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The 3:1 rule Condenser Microphones
Old 18th December 2011
  #1
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The 3:1 rule

This is something I should know by now but don't..
I know how to apply the rule on an "horizontal" micing of a source.
But does it work the same way "vertically" if you want maximal phase accuracy.

By that I mean, if the first mic is 1ft from the source and you want to place another one behind/further away, the same rule applies? ie 3ft from the first mic, 4ft from the source. Something tells me it doesn't..
Old 18th December 2011
  #2
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The 3:1 "rule" is generally measured from the source, left right, up down, doesn't matter. Just remember it is only a general rule, not a precision exercise. You may need to be 4:1, 5:1 or something else entirely to eliminate problems on some sources, and you may be able to get better results with closer spacing on others. Reflections can also be the source of the phase problem instead of the mic spacing relative to the source. In such cases the solution might be to move the whole enchilada (mics, source, everything together) to a different location in the room. I usually start with roughly a 3:1 spacing when dual micing, but usually wind up moving things around from there till they sound good.
Old 18th December 2011
  #3
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Yea but wouldnt my example above deviate from the rule since the second mic is 4ft from the source?
Old 18th December 2011
  #4
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Originally Posted by theBackwardsman View Post
Yea but wouldnt my example above deviate from the rule since the second mic is 4ft from the source?
I'm not quite grasping your question but, since you say you're hazy, just remember that the 3-to-1 rule of thumb is typically applied when you're multimiking a drum kit or other circumstance where you have multiple sources near each other and you want to minimize, for instance, the snare mic picking up the rack tom, which is also miked (which, when the mics are mixed together in a stereo mix, might produce phase-relationship-related comb filtering).

In that example, having the snare mic at least 3 times as far away from the rack tom as the tom's own mic means that the pickup of the tom by the snare mic will be no more than 1/9th as loud as the pickup of tom in its own mic -- greatly reducing the possible comb filtering problems.

EDIT: here's an explainer -- http://hyperphysics.phy-astr.gsu.edu...ic/invsqs.html -- and another -- http://hyperphysics.phy-astr.gsu.edu...isprob.html#c3

[Remember radiated energy decreases with the square of the distance from the source. So a second mic 3 times as far away from the source as the first mic will pick up about 1/9th as much sound, everything else being equal.]
Old 18th December 2011
  #5
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Quote:
Originally Posted by theBackwardsman View Post
Yea but wouldnt my example above deviate from the rule since the second mic is 4ft from the source?
I have always seen the "rule" worded as "the second mic should be at least 3 times the distance from the source as the first". Going with exactly 3:1 is not automatically better, and it might sound worse there. Or it might sound better at 2 and 1/2 feet depending on the source and the sound you are going for... As I said, it's not cast in stone and is generally used as a starting place only. If you were going to hard pan mics 1 and 2 left and right, the ultimate phase relationship would be effected just as much by the listener's position with regards to the speakers.
Old 18th December 2011
  #6
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I think the question is simpler than you think. Might be that english is not my native language that's making it more confusing.

The reason I'm asking is not to discuss the 3:1 rule itself but to see it same "rule" applies in my example:

Let's say you're micing an acoustic guitar.
Normally when describing the rule you'd put two mics equidistant from the source and the distance between the mics is supposed to be three times whatever the distance to the source is:
http://www.homestudiocorner.com/wp-c.../Picture-2.png

My question is, does the same rule apply when the mics are NOT equidistant to the source, say if first mic is 1ft from the source second should be 3ft from first mic = 4ft from source:
http://www.drivehq.com/file/df.aspx/...113/3to1_1.jpg

This is NOT for me to use as an absolute rule when recording so no need for lecturings, I will use my ears as usual. I still want to know the theory behind it. It's way better to have guidelines to tweak from.
Old 18th December 2011
  #7
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As I understand it, the "rule" is to have the second mic far enough from the first that any phasing is low enough to be inaudible. Geometrically, it makes no difference if it's sideways, upside down, or crossways.
Old 18th December 2011
  #8
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So it doesn't matter how far mic 2 is from the source as long as it's at least 3x away from the closest mic?
(summing up all your suggestions)
Old 18th December 2011
  #9
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Correct. The difference in the time it takes the sound to reach each mic will make any phasing inaudible. That's the theory, anyway!
Old 19th December 2011
  #10
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Originally Posted by Old Goat View Post
Correct. The difference in the time it takes the sound to reach each mic will make any phasing inaudible. That's the theory, anyway!
Actually, it's the logarithmic drop-off of amplitude as one gets farther away from the sound source that minimizes the effect of phase-mismatch induced comb filtering.

