Professional Vocals Don't Have Mono Image!

  • Thread starter Thread starter Lionel_Hutz
  • Start date Start date
Most of the time when a singer is captured with 2 mics, they are one on top of the other. The same distance from the singer. I used to do this when I didn't have time to figure out what mic to use, sometimes I would end up using one for the verse and the other for the chorus. They could be using a vocal spreader. It could be a really short reverb. It could be a slight chorus. It most likely isn't 2 mics on the vocalist.
 
I agree, my idea now is that they move the one side of the stereo file behind a few millionths of a second or so. When I do that with my mono image stereo file vocal, the phase looks a lot similar to popular vocal recordings. Ex. Fuel by Metallica(starts of with just a single tracked dry vocal.)"Gimmie fuel, gimmie fire, gimmie that which I desire! Oooh!"
 
wait a sec, what's a vocal spreader do? are there brands out there?
 
i've lately started doing 2 mics on a vocalist in some cases. usually it's a dynamic and a condenser. i set them right on top of each other and have the singer "split the difference" when singing in real close--otherwise it doesn't matter much if the singer's back a foot or so.

there are times where i like getting the "best of both worlds" that a dynamic and LDC give you. i don't tend to spread them out, but i do tend to treat them differently (with effects), and between the two mics, i do tend to get a bit of a "fatter" vocal sound.

again, YMMV. :p

cheers,
wade
 
Lionel_Hutz said:
wait a sec, what's a vocal spreader do? are there brands out there?
A vocal spreader is a pitch shifting technique. You set the pitch 10 cents up on one side and 10 cents down on the other (for example) and set the pre delays, pan them wide and mix with the vocal. This is used for a lot of different things, Eddie Van Halen seems to have something like this on his rhythm sound on Poundcake. It ends up sounding like a chorus that doesn't sweep.
 
Lionel_Hutz said:
Yes, I've seen that mic placement done by professionals... I don't know the panning and/or other applications involved in blending the two mic's together so I guess I'll stick with offsetting the one side a millionth of a second or so...
Again, millionths of a second would not be noticable.

Milliseconds are thousands of seconds.
 
corban said:
A while ago I did a search on this site for the 3:1 rule because it didn't make sense to me for one source. I came up with people saying completely opposite things, but the arguments that made the most sense convinced me that it is for two sources, and that article confirms it. Maybe there should be a sticky on this site or something to counteract the bit of misinformation that is going around on that subject.
the 3:1 rule is for 2 mics, 1 source. It's for spaced pairs, wich is a STEREO coincident mic technique, get it? 1 source, 2mics-stereo. the reason for it is to reduce phase issues. Phase issues are inevitable when using more than one mic, even with one mic you got reflections (multiple arrivals), wich can cause phase issues as well. If you use more than one mic your studio will not blow up, just gotta be careful, usually phase is no big deal.
There are lots of stereo coincident mic techniques, Blumlein, xy, ortf, spaced pair, all these use 2 mics on 1 source, of course with xy you have no phase issues to worry about. There is also Decca tree mic technique wich uses 3 mics on 1 source, and 1 mic isn't even in line with the other 2. Also surround sound mic techniques, wich use 5 mics on 1 source.Even if phase is a prob, all you gotta do is move mics wich would be the simple thing to do, or use delay on a mic to compensate, or try the POLARITY REVERSE button on the console (wich is CALLED the phase button, but phase is a time relationship and that button has nothing to do with time, simply inverts polarity 180 degrees).
 
freak1c said:
the 3:1 rule is for 2 mics, 1 source. It's for spaced pairs, wich is a STEREO coincident mic technique, get it? 1 source, 2mics-stereo. the reason for it is to reduce phase issues. Phase issues are inevitable when using more than one mic

Sorry, despite you saying this is 101 material on the other thread, this is incorrect. It is not a rule for stereo micing, because when the stereo mics are panned, there is no phase cancellation. If the stereo mix is summed to mono, then phase issues may surface. That is why where mono-compatibility is important, coincident rather than near-coincident or spaced techniques are used.

The 3:1 rule is infrequently adhered to in stereo micing, even with spaced pairs. Think about recording a symphony orchestra with Decca tree: are the mics going to be three times further apart from each other than the orchestra is from the mics? No, that would be AB, not Decca tree.


even with one mic you got reflections (multiple arrivals), wich can cause phase issues as well

In a properly designed room, these reflections will be of substantially lower amplitude.

There are lots of stereo coincident mic techniques, Blumlein, xy, ortf, spaced pair, all these use 2 mics on 1 source, of course with xy you have no phase issues to worry about. There is also Decca tree mic technique wich uses 3 mics on 1 source, and 1 mic isn't even in line with the other 2. Also surround sound mic techniques, wich use 5 mics on 1 source.

Here you reject the 3:1 rule for stereo micing, after saying above that it is only applicable to stereo micing. The conclusion seems to be that the 3:1 rule has no value, but it does: for multiple mics on multiple sources.

