Phase

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NU-TRA
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Phase

Post by NU-TRA » Fri Aug 04, 2006 1:47 pm

I just started testing out all my mics on my kit and noticed that I had to flip phase on the top of my snare vs. the bottom. Has this happened to you guys before?

V

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Post by seaneldon » Fri Aug 04, 2006 2:02 pm

that's physics. you don't HAVE to do that, but if you want it to sound right, you SHOULD.

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Post by NU-TRA » Fri Aug 04, 2006 2:21 pm

Cool I't always been the reverse for me. I usually flip the bottom. but that stays untouched. I think my floor tom top mic needs to be flipped.

V

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Post by seaneldon » Fri Aug 04, 2006 2:23 pm

oh i just reread your post. flipping the top mic? eh, not so typical. you generally "need" to flip the microphone that's facing the opposite direction of the other mics. if you're micing every drum from the top at a similar angle, a bottom snare mic will be out of phase, almost 180 degrees.

check your drums in one speaker mono and try again.

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Post by Mark Alan Miller » Fri Aug 04, 2006 2:46 pm

Filpping the top vs the bottom's polarity should be decided in context with the other mics in the kit. For example, it might make more sense to flip the top relative to the overheads...
And don't assume that all of your mics are wired with the same polarity, either - so check them all and get to know 'em!
he took a duck in the face at two and hundred fifty knots.

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Post by Brett Siler » Fri Aug 04, 2006 2:54 pm

Mark Alan Miller wrote: And don't assume that all of your mics are wired with the same polarity, either - so check them all and get to know 'em!
True. For example I have two Oktava 319's that have opposite polarity. If I use them for stereo overheads one is out of phase from the the other!

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Post by drumsound » Fri Aug 04, 2006 4:34 pm

I like to check and make sure my overheads work together and check all the other mics to them. If I'm using two mics on one source (BD for example) I just list to those two and make sure they are phase coherent to each other, then I check them to the OH. So If I just listen to the inside and outside BD and one needs to be flipped for the best sound, when I'm checking to the OH I hit the phase button on both of the BD mics at the same time to listen to the effect it has on the OH/whole sound.

I'm always thinking of the whole instrument that is the drum-set.

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Post by RodC » Fri Aug 04, 2006 4:46 pm

If you are using a DAW learn how to zoom way in and examine each of tracks, side by side. You can then see the phase of each mic and then pick which tracks to move/Invert.
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Post by NU-TRA » Fri Aug 04, 2006 5:35 pm

Yeah i'm gonna check and see if cables were soldered incorrectly. My over heads are about 3 feet wide and 18 inches above the kit slighty pointing away from each other. I might have to go for the XY method or the near coincident pair style. I'm using those peluso cemc6 things. They sound pretty nice.

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Post by Jon Nolan » Fri Aug 04, 2006 5:35 pm

Mark Alan Miller wrote:Filpping the top vs the bottom's polarity should be decided in context with the other mics in the kit. For example, it might make more sense to flip the top relative to the overheads...
And don't assume that all of your mics are wired with the same polarity, either - so check them all and get to know 'em!
can you explain this a little more please mark? i am still pretty new, and i didn't even know that different mics have different polarities(!). or maybe i do, but don';t understand it this way.

in the above scenario though - are you suggesting that it might make more sense to flip the top snare mic b/c of it's potentially problematic phase relation ship to the OH's? if it doesn't have any phase issues with the OH's, would it generally be better to flip the bottom then? if so, why. feel free to wax on about phase a bit if you desire. i'm all ears (or, eyes).

i guess i'm just trying to expand my understanding of phase - trying to wrap my little 40 watt noggin around it conceptually.

thanks in advance...
Jon

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Post by RodC » Fri Aug 04, 2006 7:35 pm

Here is some screen shots that compair the OH Kick and Snare. This is the simplest example.

