How do room mic?


Is there some conventional wisdom to it? I know there is a lot of science behind it, and I understand the fundamental concepts; however, I fucking struggle with putting mics anywhere beyond a foot back from the speaker.

I am gonna do some experimenting today with the OM2 on the speaker (right off the grill aimed pretty dead center at the speaker just a bit off the dust cap) and the 990 all over the damn place. Any recommendations about where to start.

It's a fairly large room, and the amps are setup in one corner. The amps are:

Vox LNT -> HRD very open back cab w/ 2x10 Jensens = Flat against the wall with a corner ~4 ft. to the left and the other ~12 ft to the right. Opposite wall ~10 ft. back.

Tron Custom bAssman -> 2x12 closed back w/ WGS R60 (higher wattage V30 clone) and WGS BL80 (CL80 clone) = In the corner

Orange TT -> 1x12 w/ Hellatone 30 = Wall with corner ~4 ft. to the right and ~ 10ft. to the wall on the left.

Here is a very not drawn to scale idea of the room I am working with:






So should I consider putting all my amps flat against a wall (they would have another wall pretty damn close to their left, while having a lot of room to the right)?


Eh, I have no fucking idea what I am doing and/or talkin about. I am going to go mess around with mics for a bit ...

What do you want to get out of the room mic?

Personally, i generally only find close mics OR far mics useful. Mixing the two can be a fucking bugger. 90% of the time, i like really close ones. Occasionally i will go for one about three feet back.

If you are recording really clean loud guitars, some room can be a nice effect, but i actually generally find it easier, in my small spaces, to record close, and cheat the room with light reverb or delay.

In a smallish room, reflections off the walls can really screw up the EQ of the recording when you try to mix a close and far mic together.

I think Snaxo likes his room mics more though, see what he says.

I guess I am looking to fill out the brighter toanes of my amps (tron and LNT especially), and trying to get a little ... I hate figuring out toan words ... space? ... to the mix?

It is a smallish room, with a lot of shit in it though so I am sure reflections are running wild.

Really, my main goal is to just get better at recording Especially if I do some rough recordings with these bands. But I feel you, mixing close and room mics is really starting to become a pain in the ass. I feel like I will probably end up using reverbs and such as well.

The other option:


I have two completely empty bedrooms. They are somewhat smallish, but really solidly built with hardwood floors and no furniture. I could throw a rug under the LNT cab in there, and have a lot more flexability to play around with micing the room. Fuck, I might go do that now

The only negative is the rooms are right across the hallway from my roomie's quarters, but he isn't home all day so time is now.

There is troofs to this. I use a lot of them in place of reverbs; I've even thrown a stereo pair on a chorused-and-delayed bass guitar for effect.

I've found- not surprisingly- larger rooms are better for this sort of thing, and I tend to go the long way across the room with room mics. The easiest spearmint one could do, I think, would be to set up your cab & closeyclose mic (close enough you're not getting anything from the room, really) somewhere that sounds acoustically pleasing. I would go with the hardwood rooms if they're decently sized, probably. Then position a single mic on-axis with the cab, bust out a measuring tape, and go from there. Record a minute or two of jamming, move the mic back, repeat.

In a bigger room, what Mr. metalfanat1c did with the SDC pair in the corners can work really well. This was used a bunch on the Garda stuff, both on the guitars and on the big drum room in the studio.

With really big spaces, or drums, there are some tricks involved. There's a fairly recent issue of TapeOp that goes into the math behind the spacing to make drum rooms sound bigger or smaller than they are; I think it's the one with the Ross Robinson interview. I don't know if the article's available online. But the end result of it is that you can use Science! to trick the mics. It's not math heavy lifting; it's just proportions and ratios- distance from the source to the wall, distance from mics to the source, distance from mics to the wall sorta thing. It was meant for drums, but would probably apply to guitars as well.

Placing stuff near walls or (especially) in corners versus the center of the room or farther back from the wall will give you a different sound because of the reflections. You may or may not want this, depending. The general school of thought being that bigger, oddly shaped rooms work best.

Also, with the spare bedrooms: can you open the doors?

I am about to go in the spare bedrooms.

Yes I can open the doors. I think I might start with the cab centered on the wall, but a couple feet out so the open back gets a little breathing room. I'm going to follow your advice with the dynamic and on-axis LDC starting as far back as possible and repositioning the mic closer and closer.

Usually I record from the hallway to leave the room as empty as possible.

I'd pull the cab back from the wall myself as well. If that's how you're used to hearing it at volume, that might work, but the bass response is gonna be a fair bit different. If you really want to get stupid and have an extra mic kicking about, you could mic the back of the cab.