I play in a British style brass band, and have been asked to record a couple of rehearsals. I'll probably also eventually do a recording and video of a couple of concerts, but that's down the road a bit.

A "British Style" brass band is just that - brass instruments only, no clarinets or flutes etc, and about 24 players.

I think I'm OK on equipment, but need a bit of advice on a couple of other items.

The rehearsal space is long and narrow (ie a storefront dance studio that lets us use the place in the evening for a sum that's "within our nonexistent budget")

The band sits facing one of the long walls. I'll be able to place mics above and slightly behind the director, but will only be about 3 feet from the middle of one of the long walls.

There is an air conditioning duct running the whole length of the ceiling and wall just behind the director, with outlets every 8 or 10 feet. I've listened pretty carefully and don't hear any A/C rumbling, but the air whooshing out of the vents is quite audible. This is Southern Arizona, so turning off the A/C isn't an option for us.

Fortunately, there isn't a vent directly in back of the director, but there is one on each side about 4 feet away.

These recordings don't have to be highest quality as they're going to be used to help in analyzing balance and dynamics, but at the same time I don't want to do a poor job either.

Questions:

1) Any concerns about probems that might arise from being so close to the wall?

2) Any suggestions re eliminating or minimizing the sound of the air flow, either in setting up the recording. or in post processing.

I had thought of capturing a couple of minutes of the ambient noise by itself and using it as a filter in post, but not sure it would be effective. I'd also wondered whether using a high pass filter would eliminate a significant portion of the airflow noise.

Any ideas/suggestions/comments welcome.

An English Brass Band smack into a wall? Air Con? Wood floors? Concrete ceiling?

Talk about "boldly going where no one has gone before"!

Well, for the AirCon, if you can get a couple of blankets and duct tape them over the top (just the top, let the blanket just drape over the outlet) of the outlets, so that the airflow still flows but has to fight it's way past the blanket, it should kill a lot of the wind noise.

To my mind the biggest problem is going to be the backwash of HF audio off that wall and then whatever is behind the band. I would suggest drape the entire wall with blankets, but there is a point where it simply won't be worth it.

Maybe "close mic" to extreme and keep the gain down so low even a shout is muted might work but hey, I'm clutching at straws now.

I'll be interested in what other suggestions are forthcoming.

Good luck.


CS

Thanks much for the comment.

At least the individual fans in back of the band will be off.

I think doing anything to disrupt the airflow will be poorly received by the gang - we're now into our "cool" autumn season where it's only in the low to mid 90's during the day.

http://www.wunderground.com/US/AZ/Tucson.html

I was thinking of possibly putting some kind of acoustic damping up behind the mics.

Fortunately the place is carpeted over concrete floors and has drop ceilings so the room isn't particularly "live". and it doesn't sound anywhere near as bad as you might think. Not ideal by a long shot, but not as bad as some rooms I've run into.

I think the biggest problem is the A/C. I guess I'll know in a few days!

The suggestion re the AirCon isn't quite as lethal as you might think.

If the blankets are duct taped above the outlets, and held off the outlets by something as simple as a ruler (say) the air has plenty of room to exit, but it, and any sound, is directed straight down to the floor.

You can, at a push, use good 'ol cardboard. Doesn't absorb quite the "rush" but still directs it off the mic's and straight down to the floor. You'd be suprised the difference it makes.

Job done. Used it heaps of times (both ways) and it works.


Good luck.


CS


CS

Chris,

Thanks for the suggestion. I'm still having a bit of a problem picturing the setup, though. I guess I'm worried that without enough horizontal "throw" from the vents, the guys in back about 20 feet from the vents won't get enough air flow to stay cool. I think I'll play with this here in the house, as we have vents high up in the wall about 10 feet off the floor, so I should be able to do at least a rough simulation.

Of course, I realize that anything I do is likely to be a band-aid as opposed to a cure, and the best way to do it would be to use a better rehearsal space.

One thing to try that might also help is using omni mics. If you're OK with the current reflections and sound, I would try to run a decca tree with three omni mics. I've run a configuration like this directly behind a conductor without any issues. The AC wind will be helped with the omnis, but you will probably still want to put some type of wind sock on them if you still hear the noise using omnis.

Good luck!