Even if phase is a prob, all you gotta do is move mics wich would be the simple thing to do

Yes, you move them until the 3:1 rule is adhered to, or closely enough so.

or use delay on a mic to compensate

Doesn't work on multiple sources, since the relative delay times are different on each mic.

or try the POLARITY REVERSE button on the console (wich is CALLED the phase button, but phase is a time relationship and that button has nothing to do with time, simply inverts polarity 180 degrees).

Works rather poorly on complex sources. Useful for top/bottom head issues on drums.
 
yes, the 3:1 rule is for spaced pairs,not other stereo techniques, and yes, it's not really stereo, it's multiple mono.
and i was only talking about micing one source, not two, and all this only within the context of the 3:1 thing applying to spaced pairs.
yes, it's not a gospel rule either.
if what I said about 3:1 rule and spaced pairs is wrong then everything they taught at school about it is wrong and everything all those engineers told us about it is b.s., as well as everything in the books about it.
3:1 is specific to spaced pairs.
I'm sticking by what I said, and I'll take the word of those who taught me.
 
p.s.
was talking about using delay to compensate for multiple arrivals from one source, not 2.
and yes, I know you flip polarity on top and bottom snare, and the "phase reverse" button is only good for flipping exactly 180 degrees and will not necessarily fix phase problems. I've never used devices such as that one from little labs wich allows variability of how much polarity inversion happens.
with the "phase" buttons on consoles it's either 180 degrees or nothing.
 
who has a "properly tuned" room anyway?
 
Last edited:
freak1c said:
if what I said about 3:1 rule and spaced pairs is wrong then everything they taught at school about it is wrong and everything all those engineers told us about it is b.s., as well as everything in the books about it.
3:1 is specific to spaced pairs.
I'm sticking by what I said, and I'll take the word of those who taught me.
Take a chill pill. The only thing you missed is that the 3:1 rule is for micing two or more sources. It does not pertain to dual miking a single source. Recheck your books because you missed the point.
 
yes, however I never said anything about micing 2 sources, everything regarding spaced pair was about 1 source, 2 mics.
 
Last edited:
Dang it you guys are frustrating! You are misinterpretting this info:

"The distance between mics should be at least three times the mic-to-source distance (Again, see Figure 2). For example, if two mics are each 4 inches from their sound sources, the mics should be at least 12 inches apart to prevent phase cancellations."


To clarify, it should have been written like this:

"When stereo micing a single source using microphones in a spaced pair, the distance between mics should be at least three times the mic-to-source distance (Again, see Figure 2). For example, if two mics are each 4 inches from their sound sources, the mics should be at least 12 inches apart from each other to prevent phase cancellations; with the source directly between the mics."

Figure 2:

|mic|___________________________|mic|

______________(source)
 
my head is starting to hurt.

lets assume a sound eminates from a pulseateing orb (that eliminates some possible questions)

now how, if we assume that the mics are equally distant from the source, could it possibly make any differance if the mics are 3 feet apart or 8???

maby i've bene in here too long and i've just gotten stupid.

it's probably the stupid thing.
 
Reggie said:
"When stereo micing a single source using microphones in a spaced pair, the distance between mics should be at least three times the mic-to-source distance (Again, see Figure 2). For example, if two mics are each 4 inches from their sound sources, the mics should be at least 12 inches apart from each other to prevent phase cancellations; with the source directly between the mics."

Sorry, dude, that is absolutely incorrect.

It was correct and clear the way it was written. The 3:1 rule is not for two mics on a single source. Period.

Try stereo micing a 4-person vocal group from ten feet away, and your mics thirty feet apart. :rolleyes: Besides the fact that it would sound like shit, consider this:

Say you get the call to record, and figure out that ten feet away sounds great.

So you back up 10 feet, and spread your mics thirty feet, trying to follow the 3:1 rule.

Whoops. Now your mics are 20 feet from the source, and need to be 60 feet apart. Move them so they are 60 feet apart. Whoops, now they are 32 feet from the source, and need to be 96 feet apart. It's a never-ending loop.


It is physically impossible to apply the 3:1 rule to two mics on a single source. Think about it. If two mics are a foot away from a point directly between them, how can they also be three feet away from each other? The farthest they can ever be is two feet.

And it is unnecessary in any case.

If you put two mics on a single source, as long as they are equidistant from the source, there won't be any phase issues anyway, no matter how close they are to each other or far apart they are.
 
Last edited:
freak1c said:
bullshit..........

Edit:
Thank you for explaining in such detail. This, combined with another of your posts, has led me to a discovery. With all due respect, I believe you have a conceptual error.

freak1c said:
the 3:1 rule is for 2 mics, 1 source. It's for spaced pairs, wich is a STEREO coincident mic technique, get it? 1 source, 2mics-stereo. the reason for it is to reduce phase issues.

Here is where you are getting caught up.

A spaced pair stereo set up is not 2 mics on one source. Each side is treated as a seperate source, and the mics are placed so they don't pick up what the other side does, as much as possible. Therefore, the 3:1 rule is used as much as possible. So yes, in this one limited instance, 3:1 is for stereo.

But spaced pair is still not two mics on one source. It is two mics, on two sources, even if it is a single group of performers.

This is one of the drawbacks of the spaced pair. If you keep the mics far enough apart, you get a poor center image. Too close, and you get phase problems.
 
Last edited:
Back
Top