Dummy Coil Help

[jaylow]

Hello,

 

I recently discovered the whole dummy coil idea, but I can't seem to find a wiring diagram of any sort to help me put one together. I've googled high and low, but no luck. Can anyone help me find a diagram. I have a pickup already that I'm planning to gut so I can use it as one. Thanks for your help guys!

[j*h]

you could try and look for a fender powerhouse strat wiring diagram,mine has a dummy coil.

[Wyatt]

Optimally, you would not use a dummy coil in a traditional PU location. Dummy coils should be placed away from the strings and other PU's. Otherwise, thanks to other PU's magentic fields, they may pick up so string vibration which would then be canceled, possibly affecting tone and output.

 

The best implemented one I can thing of is thhis one, the Suhr BPSSC backplate. The plate contains a dummy coil and places it well away from the strings in a location that needs no modifications on a Strat. It even includes a trimmer pot to dial it in, because when you add a dummy coil you are adding a coil it's resistance will affect out some (increase output in series, decrease output in parallel).

 

The Suhr, whose instructions are available at the below link adds the coil in series before between the PU's and ground. I assume the trim pots allow you to only add as much of the dummy coils resistance as necessary to cancel hum with minimal effect on output.

http://www.suhrguitars.com/downloads/pdf/BPSSC_Instruction_Manual.pdf

 

 

Obviously, it's not as well suited for a P-90 Les Paul Special or something.

 

The Gibson Blues Hawk also mounted it's dummy coil in the rear of the guitar as well...otherwise it's just P/Blues-90 with no poles and no magnets.

 

Both of these designs adds the dummy coil in series with the pickups.

 

The Blueshawk is a little complicated, the neck and middle PU's are RWRP to each other, and they hum-cancel when both PU's are selected, do the dummy coil is unused in the middle position. But in the individual positions, the dummy coil is added in series, with it being wired to act as RW to each pickup respectively.

 

 

The a aforementioned powerhouse Strat shoehorns the coil in at the controls.

 

But it connects in through the active preamp.

http://support.fender.com/diagrams/stratocaster/0139500_02A/SD0139500_02APg2.pdf

[KingHarvest]

jaylow I totally hear you!!! I'm going through the same thing. Sounds like Wyatt knew but just withheld the info anyway. Even told you how to wire it to two guitars that already had one in them, but not how to wire it to the one you have. Went so far as to try to sell you something that costs far more than a new set of noiseless pickups. Perhaps he's in on the conspiracy! Seriously... would somebody please once and for all post the schematic of how precisely to wire a dummy coil to a normal, Standard Stratocaster? Please, not the Powerhouse, which is wired completely and totally different, and whose schematic is freely, and readily available at Fender's website, and linked to in every other thread about this subject on the internet. I'm sorry if I sound like a butt, but it's crazy how many times I've seen this question commented on, and the person will just dismiss the idea or dodge the actual answer entirely!

[Wyatt]

 

jaylow I totally hear you!!! I'm going through the same thing. Sounds like Wyatt knew but just withheld the info anyway. Even told you how to wire it to two guitars that already had one in them, but not how to wire it to the one you have. Went so far as to try to sell you something that costs far more than a new set of noiseless pickups. Perhaps he's in on the conspiracy! Seriously... would somebody please once and for all post the schematic of how precisely to wire a dummy coil to a normal, Standard Stratocaster? Please, not the Powerhouse, which is wired completely and totally different, and whose schematic is freely, and readily available at Fender's website, and linked to in every other thread about this subject on the internet. I'm sorry if I sound like a butt, but it's crazy how many times I've seen this question commented on, and the person will just dismiss the idea or dodge the actual answer entirely!

 

 

The best way for Strats is to buy the Suhr backplate and dial it in. It's also the most trransparent use of a dummy coil (because there is ALWAYS a side-effect or compromise).

 

But for Strats WITHOUT a RWRP middle PU and just using any dummy coil....disconnect all three pickup grounds wire from the back of the volume pot. Connect all three ground wires to the hot wire of the dummy coil, attach the ground wire of the dummy coil to the back of the volume pot. Mount the dummy coil as FAR way from the other PU's and strings as possible.

 

But you now have an extra coil in series with the PU's at all times, so there will be achange in the character of the instrument. Dummy coils have been around for decades, and most noiseless single coils imply one underneath. But like many innovations, their side-effects usually make people abandon them. You could conceivably add a way to dail in/out some of the coil for the best balance, a la the Suhr trim pots.

[catscurlyear]

a friend put one in my jag,we got an old single coil pickup took off the casing he took off the magnet ,i think he also removed the pole pieces , routed a hole under the pick guard between the bridge and neck pickups ,stuck what was left of the dummy in the hole. can`t remember how he wired it up . but it works great ,i put a mini toggle on/off switch inbetween one of the wires so that i can turn it off if it aint needed. i would say there is a 5% decrease in treble when it is on if that.i would recomend it .i think it`s all about getting rid of the magnetic pull from the dummy pickup ,correct me if i`m wrong.

[Wyatt]

 

a friend put one in my jag,we got an old single coil pickup took off the casing he took off the magnet ,i think he also removed the pole pieces , routed a hole under the pick guard between the bridge and neck pickups ,stuck what was left of the dummy in the hole. can`t remember how he wired it up . but it works great ,i put a mini toggle on/off switch inbetween one of the wires so that i can turn it off if it aint needed. i would say there is a 5% decrease in treble when it is on if that.i would recomend it .i think it`s all about getting rid of the magnetic pull from the dummy pickup ,correct me if i`m wrong.

 

 

Totally wrong.

 

And I would be curious as to how you figure that removing magnetic pull would cancel electronic hum?

 

It's about having a coil that is reverse wound to the pickups' coils. The coil is the part of the PU that is susceptible to interference, so you introduce a version of that interference that is 180 degrees out of phase with that of the PU's. It's the same way a RWRP pickup cancels hum, but without the actual PU signal.

 

The closer it is to the other magnets and the strings the more you risk it acting like a weak PU and affecting tone.

[catscurlyear]

i meant getting rid of the magnets ,so it dosn`t pick up the strings ,my dummy coil is directly under the strings aprox 3/4 ins away ,and there are no probs , sorry if you misunderstood me.

[jaylow]

Thanks for the help guys. I've actually added it to my guitar and it seems to work just fine for killing most of the hum. It's not perfect, but it's killed off most of the hum. I don't mind the slight change in the tone either.