Radiated sound from a single point will diminish in a free field with the square of the distance. (This is true of light, magnetism and radiation, as well.)

If you have one radiative sound source (IOW, it's giving off equal sound in all directions), X, and two mics, A and B, and A is one foot from the source and B is 3 feet from the source (and there are no reflecting surfaces), the sound level at B will be 1/9th as loud as at A. When you combine A and B in a typical stereo drum mix, that should be enough to minimize comb filtering to an unobjectionable level.

EDIT: here's an explainer -- http://hyperphysics.phy-astr.gsu.edu...ic/invsqs.html -- and another -- http://hyperphysics.phy-astr.gsu.edu...isprob.html#c3


The three to one rule is typically only applied to multi-miked, multi-sound-source situations like miking a drum kit or perhaps spot miking a small acoustic ensemble.

When multi-miking an electric guitar cab, it's common to use a close mic and then a distant mic to pick up room reflections (as desired). Some phase-related comb filtering in such a situation may not be objectionable or might even be desirable.

OTOH, multi-miking an acoustic guitar, many people do attempt to keep the distance between the guitar and the mics equal from mic to mic -- however, this is complicated by the fact that the guitar sound does not radiate from a single point, but rather from the entire soundbox.
Old 19th December 2011
  #11
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Sorry, didn't mean to come off as "lecturing", My understanding is that the distance between the mics is not what is being measured, it is the distance to the source. It looks like the graphic you linked to is for controlling phase while evenly micing multiple sources like a symphony of choir. That is different than micing a single source like a guitar amp. Having the mics at different distances from a source is actually what you are going for, so you are good to go.
Old 19th December 2011
  #12
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Quote:
Originally Posted by theblue1 View Post
Actually, it's the logarithmic drop-off of amplitude as one gets farther away from the sound source that minimizes the effect of phase-mismatch induced comb filtering.
Which is what I meant, but you put it purtier, er, more eloquently



Quote:
OTOH, multi-miking an acoustic guitar, many people do attempt to keep the distance between the guitar and the mics equal from mic to mic -- however, this is complicated by the fact that the guitar sound does not radiate from a single point, but rather from the entire soundbox.
But that's probably how I can get away with one mic looking down at the neck/body, and one on the lower bout sounding pretty good.
Old 19th December 2011
  #13
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Quote:
Originally Posted by Go Nigel Go View Post
My understanding is that the distance between the mics is not what is being measured
Is this true? I have always been tought that it's the distance to the first mic..
Even with a single point source.
So you're saying the distance between the mics is irrelevant?

2 different versions of this now Who is right?
Old 19th December 2011
  #14
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mics that are equidistant from a snare end up having very good phase coherence no matter how far they are from eachother..in fact you could call that "in phase" for the purposes of this argument...the part that gets tricky is...

let's say that you really like getting the picture of your kit using your OHDS...meaning you'll be going for a whole kit type capture with a snare sound that you really like in the OHD tracks and most likely will be compressing a lot later....when you bring in the close snare mic, it will always be out of phase in some way with the OHDs...it then becomes a matter of what kind of phase cancellation that you like between the two
Old 19th December 2011
  #15
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Yea, drums is a different beast and that's why I chose an acoustic guitar as an example instead. Alot of people say that you should set up the mics equidistant from the sound hole and then the mics 3x the distance to the guitar itself apart from eachother. But this thread has introduced other suggestions..
Old 19th December 2011
  #16
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Quote:
Originally Posted by theBackwardsman View Post
I ...My question is, does the same rule apply when the mics are NOT equidistant to the source, say if first mic is 1ft from the source second should be 3ft from first mic = 4ft from source:
http://www.drivehq.com/file/df.aspx/...113/3to1_1.jpg

