reamping stereo phase problem

[FALKEN]

yo,

before i look like i'm beating a dead horse to death, i've been working on this all day and did some searches and tried some stuff and i'm still left flat.

I have a synth recorded on tape and I want to make it stereo sounding...

I tried various delays an panning and the result was less than great.

so I've been sending out the DI'd signal to a PA amp (and I also tried a guitar/keybaords amp) and I've been miking up the pa speaker(s) with a pair of mics. I've tried 57's, 635as, CAD 95's, and even mis-matched mics. I've tried spacing out the speakers, i've tried using only one speaker. I've tried setting up the speakers facing each other...

all of the above scenarious resulted in this strange thing...

when panned center, the tracks are loud, but when panned wide, they start to phase cancel.

what?????


isn't it supposed to be the exact opposite??

sometimes I've gotten mic placement such that when I phase reverse one side, and they are both panned center, the synth completely dissapears. still, when panning these tracks wide, they lose volume (when not phase reversed)

This is going to be bad if it ever gets played in mono. the synth volume will be out of control!!

I've tried almost everything.....

any suggestions???

[petermiller]

are you blending the reamp signal in with the original? and are you keeping the L R relationship intact from source to end product.

[Farview]

When you take two copies of a mono signal and pan them center, it will be louder than when they are panned wide. When that happens, you know that you have mono.

To make key stereo, I either:
A. run it through a dual pitch shifter, set 10 cents up on one side and 10 cents down on the other.
or
B. run it through a dual delay, set for 16ms on one side and 32ms on the other.
or
C. both (using the pre delay on the pitch shifter) set the longer delay on the side that is flat.


Mix the effected signal with the dry.

[FALKEN]

no, i am not currently blending the original in. I am running the track through a gate, eq, then to the pa, where it is double mic'd, back to the board, for panning. this gave me a thought though...if I were to phase reverse the original, and bring it up in the center, I might be able to even out the mono volume against the panned. maybe?

[Farview]

I'm not explaining myself very well. If it's louder panned to the center, it's mono, not stereo. Micing it through the PA isn't giving it a stereo spread at all.

[Farview]

If you reverse the phase of what you have and pan it center, it will disappear.

[giraffe]

what program are you useing?

some times there is a preference setting that that dictates that when panned wide the signal should be either 0, +3, or +6 db louder to make up for the fact that some thing coming out of both speakers is exactly twice as loud as something coming out of one speaker.

[giraffe]

Originally Posted by Farview

I'm not explaining myself very well. If it's louder panned to the center, it's mono, not stereo. Micing it through the PA isn't giving it a stereo spread at all.

and like he said, probably not stereo, or at least not meaningfully so.

[FALKEN]

i think it is me that is not explaining well...

no program...using an outboard mixer. mic'ing the pa HAS to give a stereo signal because its done with guitars all the time, right?? although I suppose that the signal is 'mostly' mono and 'somewhat' stereo, which is why I came up with the idea of phasing out the center, to make it 'less' mono and 'more' stereo....no? is there something else that I can do?

[Farview]

Originally Posted by FALKEN

mic'ing the pa HAS to give a stereo signal because its done with guitars all the time, right??

That isn't what reamping is. Reamping is taking a clean guitar signal and running it through a guitar amp and micing that up. It's used to change the guitar tone, not create stereo.

Doing what you are doing is only going to add a room sound to the mono keys. If you are close micing the PA, it won't even do that. It would be easier to put a reverb on it. (because that is all you are accomplishing)

Originally Posted by FALKEN

although I suppose that the signal is 'mostly' mono and 'somewhat' stereo, which is why I came up with the idea of phasing out the center, to make it 'less' mono and 'more' stereo....no?

The center is all you have. If you phase it out, it will dissapear. (in mono)

Originally Posted by FALKEN

is there something else that I can do?

Originally Posted by farview

To make key stereo, I either:
A. run it through a dual pitch shifter, set 10 cents up on one side and 10 cents down on the other.
or
B. run it through a dual delay, set for 16ms on one side and 32ms on the other.
or
C. both (using the pre delay on the pitch shifter) set the longer delay on the side that is flat.

You could do what most keyboard manufacturers do and just put a chorus on it.

[FALKEN]

ok ok wait a minute.

how in the heck is re-amping a part any different from playing a guitar through an amp? I mean, shit, an electric guitar is *mono*...and you can mic a guitar amp in stereo...I don't see how you say you can't do this with a synth??

like I said I tried those other menthods before posting and they sucked ass.

thanks.

[SouthSIDE Glen]

I guess what I'm not sure of is just what you're looking to do/accomplish with the "stereo" guitar. It is, after all, a mono source no matter how many mics you put on the cab. It's still one guitar/one amplifier/one cabinet.

If you're looking to make it stereo, you have three choices as to the "type" of stereo you're looking for:

1.) Natural stereo - here, it's not so much the instrument in stereo as it is the room in stereo. This would involve some form of distant miking in addition to the close miking. This could also be synthed with a stereo reverb.

