Reversing phase?

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dumass

New member
hey, when are you supposed to reverse the phase on drum tracks. i've already done it on kick and snare. should i do it to one of the overheads? also, do toms need to be reversed as well?
 
As a general rule it depends on which side of the drum the mics are facing. If you use the drummers position as your + reference then then any mics facing the tops of the drums should be + and any mics facing the bottom (like a kick mic in the drum, bottom tom mics or under snare mic) should be inverted.

You can use phase inversion to fix the OHs if there is a problem but with proper placement it shouldn't be neccessary.

Some engineers like to have the kick be positive and reverse everything else with the theory that it lets the bass move the speaker out on the transient instead of sucking it in.

Check your drum mixes in mono while you are setting up mics. If anything starts to dissapear or sound weird then you have some phase cancellation or combfiltering going on.
 
so i should take off the phase inversion on the top snare? my problem is that i have too much snare in my overheads and thats making my snare sound distant.
 
i've noticed that not all mics are wired the same and that causes the polarity to be inverted when you dont expect it......for instance, it seems as though audio technica and shure are opposite each other.

well i guess it could be the cables i was using last time i recorded, but i'm pretty sure i was using all the same brand of cables when i noticed. they were cheap cables though, so i guess the quality control could suck and they may have been wired so that some of them had the polarity reversed. either way, i've started looking at all of my tracks once they're on the computer and making sure they all match.

i guess what i'm saying is that you can see when the polarity is reversed, so just look and you'll know whether you need to flip it or not.
 
dumass said:
so i should take off the phase inversion on the top snare? my problem is that i have too much snare in my overheads and thats making my snare sound distant.
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It sounds distant when the phase is normal? If it sounds better inverted then go for it. Those are the things you need to listen for while tracking.
 
One trick that I use to test for phase issues is to start with the overheads first (since they are picking up the majority of the kit).

Then bring in each other channel separately and try reversing the phase on that channel. Choose the version that sounds the least "hollow" or has the most bottom end.
 
dumass said:
so i should take off the phase inversion on the top snare? my problem is that i have too much snare in my overheads and thats making my snare sound distant.
Click to expand...

I'd take it then you're not wanting or using the O/H's to get the whole kit.
Either way, just think of the phase of each mic in combination as a tone (and 'distance' in your case with the snare) option. The 180 deg flip is never going to be completly right or wrong (it also doesn't fix the time related effects), but different combinations of what tones get pushed and cut.
Good example; I mic my snare from the side. It's rotated 90 deg. re. the kit mics. Phase is +/- 180...
:D
Wayne
 
yea, i mic my snare from the side too, in this drum track. but the problem is, theres a lot of snare on the overhead track...and obviously, the snare sounds pretty distant on that. so if i lower the overhead track, then i loose cymbals. im gonna go with the eqing, but i dont wanna kill the natural sound of the cymbals too much.
 
dumass said:
yea, i mic my snare from the side too, in this drum track. but the problem is, theres a lot of snare on the overhead track...and obviously, the snare sounds pretty distant on that. so if i lower the overhead track, then i loose cymbals. im gonna go with the eqing, but i dont wanna kill the natural sound of the cymbals too much.
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Try compressing the overhead track in order to lower the volume of the snare hits relative to the cymbals. You should then be able to bring this to where it's needed.
 
TexRoadkill said:
As a general rule it depends on which side of the drum the mics are facing. If you use the drummers position as your + reference then then any mics facing the tops of the drums should be + and any mics facing the bottom (like a kick mic in the drum, bottom tom mics or under snare mic) should be inverted.
Click to expand...

Are you ALWAYS supposed to do this? I never have inverted the phase on the kick :(
 
masteringhouse said:
Try compressing the overhead track in order to lower the volume of the snare hits relative to the cymbals. You should then be able to bring this to where it's needed.
Click to expand...

how should i set the attack and release for that?
 
assume the mics and cables are all wired correctly...

when two mics record the same sound source and are basically pointing at each other, then a phase reversal MAY be warranted.

you CANNOT fix a problem in the overheads by reversing one mic's phase... you MAY benefit by adjusting one mic's time relationship to the other which is kind of what phase reversal does, but using phase reversal is a different intent. it's better to fix this before recording by using a technique like RecorderMan's suggestion (modified spaced mics), or some other.

compressing overheads to lower the snare in relation to the cymbals is very difficult... this is fix it in the mix. it may be a good exercise to learn by, but IMO you'll not be satisfied. a much better solution is to position the overhead mics to fix or minimize the problem. if you position the overheads better, the snare problem should go away and the balance will be much better.

on my kit I reverse every mic but the overheads because all close mics are on the bottoms and inside the kick... therefore all mics are on the opposite side of the source that the overheads see. it's a call whether to invert the overheads or the other mics.
 
dumass said:
how should i set the attack and release for that?
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fast attack, short release. The idea is to get rid of the transient portion of the audio envelope.

BTW this is an old trick that I learned by reading an article from Pete Townshend of the Who.

Mic position is VERY important as well, however my opinion is that the overheads should include the entire kit. If you close mike cymbals to get rid of the imbalance, stick a mic (or multiple mics) on every drum for better isolation, etc. you are introducing more phasing issues than if you stick with a minimum number of mics on the kit.

You should be able to get a great drum sound with 1-2 overheads, snare, kick, and room mics especially if you want that "old school" sound. I've even done a few sessions with 1 mic for an effect.
 
dumass said:
how should i set the attack and release for that?
Click to expand...

Instead of trying to assume a setting, how about just some general stuff?
A very fast attack and release will start grabbing the actual peak levels first and technicaly be the most accurate level control, but might leave the body of the snare remaining and a mushy snare tone.
Extending release begins to grab the body also.
Extending the attack a bit could allow some snap through, while still telling our ears the snare has been pulled back some.

Or perhaps go for more of the snare from the kit mics and rely less on the snare track?
Happy hunting.
 
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