduce tubby resonances.
C) Aim the soundboard into the room. Mike the bass and treble sides of the soundboard a few inches away. In this spot, the mics pick up less pedal thumps and other noises. Try cardioid dynamic mics with a presence peak.