Boundary mics?

larryace

"Uncle Larry"
I can't seem to got a room mic to work for my studio recordings, so I am considering boundary mics. Room mics really detract in my space. Or they add stuff I don't want. One of them.

My ceiling is like 6 feet 7. The room is 20 x 12. I was considering putting a boundary mic on the floor somewhere. So I could have a bunch of room between that and the ceiling. I will try a condenser mic that I already have first...on the floor pointing towards the ceiling, but I haven't done that yet...to see if a boundary mic is warranted.

Can anyone share their experiences and recommendations for boundary mics?

Thanks!
 

Vintage Old School

Gold Member
Can anyone share their experiences and recommendations for boundary mics?

Thanks!
Most of my experience over the years with boundary mics has been with Crown PZMs for theatre and drama applications.
They typically sound thin, metallic and have a high degree of self noise.

In film/video applications the use of boundary mics is mostly to capture clean, clear dialog. The one boundary mic that rises
to the top that should also excel in capturing music is the Schoeps BLM 03 Cg because of its high quality studio condenser
element, hemispherical polar pattern and low self noise. Be prepared--it is pricey.

I'd encourage you to borrow or rent a boundary mic first to see if you even like the results.

I'd also recommend contacting Audio-Technica USA and tell them how you intend to use it. AT makes good, price friendly boundary
mics, but the benefit of talking this through with them is that they may recommend a much better solution for your needs.

My two cents worth.
 

cbphoto

Gold Member
My very first mic was the Crown PZM-6D with power supply. I bought it for its high SPL spec, easy to use (no mic stand needed, rugged) and to give me an idea of how balanced I played the kit (I didn't). I wasn't after high fidelity recording, I just wanted the truth about my playing. I used it daily for years, and still have it.

There's many ways to use a PZM, my fave was to place a sheet of plywood about 6' in front of the kit, on the floor along the long edge, at a slight angle and hang the mic so it rests in the center area (tables placed on their side work well, too). A large surface area seems to help pick up & transmit lower frequencies to the mic for a fuller sound.

Since you have low ceilings, you can try mounting it on the ceiling directly above the kit (gaffers tape works if the wife isn't around). Another method is to hang it around your neck with the idea that it picks up what you hear from your seat.

When I first started using it, I simply placed it on the floor under the snare to pick up the snare & kick (it picked up everything else, too). An example recording of this method is here. This was made c.1995. Please be kind. It was one of my first attempts with GarageBand and the "horns" will make your ears bleed. The room in this example was 12'x15'x6' high ceilings with cinder block walls; Not ideal.

Is it possible to get high fidelity recordings from a PZM? I think so, with the proper placement in a decent room.
 

alparrott

Platinum Member
I'm a HUGE proponent of boundary mics both for recording and for live playing in small-to-mid-sized venues. I have two in my kit: a Shure 819/881 (the precursor to the Beta 91A) and a Sennheiser E901.

Typically, I use the 901 as a bass drum mic. I run the XLR in through a small hole in the shell and the mic rests on top of my muffling pillow, which has a little bit of nylon cord around it. I tuck the 901 under that cord and it stays put no matter how hard I play the drum.

Reading the manual for the (now discontinued) 819/881, I was interested in how they recommended putting it not inside the bass drum, but just in front of the front hoop on the floor facing the bass drum. I was able to get a very serviceable whole-kit sound just with that one mic for demos and fooling around. I started taking it out to gigs, with the intent of primarily using it as a self-monitor mic in my IEMs. For whatever reason we needed some of me in the FOH mix and so I suggested my in-front-of-the-hoop trick. It worked a treat. We even have used it in large venues such as open-air festivals and RV rallies when a full mic kit wasn't available, and the sound was really quite good.

The e901, like the Beta 91, has a true bass drum freq range compared to the 819 (which only gets down to 60hZ compared to the 901's 20hZ), so I have started taking that one along instead for a deeper sound. It also uses a real XLR instead of a mini-XLR, so I'm not as worried about it getting broken by a guitarist misstep.

I intend to try using the 819 as a room ambient mic in addition to close mics. I don't have enough inputs on my current gear to pull that off, but I think it will excel in that application. It also makes a pretty cool under-snare mic (although it is really picking up everything, not just the snare).

Boundary mics come in all prices, but the e901 is my recommendation hands down. It's about $250 new.
 
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Vintage Old School

Gold Member
I'm a HUGE proponent of boundary mics both for recording and for live playing in small-to-mid-sized venues.
Boundary mics come in all prices, but the e901 is my recommendation hands down. It's about $250 new.
I second what Al says about the Sennheiser e901. I've started using it inside my kick drums and it's wonderful.
The only reason I didn't mention it is because it's EQ'ed for bass drums. Didn't know if you wanted something to
capture the entire frequency range that you could selectively EQ yourself.

I need to experiment with it outside the bass drum on location.

For the money it's a steal. Really, really nice boundary mic.
 

alparrott

Platinum Member
I second what Al says about the Sennheiser e901. I've started using it inside my kick drums and it's wonderful.
The only reason I didn't mention it is because it's EQ'ed for bass drums. Didn't know if you wanted something to
capture the entire frequency range that you could selectively EQ yourself.

I need to experiment with it outside the bass drum on location.

For the money it's a steal. Really, really nice boundary mic.
I used it outside the bass drum on a gig last fall, in a medium-sized room. It was pretty great for pushing the low end out to the back of the room, and for capturing the mids of the kit, but rolled off enough of the highs from the cymbals to make a real nice mix in the audience. I take it with me every time now.
 

larryace

"Uncle Larry"
Update: I finally found the trick to placing a room mic properly in my space.

For starters, I used the nicest condenser mic I have. I basically found that if I position it the same way as I would a boundary mic, the room mic now yields an acceptable capture. Took a while to figure that out. I place it low, almost touching the floor, (emulating a boundary mic) on a 45 degree angle in relation to the ceiling. So it's like the mic is in a room with a high ceiling lol. I put it almost in the center of the room, which is only like 6 feet in front of my 2 x 4/plywood drum riser.

I tried this setup in 3 other locations, even in the next room, and for now, this is the best placement. Until I find a better one. I only experimented with one mic too. It's never-ending lol. But very stimulating to me.

Finding optimal mic positions would be a crap ton easier if I had 2 other people....one to play the drums and one to move the different microphones around to try and locate sweet spots...while I listen with my eyes closed.

I'm going a little nuts trying to completely optimize what I have here...I put the legs of every stand I have on the recording kit on dense foam rubber, I even put foam rubber under the footpedal plate. It seems to quiet the natural resonances transmitted through the riser. I should probably lose the riser but I won't. I like storing my mic stands underneath.

The process as it is now, is playing and recording the drums, listening back, checking meters, adjusting gains, moving mics, playing and recording drums, listening back, checking meter, adjusting gains moving mics etc. Try that 10 times lol. It's mentally draining lol.

I recorded another drummer the other week, with the settings on the gear set for how I hit them...and the drums sounded totally different when he played them, and not in a good way. IOW, I would have to set gains for each individual player. Everyone's touch and individual volume balancing act is different. It's nuckin futs.

Since I got a better handle on the room mic thing, it doesn't seem that I should be needing any stinking boundary mics.

I appreciate all the comments though. I did learn some.
 
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