Recording a piano isn’t easy. The sound quality depends not just on the microphones, but on the condition of the piano and oftentimes the room where the piano is located. For the best results, keep your piano tuned and in good working order. Proper maintenance will eliminate one big hurdle of recording a piano. The rest is just a matter of good mic placement.
The piano is generally recorded using close mic’ing technique. Ideally, you’ll want a minimum of two microphones. Usually, the microphone capturing the higher strings is assigned to the left channel and the microphone capturing the lower strings is assigned to the right channel in the final stereo mix, though the stereo spread generally is not hard left and right. While a single microphone can be used, the lower and upper extremities of the instrument will likely be compromised. To capture the full range of sound, pick up a pair of instrument microphones, such as the MXL CR21 Pair or the MXL 603 Pair.
The type of piano dictates microphone placement.
Grand Piano: For the upper strings, position the microphone approximately 8 inches from the piano hammers (to reduce mechanical noise) and 8 – 11 inches above the strings, with the Pan position set to left of center.
For the lower strings, position the microphone toward the far end (away from the keyboard) roughly 6 – 12 inches from the end and 8 – 11 inches above the strings, with the Pan position set to right of center. Position the piano’s lid at full stick. (see Fig. 4A)
If you are using a single microphone, position the microphone approximately 8 inches from the piano hammers (to reduce mechanical noise) and 8 – 11 inches above the strings – centered over the piano’s mid point. Pan position should be centered and the piano’s lid should be at full stick.
Although condensers are the most commonly using mics to capture the enormous sound of a Grand Piano, ribbon mics can also be a great option. Their Bi-Directional pick up pattern can help capture both room ambiance and reflections coming off the piano (this is why piano placement matters). For example, place a ribbon microphone dead center outside the lid. With the 2 mics close-mic’ed and the addition to the ribbon you are now capturing very warm and full sound of your piano.
Upright Piano: With an upright piano, the two microphones are generally placed either just over the top of the piano with the top open, or you can remove the piano’s front panel beneath the keyboard and place the microphones below.
Front Panel Placement: For the upper strings, position the microphone approximately 8 – 11 inches away from the strings, with the Pan position set to left of center. For the lower strings, position the microphone 8 – 11 inches away from the strings, with the Pan position set to right of center. (see Fig. 4B)
Single Microphone / Open Top: If you are using a single microphone, it is generally recommended that you record from above, as placement of the microphone in the lower center may interfere with the performer’s ability to access the pedals and the microphone will likely pick up excessive pedal and other mechanical noise. Position the microphone just over the open top, centered over the instrument. (see Fig. 4C)
Experiment until you find the sound you want. The tips listed here are a good place to start.