phase reverse....whaaa?

[solaris0031]

people all the time mention things about phase reversing....what is it? i dont understand. From what i can figure out around here it has something to do with multiple mics being on the same source, but i have used 3 mics on my guitar amp before and i didnt notice anything wrong....(open back combo, bass mic in back, sm57 close mic, omni room mic)......am i retarded? also, does the "PFL" button on my yamaha mixer have anything to do with this?

 

[hasbeen]

I feel you pain...read this.

http://www.homerecording.com/bbs/showthread.php?t=128384

 

[Sonixx]

if you're micing an openback cab in the front and back, assuming the same distance from the source, you need to reverse the phase of the mic in back. the reason is that when the front mic sees a positive pressure (positive voltage output from mic), the back mic sees a negative pressure (negative voltage from the mic). When you sum these, you're getting significant wave cancellation. Same goes for drum micing such as snare or tom top and bottom head micing.

 

[Light]

if you're micing an openback cab in the front and back, assuming the same distance from the source, you need to reverse the phase of the mic in back. the reason is that when the front mic sees a positive pressure (positive voltage output from mic), the back mic sees a negative pressure (negative voltage from the mic). When you sum these, you're getting significant wave cancellation. Same goes for drum micing such as snare or tom top and bottom head micing.

Except that is not phase, it is polarity. Whatever the switch says, it does NOT effect phase. Phase is far more complex than that.

I was going to pontificate at length on this, but hasbeen has insured that I have already done so.


Light

"Coward can never be moral."
M.K. Gandhi

 

[Sonixx]

Except that is not phase, it is polarity. Whatever the switch says, it does NOT effect phase...

The point is well taken...