Many engineers believe that miking a grand piano is the most difficult thing they’re called on to do. Getting it to sound natural can drive an engineer a little crazy sometimes, although that’s not always the sound we’re going for. That said, there are 4 main techniques and multiple variations of each outlined in the 4th edition of my Recording Engineer’s Handbook. Before the mics are placed though, there are a number of things to think about that help you understand why the mics are usually placed where they are. Here’s an excerpt from the same book that covers those considerations.
“The piano is a relatively new instrument, dating back to only around 1700. Although it comes in the most familiar grand and upright versions, there are subcategories to each. A concert grand is generally between 7 and 10 feet long, a parlor grand is 6 to 7 feet, and the baby grand is about 5 feet long. Upright pianos come in a studio version (42 to 45 inches tall), the more compact console version (38 to 42 inches), and the spinet version, where the top barely rises above the keyboard. All else being equal, longer pianos have longer strings and richer tone.
That being said, there are 6 things to think about before miking a piano:
1. When microphones are placed inside the piano, they can pick up unwanted pedal and hammer sounds in addition to the music, but they’ll also capture a brighter, closer sound.
2. Microphones placed outside but near the side of the instrument “looking in” can also capture reflections from the piano’s top. That can be good or bad depending on the sound you’re looking for.
3. Microphones placed away from the instrument will record both the piano and the room. If your room sounds good and you don’t need a very close sound, this is a safe method for recording a balanced piano, as the sound of the instrument doesn’t really exist properly until you get some distance from it.
4. Miking from the side usually means that the higher notes will be louder. Miking inside the case will tend to emphasize the middle octaves, which could be good for some music styles and not for others.
5. To make the piano brighter, add a few dB at 10kHz. For more definition, add a little at 3 kHz. If the piano sounds thin, adding a few dB at 100Hz helps.
6. Make sure to hire a professional piano tuner before your recording session to be sure that the piano will be in tune.”
You can read more from The Recording Engineer’s Handbook and my other books on the excerpt section of bobbyowsinski.com.