Here's the notes I have in my basic notebook for miking both grand and upright pianos:
GRAND PIANO
Most complex instrument to record; expiriment with mic placement.
Use quality condensors or extended range dynamic mics to get full complexity.
Record in isolated environment or use solo overdub whenever possible.
For full, rich sound in isolated environment, set a minimum miking distance of 5 feet.
When isolation or overdub is not possible, to reduce leakage, use close-up miking.
When close miking to reduce severe leakage, place mics inside piano, use the short prop stick for the lid, and cover the lid with moving blanket.
Also use close-up miking to get a desired effect:
- Strings and soundboard for bright and natural tone.
- Hammers for sharp and percussive effect.
- Soundboard holes alone for sharp but full-bodied tone.
Template mic placements include:
- Boundary mic on inside of partially-open lid. Good for restrictive or live performances.
- Spread stereo pair 6 inches to a foot off strings; one each for low strings and high strings.
- Single mic just inside piano between sound board and partially-open lid.
- Single mic or stereo pair outside piano facing into open lid. Good for solo or accent.
- Single mic or stereo coincident pair 4 to 8 inches off the hammers for driving pop or rock
sound.
UPRIGHT PIANO
Angle piano approximately 17 degrees from rear wall to reduce resonances.
Stereo mics just over and in front of the piano's open top. If isolation isn't a factor, remove the front face to reduce "boxy" reflections.
Removing the kickboard and placing the stereo pair 8" over the strings will give a more natural sound, but will increase potential for foot pedal noise.
G
