Recording Brass Quintet

Yesterday was my first time recording a brass quintet. In fact, I think it was my first time recording brass anything!

We recorded in a church that was relatively big – maybe 35ft wide and 50-60 ft long, with gable (symmetric) ceiling that was maybe 40ft tall. The room had a lot of hard surfaces – brick, wood, and some glass. As a result it had a little bit of slap back/flutter echo. It wasn’t too terrible, but noticeable when clapping my hands. I also found some fabric baffles there and placed them in front of the windows.

The band was seated in a U shape, left to right from audience perspective:
1st trumpet (D)


Tuba (“bottom” of the U)

French horn

2nd trumpet (C)


I positioned to Coles 4038 in a Blumlein array at 10′ from the line between the two trumpets and 7′-8′ high. I also added a Sony C48 as a spot microphone on the tuba. It was positioned 3′ in front of the tuba and maybe 6-7′ tall.

It all sounded pretty good! Before I settled on this arrangement, I tried the same array but a few feet back and that sounded too far, almost like recording from another room. The tuba spot mic sounded fine, not as full as I would have liked, but enough to focus it.

Here are a few things I learned in the process:

  • When recording brass for classical music, the idea is to get their projection in the room. The recording is supposed to mimic a performance, so the microphones should be outside the line of sight of any of the bells. In other words, the instruments shouldn’t project directly into the microphones. That also means that the sound will be more balanced.
  • However, the group was seated, and the trumpets’ bells were facing the floor because they had to read the score. At the end of the recording the trumpet players listened back, and they said that there was a lack of articulation and some things they were doing (like tonguing) didn’t come through very well. I myself noticed that they’re facing the floor halfway through the recording and realized I should have lowered the microphones by about a foot.
  • French horns shouldn’t be mic’ed, and that makes sense. The horn is behind the player and sometimes they stick their hand in there! It’s supposed to be reflected back.
  • If you record classical music, it’s a good idea to be able to read and follow the score! It makes communication easier.
  • ORTF can be good for recording small groups. It’ll have a more direct sound and reverb can be added later.
  • A lot of people prefer spaced omnis for classical music. I don’t have a pair of matched omnis.

One thing I’m realizing I did wrong is that I didn’t listen to the whole group play in the room. I listened to a few individual instruments (trumpet, trombone, horn) and I walked around clapping and listening to the room, but I never stood where the microphones were and listened. I should have! That’s the most important listening test! I have to remember that for next time.


I will add a short sample soon.



EV RE20/PL20 Repair, Part II

I took the top grill off and of course there was disintegrated foam everywhere. I cleaned the top grill and fixed the actual grill a little (it was pushed in).

The capsule has this little black plastic basket that protects it. It comes off by undoing the two little screws on the perimeter of the capsule. Be careful to not drop the screw driver into the capsule, though. I didn’t take a picture with the basket on, and I also started cleaning the capsule before taking pictures, but here’s the capsule with quite a bit of dirt still, and the basket before cleaning it.

A guy I talked to through the TapeOp messageboard said that he didn’t have to clean the capsule too hard to get the bass reponse back. I tested it in the condition shown above, but I still got no bass. So I kept cleaning.

At first I was cleaning with a q-tip dipped in 99% isopropyl alcohol. It worked, but I was told that the q-tip is a little too rough for the delicate membrane. So I switched to a fine artist’s brush dipped in 99% IPA. That worked well and it was better for when cleaning around the tiny coil wires or getting into the crevices. Also, the IPA is only necessary for getting the gunk loose. It can be brush off with a dry brush, and remember to brush towards the outside, away from the center.


Clean membrane, but notice the off-center pole piece.

There are still some specks of dirt under the membrane, but now the bass response was back. Check it out. I don’t have a very boomy voice, but for comparison, you can check my friend trying out the microphone on his voice prior to handing it to me.

At this point I was ready to move ahead and order new foam, clean the whole thing and work on the wiring (low cut switch is not working). However, if you’ve spent any time reading about these microphones and the ways in which they become dysfunctional, you probably saw mentions of “baby rattle”. There are examples of it online, but basically the rattle is there when the microphone is used on low end sources with fast transients. So I decide to test it on bass, and sure enough, with some low notes that were loud enough, there was this rattle that almost sounded like static. Here’s what it sounded like.

Honestly, I don’t know if that qualifies as baby rattle, because baby rattle is the result of the pole piece being loose, and this one is not loose. I also noticed that the buzzing is still there, although to a lesser extent, when the microphone is facing away from the speaker cabinet.

I asked a friend who worked on a couple of RE20s about it, and he said that he had one with a similar problem and he believed that it was dirt dirt in the motor and that some notes would make it resonate against the coil. Whether this is the problem, or it is a variant of the baby rattle or another pole piece related problem, this is the end of the road for me. I do not know how to remove the membrane, I do not have the tools to do it, and I don’t think the owner of the microphone will want to pay to learn how to do all this on his microphone. So I contacted Ben at He’s universally recommended for fixing EV microphones and his rates are supposed to be lower than EV’s. I still haven’t heard from him, so I don’t know what are his rates yet. If he’s too expensive, the owner of the microphone said that he’ll have me replace the foam, and then the microphone at least will be usable on voice.

EV RE20/PL20 Repair, Part I

A friend of a friend brought to me a very beat up PL20 to repair. At the moment it has no bass response and the capsule moves around. The foam had obviously deteriorated and needs to be replaced. I should say that I never worked on an RE20 or a PL20 before.

The first issue was trying to open the thing. YouTube has videos and people show how to do it, but basically there’s a small hex screw at the bottom of the top grill.


Location of the screw

It supposed to use uses a 0.035″ key (confirmed via the Ampex Mailing List). The screw was stripped and neither my 0.035″ or 0.9mm keys would grab onto it. I thought that maybe the screw was seized, so sprayed some WD-40 on it. When you do that, cover the grill with a paper towel or a rag so no WD-40 gets inside. That didn’t help and the key kept slipping.

Removing a stripped set screw that is sunken in its socket is tough. Some people say to use a very small flat head screw driver. I tried with one but I didn’t have a good grip on it. I went to the makers space I’m a member of and found a Pittsburgh Precision tool that had a 0.9mm bit (which I was sure was square, but looking online it says it’s hex). I put the bit into the socket and tapped it lightly so it grabbed into the screw. Then I used a handle to turn it slowly while applying some pressure. The screw came out.

I should really get that Pittsburgh tool thing, it’s cheap and it came in handy. It seems sturdy, too.