This is NOT for me to use as an absolute rule when recording so no need for lecturings, I will use my ears as usual. I still want to know the theory behind it. It's way better to have guidelines to tweak from.
It has little to no value in that application. All 3:1 is saying is use what ever distance between mics needed to attenuate pickup between the two so the out of phase effects are not heard as a problem.
In a close/far setup the far mic is indeed attenuated', but even that reasoning would fall apart if you decided to bring the level up on the second mic. What ever out of phase effect is strongest when the two are near equal levels.
Old 19th December 2011
  #17
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Quote:
Originally Posted by theBackwardsman View Post
Yea, drums is a different beast and that's why I chose an acoustic guitar as an example instead. Alot of people say that you should set up the mics equidistant from the sound hole and then the mics 3x the distance to the guitar itself apart from eachother. But this thread has introduced other suggestions..
As I understand it, the 3:1 rule doesn't really have anything to do with the distance between the two mics. The distance between mic A and mic B will have more to do with stereo separation than with phase coherence. The 3:1 rule just applies to the distance of each mic from the source, and has nothing to do with the distance between each microphone in use.
Old 19th December 2011
  #18
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Quote:
Originally Posted by Silent Sound View Post
As I understand it, the 3:1 rule doesn't really have anything to do with the distance between the two mics. The distance between mic A and mic B will have more to do with stereo separation than with phase coherence. The 3:1 rule just applies to the distance of each mic from the source, and has nothing to do with the distance between each microphone in use.
I think it does, in a case where 2 mics are equidistant from source. But seems like you're right in the other case.
Old 19th December 2011
  #19
Quote:
Originally Posted by theBackwardsman View Post
Is this true? I have always been tought that it's the distance to the first mic..
Even with a single point source.
So you're saying the distance between the mics is irrelevant?

2 different versions of this now Who is right?
The issue one is trying to deal with is the problem that results when you mix together two signals from mics that are different distances from the same sound source. (Of course, with drum miking, things get complicated quickly because you often have 8-12 or more sound sources and possibly as many mics -- or you may be doubling up some sound sources on a single mic at times.)

If the mics are different distances from a given source, when you mix those mic signals together, the signals from that sound source will combine to some extent in the mix and produce some level of comb filtering.

By keeping the ratio of distance between the source and 'target' mic and the source and the 'non-target' mic high, the rule of thumb being at least 1:3, because of the way radiating sound diminishes, the non-target mic should have something like 1/9th the pickup of the sound source that the target mic has.


By the way, it's easy to make syntax errors when discussing this... I caught myself about to type a phrase that could have been interpreted as contradicting what I was saying -- or at least confusing folks; the phrase I was about to use was 'the ratio between the two mics' -- which might have made it sound like I was talking about the distance between the two mics. In reality, what I meant was the ratio of the distance of mic A from the sound source and the distance between mic B and the sound source.
Old 19th December 2011
  #20
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Quote:
Originally Posted by Silent Sound View Post
As I understand it, the 3:1 rule doesn't really have anything to do with the distance between the two mics. The distance between mic A and mic B will have more to do with stereo separation than with phase coherence. The 3:1 rule just applies to the distance of each mic from the source, and has nothing to do with the distance between each microphone in use.
What's missing here (or often in these discussions) though is specifying whether you're talking about a stereo spaced pair -or micing two or more different sources.
In that first case you are looking at capturing a single image and the spread and position is intended to use phase in part for a desired stereo effect.
In the second case the goal is to attenuate destructive phase interference between multiple sources.
The case is made for 3:1 stereo placement’ as well but in my experience with equal distance to the source there’s quite a lot of latitude in the spread
-more flavor choices there mostly.
Old 19th December 2011
  #21
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The 3:1 rule can help to minimize bleed when two mics are used on two separate sources of similar volume in proximity to each other.

Re-read that, then read it again.

When following the rule, the two mics should be at least three times as far apart as the distance between either mic and its intended source. This keeps the bleed in either mic down about 9dB below the intended source, which is what one engineer decided one fateful day is an acceptable level of bleed to work with.

That's it.

Here is a great article on the subject: THE THREE TO ONE RULE & PHASE CANCELLATION FULLY EXPLAINED

The 3:1 rule does NOT prevent phase problems when using two microphones on one source. In fact, it almost guarantees problems.
Old 19th December 2011
  #22
I think the problem here is the original poster is looking at a close mic/ambient mic setup and is trying to apply the "3:1 rule" to it.

In those instances it may or may not apply since there is nothing else in the distant mic that needs to be dealt with.

For example, acoustic guitar...

