Drum Phase

[MoreSpaceEcho]

Maybe I'm simple minded, but I like to use a trusted setup on a well tuned kit and then listen to some drums and see if it sounds cool.

yeah. if i'm recording me i don't even bother to listen. i put up the mics, play for 20 seconds to make sure the levels are ok, and just start doing takes. at this point i pretty much know what i like and where the mics should go.

if i'm recording someone else, i have them play a beat and i listen with all the mics up. i'll check out the phase on the usual suspects (snare/overhead/floor tom), and generally things either sound good or they don't. if they don't i'll move or change the mics, or swap out drums or retune them.

drum mics being 180 out is no bigs, you just flip it. the art/potential for total clusterfuck is all in the in between phase relationships. sometimes the cancellation will kill you, other times you can use it to your advantage.

[losthighway]

Ok, I'll bite in hopes to advance the discussion. The 3:1 rule is either a semi-mystical belief, or a handy reference for beginners, based on the concept that detrimental phase cancellation won't happen if a second mic is 3 times further away from the source than the first.

In my experience this overused concept can prevent that incredibly intense phase cancellation where you wonder where all of the low frequencies or mids went, and then flip phase on a source and go "oh there it is." It does not prevent phase relationships from coloring the sound that you're hearing.

As I have suggested before, phase relationships with multiple mics are so complex that anyone mic'ing a drumset who thinks they have "everything in perfect phase" is kidding themselves.

[vxboogie]

go to home depot and get a pair of heavy duty ear protectors. do it asap. you don't want to be sitting in a room with a drummer without hearing protection, ever.

Ditto. I use a set of decent sealing ear buds(futuresonics atrios) with ear protectors over them. I figure I get about 50db of isolation with the pair. Best thing I've found in a one room setup.

[@?,*???&?]

3:1 rule of mic placement. It worked for me!

eta: bb-code hates me.

In general, yes, but the phantom center image is much more sensitive than that.

Do you guys even know what the 3:1 rule really is?

There was a recent discussion in which I simply bit my tongue.

I continue to bite my tongue.

Yeah Nick, I do. I even teach this stuff at a college. Hearing is believing. The 3:1 rule is simply a general guideline and is NOT precise. There's some great reading on the subject in this text if you'd like to learn more:

http://www.amazon.com/Sound-Recording-S ... 391&sr=1-1

[Nick Sevilla]

3:1 rule of mic placement. It worked for me!

eta: bb-code hates me.

In general, yes, but the phantom center image is much more sensitive than that.

Do you guys even know what the 3:1 rule really is?

There was a recent discussion in which I simply bit my tongue.

I continue to bite my tongue.

Yeah Nick, I do. I even teach this stuff at a college. Hearing is believing. The 3:1 rule is simply a general guideline and is NOT precise. There's some great reading on the subject in this text if you'd like to learn more:

http://www.amazon.com/Sound-Recording-S ... 391&sr=1-1

"SANITIZED FOR YOUR CONVENIENCE."

Cheers

[ashcat_lt]

3:1 rule of mic placement. It worked for me!

eta: bb-code hates me.

In general, yes, but the phantom center image is much more sensitive than that.

Do you guys even know what the 3:1 rule really is?

There was a recent discussion in which I simply bit my tongue.

I continue to bite my tongue.

The (at least) 3:1 rule (of thumb)

Better stated as the >9db guideline.

[chris harris]

If you're placing a spaced stereo pair 6 feet in front of a drumset, how do you apply the 3:1 rule?

[MoreSpaceEcho]

i've been putting a spaced stereo pair in the floor 6ft in front of the kit for years now and never thought about the 3:1 rule once. do i suck?

[eeldip]

yes. yes you do.

[MoreSpaceEcho]

quiet you!

[chris harris]

You're alright if the mics are 18' apart.

[drumsound]

i've been putting a spaced stereo pair in the floor 6ft in front of the kit for years now and never thought about the 3:1 rule once. do i suck?

[kRza.]

nice pic.

I knew this would open up a can of worms. Thanks for all the replies, i think. Okay voodoo masters, I'll give, what the fuck is 3:1?

To clarify: I am recording myself drumming, so can't do the listen while recording trick. I totally understand the math and logic of phase - have done this shit countless times, but what I'm after here is preventing the phase prob before mixing.
I've got a project starting soon & am going to try out several different combined micing tricks (mccarthy's Spoon snare trick, etc...), all of which mean adding extra mics that I don't normally use.

[Nick Sevilla]

nice pic.

I knew this would open up a can of worms. Thanks for all the replies, i think. Okay voodoo masters, I'll give, what the fuck is 3:1?

To clarify: I am recording myself drumming, so can't do the listen while recording trick. I totally understand the math and logic of phase - have done this shit countless times, but what I'm after here is preventing the phase prob before mixing.
I've got a project starting soon & am going to try out several different combined micing tricks (mccarthy's Spoon snare trick, etc...), all of which mean adding extra mics that I don't normally use.

3:1 rule was born eons ago.

It has to do with LEVELS. There will be here some who don't have a clue, and say it has to do with where the microphone is. This is the furthest thing from the 3:1 rule ever imaginable.

This is the rule, paraphrasing here so don't shoot me...

Your DIRECT SOUND SOURCE MUST BE 3 TIMES LOUDER THAN YOUR INDIRECT SOUND SOURCE.

In plain simple terms, the thing you are trying to record should be, AT LEAST, three times louder than anything else the microphone is hearing, ie background noise, room noise, another instrument, such as another tom, etc.

And, just for kicks, because I know someone is going to say I'm wrong, I will say it again, so I can be properly "ridiculed" :

The 3:1 rule has nothing to do with distances, only with levels.

Cheerio.

[ashcat_lt]

The (at least) 3:1 Rule (of thumb) is not mystical voodoo nonsense, but it is a poorly understood concept. The fun part is that it really has very little to do with distance. It's all about relative volume, which is why I think it's better termed the ">9db Guideline".

The real point is that phase cancellation is at its worst when you capture one sound source with two microphones at different distances and then mix them equally - matching the level of the direct sound. As you attenuate one of these signals, the peaks and dips in the phase induced comb filter get shallower, until they become negligible. This usually happens right around the point where there is about 9db difference between the two signals. That's the accepted standard, anyway.

Now, of course, volume drops off with distance. Without going through all the math, let's just accept the fact that it works out to where 3 times the distance equals a drop of 9db.

Take an omnidirectional mic and put it 3" off the snare, then take another perfectly matched mic and place it 9" away. Run them through matched pres set to exactly the same settings and bring them into two channels on a mixer. Run the fader for each channel up to the same mark and listen. You'll (theoretically) have no noticeable phase cancellation.

But, if you want to have more of the direct snare sound that you're picking up from that further away mic in the mix, and start to gain it up (at the pre or the mixer, or by turning the other down), you'll start to hear that comb filtering become a problem. This will get worse for a while, till the two direct signals are matched, then get better until you've got the distant mic 9db up from the close mic.

That's all there is to the "3:1 Rule" as applied to this phase issue. Period.


Edit - I was ninja'd, but I guess that's a +1!