Checking phase between two PT tracks

[Unknown soldier]

I'm recording a guitar amp with a close mic and a room mic, and I blend the two tracks to taste in PT. I get a bit of the "hollow sound" when I bring up the room mic. So, I'm assuming there's a phase issue because of time differences between the two mics.

I've read about "nudging" one of the tracks to eliminate the phase issue. Is there a plug in or such that I can check the phase between two (or more) tracks? And is my goal to align them so they are completely in phase? I've heard bits and pieces about this situation, but not this question answered specifically.

thanks for any help!

[Ruudman]

Try PhaseTone by TriTone Digital.
RTAS plug in pluggo format.
Adjust to taste, reports (including mine) are that it can be a problemsolver.

There are also "inspector" plugs, but having phase issues because of mic placement/multiple mics is not compensated by nudging or using delay compensation.


ruudman

[Unknown soldier]

[QUOTE=
There are also "inspector" plugs, but having phase issues because of mic placement/multiple mics is not compensated by nudging or using delay compensation.


ruudman[/QUOTE]


So if using a room mic six inches from the grill and a room mic about 3 feet back, what can you do to avoid the hollow sound you get when combining them? I've EQ'd it out a bit and that helps, but that's a back end solution. What are some techniques to deal with this situation?

[Geert van den Berg]

Originally Posted by Ruudman

There are also "inspector" plugs, but having phase issues because of mic placement/multiple mics is not compensated by nudging or using delay compensation.

ruudman

What Ruudman says, but if you want to check the phase between 2 tracks, solo them, pan them hard left and right and watch them on a phase meter. You could download the free Inspector, or maybe you already did. But if you hear a hollow sound that already says enough. You can't align on a meter, it's just for verification.

You would need an IBP to fix the hollow sound if it's already recorded.

http://www.elementalaudio.com/produc...tor/index.html
http://www.littlelabs.com/ibpjr.html

[Geert van den Berg]

Also if one mic sounds better in the mix than 2 don't be afraid of using just one mic, maybe add some slight delay (make this track sound a little different, filter it different or use a coloring plugin) and pan those tracks to different sides. Or add a little of chamber reverb, if you have an impulse reverb, those sound usually pretty convincing.

[Unknown soldier]

I'm mostly using the close mic (sm57) and using a bit of the room mic (AT4050) to add a little depth to the dry, up front close mic. At some point the room mic mixed in becomes to much and it's obvious, and it sounds more like a live recording (and the hollow sound starts to kick in).

Maybe I need some pointers here. How do you guys deal with mixing close and distant mics without phase issues? the little labs box? Obviously it's done and done right. Obviously I don't know....

thanks

[PRobb]

The first thing would be to move the room mic a bit until it sounds better. If it's already recorded, use a plug with phase reverse, flip the phase an see which way sounds better. PT Time Adjuster has phase-or, technically, polarity- reverse. So do McDSP EQs. Or you could set the "nudge" to sample and advance the room mic until it tightens up.

[5down1up]

just have a look @ your waveforms .
the room mic starts later in comparison to your close mic .
nudge the room mic so it starts at the same point where the close mic starts .
( not the region , the waveform ! ) .
now zoom in and take a look again if both waveforms do the same " movement " . if one f.ex goes up and the other goes down , flip the phase on one of them .

make sure you have f.ex the trim tool on both tracks ( just sounds kinda different to my ears , if its just on one ? maybe it depends on the pt version ? )

now you have alligned the close mic and the room mic in phase .
if you want more room sound you can easily throw a short delay on the aligned room mic as well .

its better to record it right , but the method i am describing can most times FIX the problem , depending on what you are looking for ?

a cool idea for finding the right mic position , our beloved ecue mentioned , is to play a sine wave through the amp , set up your close mic , flip the phase on the next mic and try to find the place where it has the " most cancelation " , after that you flip the phase and this should be a cool starting point . ( well of course a sine wave isnt a guitar , but if your on your own , and ur running around in a rec room , wearing cans , and playing guitar with one hand and holding the micstand in the other , it gets kinda complicated )

good luck

[jpupo74]

Originally Posted by 5down1up

just have a look @ your waveforms .
the room mic starts later in comparison to your close mic .
nudge the room mic so it starts at the same point where the close mic starts .
( not the region , the waveform ! ) .
now zoom in and take a look again if both waveforms do the same " movement " . if one f.ex goes up and the other goes down , flip the phase on one of them .

make sure you have f.ex the trim tool on both tracks ( just sounds kinda different to my ears , if its just on one ? maybe it depends on the pt version ? )

now you have alligned the close mic and the room mic in phase .
if you want more room sound you can easily throw a short delay on the aligned room mic as well .

its better to record it right , but the method i am describing can most times FIX the problem , depending on what you are looking for ?

a cool idea for finding the right mic position , our beloved ecue mentioned , is to play a sine wave through the amp , set up your close mic , flip the phase on the next mic and try to find the place where it has the " most cancelation " , after that you flip the phase and this should be a cool starting point . ( well of course a sine wave isnt a guitar , but if your on your own , and ur running around in a rec room , wearing cans , and playing guitar with one hand and holding the micstand in the other , it gets kinda complicated )

good luck

Hi,

If you are going to do the whole sinewave stuff, I think It'll be better to try some pink noise...

For Phase problems this is what works for me:

Tab to transient on the close mic. Place the selector at the same location in your ambience mic track and tab to the transient hitting shift+tab. Hit delete in shuflle mode. This will line up your transients.


By the way, it's all a matter of taste.

Pupo

[Jason Poulin]

try placing your first mic where it sounds the best...

then if you think you'd like another mic, flip the phase on it and pull the patch chord out of your guitar and place it on something that will make a consistant buzz.

go in the room and move the mic (with headphones) where you hear the most cancellation. Once achieved, voila... flip phase again and you're in like flynn.

Good way to adjust tones with balancing the two together... try different positions too!



Jason