reverse polarity

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Level 1

15 points

reverse polarity

Hey,

I'm reading about micing drums (and I use Garageband for the recording/mixing) and there is a not saying that the kick drum sounds better when the polarity is reversed and that it is apparently "easy" to do on a computer.

I have no idea how or if this can be in garageband. any ideas?

Posted on Oct 7, 2007 12:55 PM

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Answer 1

HangTime

Level 9

53,853 points

Oct 7, 2007 1:04 PM in response to llirik K

i've actually never heard that before, do you have any references? i'd be curious to read more, as i don't immediately see how inverting the signal would help

you definitely can not do that in GB, but you could look for an "invert" command in an audio editor:

http://www.bulletsandbones.com/GB/GBFAQ.html#audioeditors

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Answer 2

llirik K Author

Level 1

15 points

Oct 7, 2007 1:15 PM in response to HangTime

here is the link where i read this:

http://www.drumdojo.com/tech/mikingstudio.htm

"Second, many times the bass drum sounds better in the mix if you reverse its polarity. This is easy to do in computers and on higher end boards, but if you don't have one, you can make or buy an adapter cable that goes between the bass drum mic cable and your board. This only works for balanced XLR cables, though. To make one yourself, get a soldering iron (read and follow all the safety guidelines that come with the soldering iron) and reverse pins 2 and 3 on one end of a short XLR cable. "

this may be the same thing as phase relationships?

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Answer 3

HangTime

Level 9

53,853 points

Oct 7, 2007 1:19 PM in response to llirik K

yes, it would give a signal 180° out of phase from the original sound, i just don't understand how this would improve things. definitely calls for some reading on this (thanks for the link). i'm almost sure that audacity offers an invert option.

hey, if you do it, post back with what you find...i'm real curious if you find there's any improvement!

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Answer 4

llirik K Author

Level 1

15 points

Oct 7, 2007 1:25 PM in response to HangTime

reading around im getting the consensus that getting a cable that has this whole "phase" thing or whatever reversed is the best bet.

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Answer 5

HangTime

Level 9

53,853 points

Oct 7, 2007 1:28 PM in response to llirik K

that would be the easiest solution yeah, i'm sure there are simple adaptors that flip the pins, probably $10-$15 (as a guess)

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Answer 6

HangTime

Level 9

53,853 points

Oct 7, 2007 1:36 PM in response to llirik K

Whoa! i may have mis-spoke on that price guess, i did a quickie look and found this Shure Phase Reverser for $50! shop around, i'm sure you can find something better priced than this (or if you have a soldering iron, working on an xlr connector is not difficult assuming it's not one with a molded fitting)

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Answer 7

llirik K Author

Level 1

15 points

Oct 7, 2007 1:37 PM in response to HangTime

i'm still unable to fully grasp the concept of the phase stuff and how exactly that'll effect the sound of my kick drum.

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Answer 8

HangTime

Level 9

53,853 points

Oct 7, 2007 1:43 PM in response to llirik K

i'm might be missing something obvious, but i don't get it either. just changing the position of a mic could change it's phase relationship to the original sound. i've seen tricks where you use two mics out of phase with each other to help avoid feedback issues (though never messed with that myself), but never a single mic on a single instrument. i honestly don't know.

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Answer 9

HangTime

Level 9

53,853 points

Oct 7, 2007 1:49 PM in response to llirik K

i didn't read all of this, i just skimmed for keywords, but this seems to imply that the phase trick is for correcting a problem, not just as a standard thing to do. perhaps some info in here will help you:

http://homerecording.com/bbs/showthread.php?t=197952

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