If you have a close mic on the acoustic guitar and then an ambient mic on the acoustic guitar... you can try to follow the 3:1 rule but you don't absolutely have to. Since the ambient distant mic will be adjusted (volume, EQ, etc) in relation to the sound of the close mic.

Now... If you were recording Acoustic Guitar and Upright bass in the same room simultaneously... THEN the 3:1 rule starts to become more important.

In this scenario the distant mic to the acoustic guitar IS the close mic to the Upright bass. The distant mic to the upright bass IS the close mic to the acoustic guitar.

So you can't adjust the sound of the acoustic in the distant mic without effecting the sound of the Upright bass. Likewise, you can't adjust the sound of the upright bass in its close mic without effect the sound of the ambience of the acoustic guitar.

You can't turn the upright bass mic down to tame the ambience of the acoustic guitar, because you are then turning down the Upright Bass. You can't EQ out some top end or midrange or bass in the ambient guitar mic because you are now EQ'ing the Upright bass as well, and vice versa.

To keep this from being an issue, you want to make sure the close mics on EACH instrument are at least 3x's closer to their intended instrument than they are to the other instrument.

you see it's not "mic to mic". It's "Source to mic".
Source1 to Mic1=1 unit of distance.
Source1 to Mic2=3 units of distance.
Source2 to Mic1=3 units of distance.
Source2 to mic2=1 unit of distance.
Make sense?

When JUST micing a single instrument, the 3:1 rule isn't as important since you can adjust the distant mic to make it sound good after the fact. You can turn it down to get a little ambience but not enough to cause drastic phase interference with the close mic, you can EQ it, etc... Also the reverberant field verse vs close field comes into play... so depending on the size of the room, the 3:1 rule on a single instrument doesn't always have to be followed because the distant mic might end up being in the reverberant field anyway. And so on... That's why it's a "rule of thumb" or a "guideline" but not a hard and fast rule.

Also don't confuse the 3:1 rule with stereo mic'ing techniques. I see a lot of young kids do that as well. For stereo micing the 3:1 rule doesn't apply.
Old 19th December 2011
  #23
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Old 19th December 2011
  #24
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Originally Posted by theBackwardsman View Post
Thanks for that post, easy to understand!
Regarding the rule not applying to stereo micing, are you sure? Or is Mike Shipley one of the kids you mentioned MIKE SHIPLEY: Recording Alison Krauss' Paper Airplane
100% sure. If it did, then ORTF, Decca Trees and spaced pairs would never work.

think about it for a second... how can you space two mics in a stereo mic'ing technique 3x's the distance than they are to the source? You can't.

If one mic is 6ft away and the other mic is 18ft away, it just pans the sound to the closer mic.

In a stereo mic'ing technique, "center" is always equidistant to both mics. Panning comes from the difference in distance from one mic to the other.

I opened up the SOS article, but I'm not going to sit here and read through the whole thing to find the spot that is being mis-interpreted. Just one look at the 3rd pic down on the page shows "Most of the acoustic instruments on the album were tracked using spaced pairs of Neumann KM54 small diaphragm condenser mics." If he was trying to use the 3:1 rule they wouldn't be 6" apart in the pic.
Old 19th December 2011
  #25
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"The mic for the acoustic guitars, banjo, mandolin and Alison’s violin was pretty much the same: Neumann KM54 with 1:3 stereo miking principle: for every one inch away from the instrument, the mics should be three inches apart to keep the stereo image.
Most of the acoustic instruments on the album were tracked using spaced pairs of Neumann KM54 small?diaphragm condenser mics.
I knew that I wanted to have the acoustic instruments across the whole stereo spectrum and have lots of depth and feel, so I didn’t want to have just a mono source. "

Not trying to be an ass, but it was this article that made me think about different ways to apply the rule on acoustic guitar and that's why I started the thread
Old 19th December 2011
  #26
Quote:
Originally Posted by theBackwardsman View Post
"The mic for the acoustic guitars, banjo, mandolin and Alison’s violin was pretty much the same: Neumann KM54 with 1:3 stereo miking principle: for every one inch away from the instrument, the mics should be three inches apart to keep the stereo image.
Most of the acoustic instruments on the album were tracked using spaced pairs of Neumann KM54 small?diaphragm condenser mics.
I knew that I wanted to have the acoustic instruments across the whole stereo spectrum and have lots of depth and feel, so I didn’t want to have just a mono source. "

Not trying to be an ass, but it was this article that made me think about different ways to apply the rule on acoustic guitar and that's why I started the thread
OK... that has nothing to do with the actual 3:1 rule though. Here is the 3:1 rule...