2.) Synthesized effect - this would require splitting the mono signal into two identical mono tracks, panning them, and then effecting them through the use of differential EQ, delay, chorusing. Sometimes a stereo expander/phase trick bag can be added as well.

3.) Line doubling - playing the same guitar part twice and panning the two tracks to either side of center and letting the natural variations in performance provide the stereo seperation.

And of course any combination of the above can be used.

Of course you already know all that, I'm just highlighting the choices as a way to try and figure out just what you are looking for. Double-miking the cab is really little more than trying to get a natural differential EQ via mic technique instead of artificial EQ. Not super-effective all by itself when trying to go stereo unless one also throws a phase-based expander on it as well (not my favorite technique, but there's no accounting for my taste ).

G.

[Farview]

You can't get a stereo guitar (or anything) from micing a mono source. All you get is a mono source with stereo room ambience. If your room isn't all that great, the ambience won't be either. A reverb would be the way to go in that instance.

[brendandwyer]

the only way to get a stereo guitar track would be to have two speaker cabinets connected to your head, seperating them by some distance and micing both, correct?

[SouthSIDE Glen]

Originally Posted by brendandwyer

the only way to get a stereo guitar track would be to have two speaker cabinets connected to your head, seperating them by some distance and micing both, correct?

That's still really a mono signal just miked twice. The only advantage to that is to take advantage of the different timbres of the different cabs. Good for combining into a fat mono sound, just like double-miking a single cab. But it still doesn't really do much on terms of creating an actual stereo signal.

Edit: If the two cabs were put an a room and the room were distance miked, then one could get a stereo verb out of it. But like Jay said, that requires a good-sounding room. Artificial verb applied to those would often be more effective.

G.

[Farview]

Originally Posted by brendandwyer

the only way to get a stereo guitar track would be to have two speaker cabinets connected to your head, seperating them by some distance and micing both, correct?

What Glenn said.

If you have two of the same thing, it's still mono.

If you close mic two cabs fed by the same amp and the cabs are a mile apart (assuming the head is in the middle), you would still have mono.

[FALKEN]

what the crap.

I suppose then that mic'ing an acoustic guitar in stereo is also futile, since the signal is inherently "mono". ?? this doesn't make any sense.

also, why would two mono sources be louder panned center than to the sides? the volume should be identical. what am I missing?

[Farview]

Originally Posted by FALKEN

I suppose then that mic'ing an acoustic guitar in stereo is also futile, since the signal is inherently "mono". ?? this doesn't make any sense.

No, it isn't. Because different tones come out of different parts of the instrument. There is also a difference in the timing of the frequencies hitting both mics. (the boominess hits the mic on the body before it hits the mic on the neck) This creates a stereo image. With an electric guitar, the same thing is coming out of each speaker. So close micing multiple versions of the same thing will just give you the same thing you would get if you just copied the track.

Originally Posted by FALKEN

also, why would two mono sources be louder panned center than to the sides? the volume should be identical. what am I missing?

When you pan them to the center (on top of each other) the energy adds together. It should be 6db louder. If you had 16 tracks of the same thing, all coming in to your board at 0db with all the fader set at unity gain, your master meter would be pegged. It all adds up.

[FALKEN]

ok...

i have heard a single guitar mic'd in stereo on MANY recordings...there has to be a way!!

[Farview]

Either he was running through 2 amps (with different processing) or there was a close mic and a far mic (panned) or something like that. Close micing two cabinets with the same signal going to them will not get you stereo.


To better explain the acoustic guitar thing: If you get close enough, an acoustic guitar is a stereo intrument. If you put your head between the speakers on a 4x12, you will not hear stereo.

[FALKEN]

well I have had success with this once... on one speaker was a uher m537 straight on the cone and the other speaker was a sm57 hanging down in front of the speaker...gave a nice stereo spread.... but with this synth its just not happening.... I mean...if I pan the sides maybe 30% it sounds pretty good but any more than that i just start to lose volume like crazy. I'm probably just going to leave it at 30% i guess.... but this part sounds WAY better in the mix after going through a speaker and a dynamic mic... so I am going to pursue this method until its as good as it gets i guess.

[brendandwyer]

so, then....how do you do stereo guitar?

[Farview]

Originally Posted by brendandwyer

so, then....how do you do stereo guitar?

play it twice.

[SouthSIDE Glen]

Originally Posted by FALKEN

also, why would two mono sources be louder panned center than to the sides? the volume should be identical. what am I missing?

A lot there also depends upon the tupe of panning math the editor uses. It's not necessarily the same thing from editor to editor. Craig Anderton has an excellent article on this in his column on the EQ magazine website (www.eqmag.com).

G.

[SouthSIDE Glen]

Originally Posted by brendandwyer

so, then....how do you do stereo guitar?

See post #12 again .

G.