Boundary Microphone Piano

Anonymous067

Active Member
hey all. Preparing to mic a piano with a limited selection of microphones. Right now, the "best" choice I have is an AT 851 boundary microphone.

Has anybody tried this on either an upright or grand piano, liked or disliked the results, and how did they use the microphone in the piano?

Just trying to get ideas. I know this has been discussed before on CB but I wanted to know specifically the AT 851 if possible.

thx
 
Boundary mics can work nicely in a grand piano. I have used Crown PZMs with a hemispherical pattern in pianos. You didn't say whether the piano is a grand or an upright, and whether you need mono or stereo. I have never had good luck micing an upright on the inside. They sound boxy and artificial that way. From the back sound board is usually better on an upright. Did I mention that I HATE the sound of uprights?

For a grand piano, gaffer taping the mic to the lid is the way to do it with a boundary mic. Be careful to tape the cable so that it cannot come in contact with the strings. Placement changes the character of the sound a lot , so it's worth experimenting a bit.

With one mic for mono, I would try placing it about a foot from the hammers, and centered on the keyboard, with the "front" of the mic toward the hammers (the 851 is a cardioid). If you need isolation, close the lid, but the short stick would probably sound the better.

The 851 may not be the best choice because it has a pretty broad, 10 dB high frequency boost, which could make it rather bright. Such a boost is nice for voice but not for most instruments. Another thing you can try is to use a reasonably flat instrument mic on a straight stand. Put it right at the crook of the piano (the curve where it narrows), pointed toward the middle hammers. Prop the lid open just a couple of inches with a block of wood, with the mic sticking inside. This will give a natural sound for jazz and acoustic music, but may not be close enough to the hammers for rock sound. An AT Pro-37 would be an inexpensive choice for this method.

If you do go with the 851, replace the gaffer tape every show day. I once had a PZM go plunk into the strings right in the middle of a show because the tape gave up after a few days. Not a good sound laying on strings. Do not use duct tape, and be sure to remove all tape when you are done so as not to harm the piano.
 
I think I mentioned I don't know if it will be an upright or grand, because it hasn't been decided yet. I'm pushing for the grand, but I really don't know yet.

I don't have any more budget to buy or rent anything else. I'm already maxed out. Could a little EQ help pull the high end of that 851 one way or another?

I'd also like to use a boundary mic on the inside because it's less stands, and less repositioning I have to do.

My goal for this show is not have to go backstage at all. I want to sit down at the board and stay there. Anything to help that go smoother will be nice.
 
If the piano has to move during the show, something attached inside is probably the way to go. EQ on the console might help, but I would start by adjusting mic placement. Get the best sound you can that way, before messing with EQ. EQ should be the icing on the cake, not a fix to something bad.

You can change the sound greatly by mic placement. Get some time with the pianist when others are not around and you can try things without rushing. Most musicians will be up for that because you are going to help them sound their best. Don't be afraid to experiment. It'll sound different over sound holes, closer to the hammers, away from the hammers, favoring low strings, etc.
 
Here is a link for some of the options, including boundary mics.

The Doghouse NYC - Recording the Grand Piano


One trick is to start by listening to where the piano sounds best, typically cupping hand over ear etc. this can give you a good starting point. Remember that PZM boundary mics like the Crown ppc 160 are cardioid and so orientation is important. This is why some setups have them on the edges of the lid pointing in

here are some other tricks

http://www.crownaudio.com/kb/entry/257/

here is a picture of the lid with the strings reflected, giving you an idea of the v formation option

http://www.rraud.com/images/synod/mics.html

Sharyn
 
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In a similar discussion elsewhere, boundary mics do not seem to be well liked for piano (although a few folks like them).

A method that does seem to be well liked is to take any decent cardioid and point it into the third hole. (But is the first hole on the low or the high side? They never say.)
 
I have used a boundary microphone on a grand piano and have found it unsatisfying. The exception was when I used two taped to the lid. As for an upright, boundary mics just won't cut it. My preferred method is two small diaphragm condensers in an XY pattern on a stereo bar. Sounds great but not great for protability. The one advantage I have found with boundary mics is that minde can be used with my wireless system with the bodypack transmitter taped inside the curve of the piano. If you can find any way to avoid boundary mics I would, but if not play with the placement to find the best sound you can.
 
hey all. Preparing to mic a piano with a limited selection of microphones. Right now, the "best" choice I have is an AT 851 boundary microphone.

Has anybody tried this on either an upright or grand piano, liked or disliked the results, and how did they use the microphone in the piano?

Just trying to get ideas. I know this has been discussed before on CB but I wanted to know specifically the AT 851 if possible.

thx

Generally speaking I prefer to use SDCs (like sm81s or 451s) or the 414 out of the studio. However, if I need to hide the mics, or if the piano has to move then boundary mics are...an acceptable trade off.
I've used crown PCC160s in grand pianos, although I don't like taping them to the lid. I've seen the Gaff tape come off (it does happen occasionally) and drop the mic onto the strings. Luckily it happened during a move not an active part of the show. that could have been one ugly sound, and probably not good for the strings. I've also had problems taping boundary mics to the lid of a piano because the lid become a soundboard for any extraneous noise and stage wash, which then couples into the mic.
I prefer to tape mine to the inside of the curved side of the piano pointing down at the soundboard. Location is somewhat to taste, but I've found the best results with one in the area of the first (lowest) hole and one farther up on the curve, near the higher strings. Mix to taste with the lower mic carrying the majority of the sound and the hi mic adding sparkle as needed.
Matt
 

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