Quote:
Two microphones, intended to pick up two sound sources must be placed apart at least three times the distance that either microphone is from it’s intended sound source.
What mike is doing with the 1:3 is trying to approximate keeping an equilateral triangle for the stereo pair...

Graph it and you'll see. Unfortunately though, mike's "rule" isn't perfect and doesn't give you an equilateral triangle, it gives you an isosceles triangle instead...

If you move out from the sound source by 1" and then split the mics 3" apart, what is the distance of each mic to the source? In geometry, the distance from the mic to the source would be the "hypotenuse".

So, make TWO right triangles, one to each mic (one for the left side and one for the right).

You know that side a of the right triangle is 1". You know that side b of the right triangle is 1.5" (half of the 3" span between mics). So following the Pythagorean Theorem of a^2 + b^2 = c^2... the distance from the mic to the source is 1.8".

Do the same thing if the mics were 2 inches out and 6 inches apart... The distance to each mic would be 3.6 inches

If the mics were 3 inches out and 9 inches apart... the distance to each mic would be 5.4 inches and so on...

But notice the mics are not 3x's the distance from the source than they are to each other. If the mics are 9" apart and 3"inches straight out from the source, they end up being 5.4" each away from the source. 9 is not 3x5.4.

This 1:3 that mike mentions really has no relevance. You can put the mics 9" away from the source and 3" away from each other. It doesn't matter. So long as both mics are the same distance from the source, there is no phase interference and no difference in the "sound" of the instrument. The distance between the mics in relation to the sound source only makes the pan feel "wider" or "narrower" when the musician moves around. That's it.
Old 19th December 2011
  #27
Quote:
Originally Posted by 2pulse View Post
The 3:1 rule can help to minimize bleed when two mics are used on two separate sources of similar volume in proximity to each other.

Re-read that, then read it again.

When following the rule, the two mics should be at least three times as far apart as the distance between either mic and its intended source. This keeps the bleed in either mic down about 9dB below the intended source, which is what one engineer decided one fateful day is an acceptable level of bleed to work with.

That's it.

Here is a great article on the subject: THE THREE TO ONE RULE & PHASE CANCELLATION FULLY EXPLAINED

The 3:1 rule does NOT prevent phase problems when using two microphones on one source. In fact, it almost guarantees problems.
I'd disagree about that article. He blows it right at the top by misstating the 'rule':
Quote:
"Two microphones, intended to pick up two sound sources must be placed apart at least three times the distance that either microphone is from it’s intended sound source."
Wrong.

It is the distance from each mic to the unintended sound source which should be at least 3 times the distance between that sound source and its intended mic. The distance between the mics themselves is totally irrelevant.

Really. Think about it. It's just a simple logic problem!

If one doesn't get it, it may be helpful to draw a diagram.

___________


I'm afraid you have a significant misunderstanding of the so-called 3-to-1 'rule' and the physics behind why it is often used as a rule of thumb in mic placement.

The distance between the mics is immaterial. (Feel free to read that several times.)

What is crucial is the ratio of the distance between a given mic and its intended source and the distance between that source and other mics that may inadvertently be picking up that source.

As long as that ratio is at least 3 to 1, the sound from that source entering the 'unintended pickup' mic will be at most 1/9th as loud (~20 dB lower CORRECTION: ~9.5 dB) as the sound picked up by the mic intended to pick up the source and, so, when those mics are combined in a mix, the comb filtering will presumably be less. (This presumes that the sound source truly radiates its sonic energy equally in all directions, which results in distance attenuation increasing with the square of the distance.) http://en.wikipedia.org/wiki/Inverse..._law#Acoustics

EDIT: here's an explainer -- http://hyperphysics.phy-astr.gsu.edu...ic/invsqs.html -- and another -- http://hyperphysics.phy-astr.gsu.edu...isprob.html#c3

Now, while we often simplify 3:1 'rule' explanations to the most primal elements -- two mics and one sound source -- we are really concerned with more complex situations like spot miking a multi-source situation -- typically a drum kit or a small acoustic ensemble. So the 'second' mic would actually be in the real world situation in order to pick up some other sound source -- which we've excluded from our example for simplicity sake; suffice it to say that that sound source will have a similar [but not equal] set of relationships with both the mic intended to pick it up and with other mics around it intended to pick up other sources.
Old 19th December 2011
  #28
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Quote:
Originally Posted by theblue1 View Post
It is the distance from each mic to the unintended sound source which should be at least 3 times the distance between that sound source and its intended mic. The distance between the mics themselves is totally irrelevant.
You're absolutely right about this, sorry to have confused matters.