Most examples show a nice sine wave, this is some real world examples.

http://www.beyondsanityproductions.com/DrumPhase.html

You can read the captions for explaniations.
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Mark Alan Miller
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Post by Mark Alan Miller » Fri Aug 04, 2006 9:13 pm

Jon-
Well, mics can be wired so a compression at the diaphragm yeilds a positive or negative going voltage. Generally, if I recall correctly, a compression should yeild a positive voltage, and a rarefaction a negative one. All it takes is to flip the 'hot
and 'cold' conductors on the mic to invert this. I've had it happen accidentally when someone does a repair on one of my mics, for example. Also, I've had it happen where a mic (of which I own three of the same model) is wired with the opposite polarity at the factory.

On the issue of polarity of the top and bottom snare relative to each other, and to other mics on the kit (overheads, for example) different conditons might apply depending on mic choice (and their resulting polarity) along with placement.
Start by comparing the top snare mic to the overheads. Listen to the sound of them at roughly the same volume level, then flip the polarity of the top snare mic. If it sounds fuller and thicker not flipped, leave it not flipped. If not, well, flip it.
Then look at the bottom snare relative to the top, and select the polarity that sounds best to you.
Then, look at other mics in the kit relative to the overheads. See what you get.
I suggest that if you find yourself flipping the polarity of a lot of mics in the kit relative to the overheads, that it's better to simply flip the overheads' polarity.

Is that helpful? I hope so. I'd be happy to elaborate more if need be. :)
he took a duck in the face at two and hundred fifty knots.

http://www.radio-valkyrie.com/ao/aoindex.htm - download the new record (free is an option!) or get it on CD.

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Jon Nolan
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Post by Jon Nolan » Sat Aug 05, 2006 6:42 am

And don't assume that all of your mics are wired with the same polarity, either - so check them all and get to know 'em!
basically, if i understand right, a mic wired with a reverse polarity is wired wrong, right? there aren't mics that come that way are there? this was the sentence from your original post that confused me i guess.
On the issue of polarity of the top and bottom snare relative to each other, and to other mics on the kit (overheads, for example) different conditons might apply depending on mic choice (and their resulting polarity) along with placement.
Start by comparing the top snare mic to the overheads. Listen to the sound of them at roughly the same volume level, then flip the polarity of the top snare mic. If it sounds fuller and thicker not flipped, leave it not flipped. If not, well, flip it.
Then look at the bottom snare relative to the top, and select the polarity that sounds best to you.
Then, look at other mics in the kit relative to the overheads. See what you get.
I suggest that if you find yourself flipping the polarity of a lot of mics in the kit relative to the overheads, that it's better to simply flip the overheads' polarity.

Is that helpful? I hope so. I'd be happy to elaborate more if need be. :)
rod/mark, thx for the posts on this. i do appreciate it! :) i think i must have imagined that you guys were talking about something else i hadn't learned yet (beyond the question istill have above). i do know about flipping on mics and flipping polarity switches to check for phase relationships, though i am new and i do appreciate your willingness to share your knowledge!

cheers guys,
Jon

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Mark Alan Miller
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Post by Mark Alan Miller » Sat Aug 05, 2006 7:40 am

Some mics can actually come wired where a compression yeilds a negative voltage. Whether or not this is "wrong" is up to the manuafacturer, but most agree that a compression should veild a positive voltage.

And regardless of this (assuming, for example, that all you mics behave the same way) you should still check polarity in the way I described - looking at the kit mics in relation to each other and choosing polarity that sounds best to you.
he took a duck in the face at two and hundred fifty knots.

http://www.radio-valkyrie.com/ao/aoindex.htm - download the new record (free is an option!) or get it on CD.

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Jon Nolan
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Post by Jon Nolan » Sat Aug 05, 2006 8:40 am

Mark Alan Miller wrote:Some mics can actually come wired where a compression yeilds a negative voltage. Whether or not this is "wrong" is up to the manuafacturer, but most agree that a compression should veild a positive voltage.

And regardless of this (assuming, for example, that all you mics behave the same way) you should still check polarity in the way I described - looking at the kit mics in relation to each other and choosing polarity that sounds best to you.
thanks again. and btw - we must know some of the same ppl. drunk stuntmen, ray mason, jose a. etc - and you must know matt henert and the ware river club guys eh? my old band say zuzu (yes, a terrible name) and the WRC fellers played many a show together.

i'd love to see your place next time i'm out in western mass.

anyway, thanks again. i'll make sure to be vigilant about phase!

cheers,
Jon

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