Wayne

I would get 2 large diaphragm mics in an XY configuration above and behind the directors head with the capsules opposing each other at 110 to 120 degree (not 90) utilize the high pass filters on the mics and set them to cardioid pattern, AKG 414buls, Neumann U87, but those are expensive, however AT4033 are cheaper and are decent as well as rode NT2 or even NT1s , if you dont feel you have a need to purchase then track down your local PA rental house and rent them you wont be disappointed. place 2 moving blankets on back wall behind the mics (2 layers I mean), and shut the 2 nearest ac Vents, duct tape plastic over them if necessary (if they whistle) ...... 2mics ,2 mic stands, 2 XLR cables, one 2chanel mic pre w/phantom(small mixer), and your recording device, and youre good to go. if you want to make the recording better then add a compressor between the preamp and the recording device and you can squeeze a bit more volume with out clipping your recording device. the only thing that can ruin this setup is a bad performance, or environmental noises that YOU cant do anything about. so try it and have fun I think you'll be amazed... by the way be carefull with the volumes horn bands are notoriously dynamic, watch your recording levels.

You can certainly expect the AC noise to be more noticeable in the recording than in the moment. It's a perceptual thing. A high pass filter would probably do more to distort the music than to quell the noise. It's called broadband noise because of the mix of frequencies in it. The good new is that broadband noise filters in commercial software are usually effective with air conditioning. I use the standalone program, SoundSoap, but there are noise reduction functions in some audio programs too. Do get a sample of the noise if you might potentially use such a program. You want the sample with everyone in the room so it is representative. Just have everyone be really silent for a few seconds.

David,

Thanks much. I've done something similar when ripping LP's by recording the space between the cuts and feeding it to the noise removal function in Audition. Not perfect but quite an improvement. When you look at the spectral display of before and after you see significantly less clutter.

I wasn't sure the same trick would work with A/C noise, though.

If the recording is for performance analysis only then record it with out distortion by getting your levels right and with plenty of headroom.

An X-Y pair in front of the MD will be fine. Cardioids are fine or just place a single omni there.

Make sure wind is not hitting the mic's.

Save the attempt at a perfect recording for a decent hall/concert performance.

What matters for this gig is a clean reference for the MD to listen to. They may neither notice or care about the aircon as they will certainly find enough fault with the performance to eliminate any prospect of issuing the recording and any recording that might be attempted down the line would need a decent recording environment as it's first requisite.

Jimmy,

Thanks much. Yes, it's for analysis and not for distribution. And most of the fault will be with the musicians (including me!)

On the other hand, it's a good opportunity to try and get as good a recording as I can, given that the room constitutes an almost perfect (sh--) storm of problems. If it sounds passable here I can probably make it sound really nice anywhere else! I'll have quite a few opportunities to play with it, as we rehearse every week, so am looking for ideas re a starting point.

If the A/C noise is able to be minimized in post, then I'll be able to focus more on the other problems. I was thinking to put a couple of diffusion and/or absorption panels in back of the mic to try and kill off at least some of the nearly instantaneous reflections off the wall. I have several 2 x 4 foot panels of various kinds that I can take with me and set up together.

Fortunately there are no A/C outlets in the immediate vicinity of the mic location and if there were one I'd probably cover it and let the director sweat a bit!. I don't think wind across the mic itself will be a major problem, but I'll know more after Friday.

Hopefully I'll be abble to post a few before and after clips next week.

I recorded a rehearsal last night as a "dry run". Unfortunately, about 20% of the players were out for some reason or other, so we were not at our best, and were missing all but our bass trombonist, but I wanted to take a shot at it and see how bad the room really sounded.

Not great, but in some ways better than I had expected. I had to set up above and behind the director and was only a couple of feet from the wall. However, there were racks of those big exercise balls that you roll around on up against the wall and I think they helped a bit in so far as reflections off the wall.

I ran the clip through Sound Soap to filter out the A/C whoosh, but fortunately(?) compared to the sound of the band, the whoosh wasn't all that noticeable even when it was there.

Things I notice in the clip are "some" muddines in the bass (partly due to me being a "muddy sounding" tuba player, I guess) and a general lack of liveliness to the overall sound.