Quote:
Now, while we often simplify 3:1 'rule' explanations to the most primal elements -- two mics and one sound source -- we are really concerned with more complex situations like spot miking a multi-source situation -- typically a drum kit or a small acoustic ensemble. So the 'second' mic would actually be in the real world situation in order to pick up some other sound source -- which we've excluded from our example for simplicity sake; suffice it to say that that sound source will have a similar [but not equal] set of relationships with both the mic intended to pick it up and with other mics around it intended to pick up other sources.
Most of the time when people talk about the 3:1 rule of "two mics on one source", it's presented as a cure-all for phase problems, e.g. that you can have your "3" mic just as loud as the "1" mic in a mix, and there won't be phase problems because of the magic ratio. I get it, you need to keep the distant mic's volume proportionately low, but I don't think this case even merits mention. With a single source, you can put your two mics ANYWHERE and have total control to lower the volume of one of the channels by however much you want.

How about that diagram:
Attached Thumbnails
The 3:1 rule-3-1-rule.gif  
Old 19th December 2011
  #29
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Before anyone jumps down my throat.... the above mic positions are only wrong if your goal is to follow the 3:1 rule, which would be putting the cart before the horse. Plenty of great recordings have been made in spite of it.
Old 19th December 2011
  #30
Quote:
Originally Posted by 2pulse View Post
You're absolutely right about this, sorry to have confused matters.
heh Could happen to anyone!

Hell I just confused myself just now, looking up the actual science to back up my practical understanding and, momentarily getting bogged down in inverse proportional math, the logarithmic dB scale and just lack of sufficient caffeine. Oddly, when I plugged away and worked through it, it all came out about right. So I didn't have to hurriedly go back and correct stuff. heh



Quote:
Most of the time when people talk about the 3:1 rule of "two mics on one source", it's presented as a cure-all for phase problems, e.g. that you can have your "3" mic just as loud as the "1" mic in a mix, and there won't be phase problems because of the magic ratio. I get it, you need to keep the distant mic's volume proportionately low, but I don't think this case even merits mention. With a single source, you can put your two mics ANYWHERE and have total control to lower the volume of one of the channels by however much you want.

How about that diagram:
Well, really, the 3:1 'rule' is best applied to multi-mic situations where any given mic is targeting one or more sources. And, of course, it's no cure-all, just some guidelines that will help minimize such problems.

When you're miking one source with multiple mics, it's good to keep those phase relationships in mind, but you may find yourself breaking the 'rules' to get a particular effect. Also, as noted, I think, many things we might initially think of as a 'single' sound source may actually radiate quite different sounds from different areas. Consider a grand piano or a stand up bass viol. They're big and different tones come from different parts of them. But the same principle also relates to an acoustic guitar -- or a violin. In fact, having miked single violins more than a couple times, I have a real appreciation for how different they can sound depending on where you're standing. (Of course, a violin is loud and will 'light up' a room pretty good, so 'early reflections' can be quite the issue.)


It's all pretty interesting stuff -- but it's pretty easy to get confused. And it's even easier, at times, to talk/write about it in such a fashion that your audience can get confused, even if you know how it all works.

That's why I'm a big believer in sketching this stuff out.

I remember when people first started talking about trying to time-align multiple mic setups in drum kits. I thought, OK, easy enough with a single sound source and two or more mics... but what happens when you have a bunch of sound sources and a bunch of mics? You time-align one pair of mics on one source and all of a sudden, everything else is farther out of whack. (And if one draws a diagram of a multi-miked drum kit and start scribbling in relative values, one will probably quickly be able to visualize the problem.)

A very different situation is represented by the common application of two or more mics to a relatively true single point sound source like a guitar amp. In that case, you can effectively time align the primary and secondary mics -- but you may actually end up loosing some of the 'effect' that you might like.
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