View source for Instruments / Drums

[[Image:GretchDrums.gif]][[Image:Percussion.gif]][[Image:TrapKat.gif]][[Image:VDrums.gif]]

{{:Connections / Drums for Model I}}

== Out-of-Phase Overheads ==

Originally posted by Cliff-at-Bose: in Out of Phase Overheads <ref>[http://bose.infopop.cc/eve/forums/a/tpc/f/8566055944/m/4341033052/r/3781073052#3781073052  Cliff-at-Bose: in Out of Phase Overheads Original post in the Bose® Musicians Community Message Boards]</ref> 
[[Image:Male2Female_XYThumb.gif|Two Female to Male XLR|right]]
These are not "overheads" but 57's placed below the cymbals and above the top heads of a small kit. The mics are wired out of phase, basically 2 and 3 reversed on an XLR. There's lots written about this on our forum. But the basic idea is that the pair will cancel onstage bass but pick up local instruments on the kit, in an effort to reduce rebroadcasting onstage bass from the drum mics. This way we get a stronger signal than typical overheads and cleaner bass onstage. To "mix" these, just move the mics closer to the instrument you want to emphasize. Typical setup is on either side of the snare facing the snare. Snare is everywhere and there is no need to put a mic directly on it. It's actually pretty easy to set up and adjust, moving the mics around for a good kit mix. With 3 mics and only 2 inputs on the PS1, we get a really nice amplified sound for our shows. I listened to the output of the pair recently (multitrack recordings of a recent show) and the cancelling thing really works great. Give it a try. 

Hilmar-at-Bose talks about Wiring Two SM57s with a Y cord <ref>[http://bose.infopop.cc/eve/forums/a/tpc/f/3976055944/m/1441055631/r/1441055631 Hilmar-at-Bose talks about Wiring Two SM75s with a Y cord  Original post in the Bose® Musicians Community Message Boards]</ref> 

Here's the nerds view.

Wiring the the two mics out of phase creates essentially a "dipole". Everything that is in the middle (i.e. equal distance) between the two microphones will get equally but out-of-phase so it cancels when the two microphone signals are summed together. In essence it creates a "blind spot" for the microphones for whatever is right in the middle plane. For the drums, that's mainly the kick (as Larry pointed out) and also the drummer (when he/she is hemming and hawing, squeaking with the chair, yelling about or in general having a grand old time).

Another nice trick is to place the L1 that gets the mic signal somewhere in the middle plane of the microphones. This drastically reduces potential for feedback and unwanted regeneration.
Sound sources that are significantly closer to any one of the microphones are not much affected by the whole procedure.

[http://bose.infopop.cc/eve/forums/a/tpc/f/3976055944/m/1441055631?r=1441055631#1441055631 the original discussion] &larr; is highly recommended.

=== Sources for the Cables ===
Hilmar-at-Bose talks about buying  an out-of-phase adapter.<ref>[http://bose.infopop.cc/eve/forums/a/tpc/f/8566055944/m/2711064151?r=2721044351#2721044351 Hilmar-at-Bose talks about buying  an out-of-phase adapter]</ref> 


The Y-adapters are pretty rare, I don't think you can buy them on line. You can buy an ordinary 2-female/1-male XLR Y adapter like [http://www.audiopile.net/products/Mic_Instr_Cables/MP_Adaptor_Cbls/Two-fers/YFMM_and_YMFF/YFMM_and_YMFF_cutsheet.asp YMFF] type 

[[Image:YFMM_a2.jpg|200px|Y-Female to Male:Male]]

and put an [http://www.audiopile.net/products/Adaptors_Connectors/Adaptors/XLR_Barrel/adpt_xlrbarrel_CA-301/CA-301_cutsheet.asp XLR] phase inverter on one of the female ends.

[[Image:CA-301_male_200w.jpg|200px|XLR Phase Inverter]]

=== Do it yourself Phase Reversal ===

You can buy or make an ordinary 2-female/1-male XLR Y adapter like [http://www.audiopile.net/products/Mic_Instr_Cables/MP_Adaptor_Cbls/Two-fers/YFMM_and_YMFF/YFMM_and_YMFF_cutsheet.asp YMFF] type 

[[Image:YFMM_a2.jpg|200px|Y-Female to Male:Male]]

You will need to swap the wires on 2 and 3 on one of the ends that goes to a microphone.

[[Image:PinOutXLRFemale.gif]]



=== Out of Phase Condenser Microphones - Not Recommended === 
Hilmar-at-Bose talks about Wiring Two Condenser microphones with a Y cord<ref>[http://bose.infopop.cc/eve/forums/a/tpc/f/8566055944/m/2711064151?r=2721044351#2721044351 Hilmar-at-Bose talks about out of phase condenser microphones]</ref> 

I would NOT recommend the out-of-phase Y adapter (or any kind of Y-adapter for that matter) with condenser mics. These mics have build in preamplifiers and connecting the outputs directly will present the mics with the wrong input impedance.


Again, I would only recommend the adapter for dynamic microphones (like for example a Shure SM57). If you want to use KSM109s (which are nice microphones), you may have to use a little mini-mixer to combine the microphone signals. You can still use the XLR phase inverter on one channel to get the cancellation effect. The 109s should work for near field as well as for overhead. For near-field you might have to engage the -15 dB pad on the microphones.

<noinclude>

== Using the {{T1}} Kick Gate ==
{{:T1 ToneMatch® Audio Engine / KickGate}}



----
[[Category:Drums]]

[[Category:Instruments]]

[[Category:Phase]]


<references/>
</noinclude>