Cardioid room mics --- Do you Add EQ for bottom end fatness?

[Jules]

For drums - I point mine at walls (about 6 inches - 1 foot away) with the back of the capsule facing the kit. I usually get plenty of low end in mine.. often too much kick drum 'woof' & not enough snare 'crack' as I would like..

[Blast9]

LOL --- "woof" is perfect. I guess its down to the freq response of the mics. I remember your 149s being very meaty in the lowend (and your ribbon mics) I definitely need more:

[seaneldon]

it depends on the room and the kit and yadda yadda yadda, but...

if you've got your room mics out far enough, the low end frequencies have enough time to fully develop. you should get plenty of low end with the right mic and right placement.

[Blast9]

I see... So this is independent of proximity effect. Could theefore be phase cancellation, although what my ears hear is definitely not thin or lacking in bottom end.

[Musiclab]

What's important is to understand how the room mics work in the drum sound.
You usually don't want alot of bottom from the room you wan't it for the air and brightness. I usually hpf the room mics, usually I use figure 8 pattern. If you get fat bottomed room sounds by the time you mix in the rest of the kit you got mud

[Blast9]

OK gotcha... I was thinking more in terms of the room mics thickening the attack and brightness of the over heads and/or closer mics. (I guess thats where the hi pass comes in, with the natural "band pass" effect of more distant mics --- More emphasis towards lower mids and mids)

[John Suitcase]

I was lying in bed last night thinking about this...

If your kick has a fundamental tone of about 60hz, and the speed of sound is about 1100 feet/second, then each wave is about 18 feet long. So, at 9 feet, you'd be about 180º out of phase with a close kick mic. At 18 feet, you're 360º, which is like being in phase.

So, at 9 feet, you're not going to hear much low end.

Of course, you're high frequencies are more sensitive to the time delay, a 18 millisecond delay might sound funky, espeically on faster drum parts. You'd also likely want a tighter kick sound on fast material.

So, if you're recording something slowish, with a tempo in the 100 bpm range, I'd go for the big bottom room at 18 feet or so. If you're doing fast punk or metal, get the room in closer, and jsut worry about getting that bright attack that others referred to.

On a related note: What are you guys trying to get out of your room mics. If you just solo'd the room mics, what are you hearing? Is it clear? It seems my rooms often sound brassy, trashy, just kind of ugly. But I'm often working in less than ideal rooms, too.

Do you use your best mics and pres for the room (I've read a few approach this way)? I usually use a condenser, not my best, through a pre that I have available, usually an open channel on my mixer...

[John Suitcase]

Also, I wanted to point out that you can't hear phase cancellation in the room. It only makes itself apparent when two or more signals are combined into one mono signal, via a mic, or processing, or at the speaker...

[rwhitney]

I don't think I ever boost lows on cardioid room mics. Maybe I'll roll some off, though.

[Worlez]

I'm wondering the same things as Mr Suitcase - I'm going to be moving drum sessions from the smaller drum room into our large room as of tomorrow (when we have built our gobo's) and its going to open up all sorts of room micing possibilities.

Mono, stereo, omni, figure 8, coincident? Should be fun!

RE phase cancellation - you could get this in the room from reflections from the walls causing nulls at various points in the room couldnt you?

Al

[John Suitcase]

Originally Posted by Worlez

RE phase cancellation - you could get this in the room from reflections from the walls causing nulls at various points in the room couldnt you?

Al

I would imagine that would be the case, but with a cardioid, it's likely t be less of an issue than with an omni, I would suspect. The reflected sound should be lower enough in level relative to the direct sound so as not to be a major issue. Of course, if sound bounces off of several surfaces and happens to travel the same distance, it could refocus at the mic, causing enough level to cause problems...

I like the idea of plugging one ear and walking around 'til you hear the sound you're after. I don't know that using only one ear is quite the same as using a mic, but it should get you close.

If you know what you're listening for, that is!

[Brad McGowan]

One thing to keep in mind is that there will be dips and peaks in the low end response of your room. One very big reason why you may experience a lack of low end in certain spots in the room is because of the comb filtering in the low end. See the Realtraps site for articles on this subject. If you have a well treated room then you will find that things will be more even around the room. I've definitely noticed sweet spots in my room where the balance of lows to highs is really good and it's in those spots where the kick and snare have the best impact. I typically find that using large diaphragm condenser mics gives me a really trashy room sound that is overly bright. Using ribbon mics seems to smooth things out. Although those $5 Karma mini's work rather well. I'm also finding that SM57's sound pretty awesome as room mics in my room and add just the right mojo to the midrange. I have sometimes added a low shelf to room mics to restore the girth...especially on the condensers.

In my room one side is reflective with lots of diffusors. I usually set up the drums on this side of the room. When I put the room mics on the opposite side of the room I get a nice diffuse sound being picked up by the mics. I should try putting a cardioid mic a couple feet in front of the kit but facing away toward the far wall...I bet that would sound good since all the diffuse sound would have time to bounce around a bit.

Brad