I left a few seconds of the director's normal speaking voice before and after the clip as a reference for loudness etc. Interestingly enough the voice sounds dead on. I think if you play it at a high enough level for the voice to sound natural, the band will be --- pretty loud!

Any and all comments and suggestions for improvement welcomed - at least those unrelated to the musical quality. We're all amateurs after all. Please don't suggest that we fire our tuba player!

Clip is a VBR Mpeg about 5MB

http://www.j-e-andrada.com/CPVBR.mp3

Jim, your initial post said that you thought you were okay for equipment, but I don't think you ever said what you were using. The mic in particular certainly has a bearing on the results. It's obviously a stereo mic or stereo array, but what make and model?

Also, the acoustics of the room are a lot different from what we are accustomed to in concert halls, and that has a lot to do with the perception of flatness. The reflected sound waves are not delayed as much as in a hall so you don't get the reverb effect, and more of the high frequencies have been absorbed out of the reflections. There's probably a limit to what you can do to combat that during the recording. But in post you can add some EQ, make several copies of the same track and use reduced levels (-6 dB or so) of copies staggered from the main one by plus and minus 30 milliseconds or so, and/or use your program's canned echo functions.

Sorry - should have said what I was using

It's an M/S array. Schoeps wide cardioid and figure 8 (Colette modular) into an SD 702. I've used the same setup for a bit of brass recording in better spaces and the sound in the bass was much crisper.

I was thinking to play with a couple of different configurations but from what I'm hearing I suspect the room is the main issue. Good news is that the recording as is is fine for the intended puropose of having the director pick apart the playing.

In spite of which, I'm trying to use this as a learning experience and "overachieve" a bit.

Room is roughly 24 feet wide and 40 feet long, 10' ceilings. Floor is commercial carpeting over concrete, walls are sort of standard strip mall construction (wallboard over wood or metal studs) The air conditioning duct runs below the ceiling so I'm guessing it is not a dropped ceiling, but actually the underside of the roof. Front door and walls (24' approx) are glass in aluninum frames. Band faces one of the long walls roughly in the middle of the long axis. Mics were slightly above and about 3 feet behind the conductor.

The space is normally a jazzercise studio and we get to use it for next to nothing. Which is about what our budget is!

We do a couple of concerets in churches later in the season and hopefully the acoustics will be much better

Thanks for the response.

Jim,

I think you've discovered the fundamental truth that a brass band is a pretty LOUD thing. And an air conditioning system is (comparatively) a pretty quiet thing.

The AC would be a much, much bigger issue if you were trying to record a solo picalo.

This is essentially why you aren't having great problems. Your SIGNAL is substantially overpowering your NOISE. Exactly what you want.

So I'd recommend you listen to your recordings with an ear to ensemble balance and dynamics and worry less about either the AC or the sound of the music rattling. IMO, they can be ignored if you're not recording for the ages.

Why on earth would anyone want to record a solo piccolo?????

Just kidding!!!! Although come to think of it a piccolo isn't exactly quiet - it would also probably put an A/C system to shame.

Of course you're right - a brass band isn't usually known for its subtle and delicate tonality.

After hearing the clip, I tend to agree that its the room. at first I thought something was wrong considering you were using schoeps microphones,( which have a great reputation for excellent sound.) then I heard the snare drum and there was the high end that everything else lacked. one question? how high was the microphone setup? and two.. how far from the back wall? can you get a boom to be able to place the mics well above the conductor? due to the limited space I think your high end is actually being eaten up by the players themselves. with that in mind I think the higher you get the more high end will return to the recording considering youre eliminating humans out of the way of the sound. as well as getting away from the wall. MS will still give you the (stereo effect)

Gerry,

Good thought re the height. That's something i can try next time.

The conductor is pretty short so I think the mic was about 6 feet high - I can probably get it up two or three feet more and see if anything changes.

Your description is pretty good - I think the bass is muddy and the highs lacking in brilliance, and I think both are due to the room and not the mics.

I've recorded tuba by itself in a better (although not perfect) space and it was nice and crisp with exactly the same setup, so I know the mic configuration is capable of really nice sound. I do plan to try a couple of different configurations next time though.

The cornets tend to face somewhat downward and I think some of their sound is being dulled by the carpeted concrete floor as well as the human sound absorbers.