'Partial' coil tap/split experience..

ram_man

New member
Evening all..

Asking if anyone has experimented with a partial coil tap or split (similar to PRS DGT).

PRS use resitors to leave a percentage of the second coil still active but I read that capacitors can be used with better results, anyone tried it? Suggested values or a formula to help decide?

Thanks
 
Re: 'Partial' coil tap/split experience..

Going try a resistor and cap in series before gournd, hopefully the cap will filter out some of the treble, leaving a fuller tone, we'll see..
 
Re: 'Partial' coil tap/split experience..

Keep us posted. I'll be interested in your results!
 
Re: 'Partial' coil tap/split experience..

Why not use spin-a-split? You can dial in as much, or as little of the 2nd coil as you want. Sounds like it's much more versatile and simpler than what PRS is doing.
 
Re: 'Partial' coil tap/split experience..

Why not use spin-a-split? You can dial in as much, or as little of the 2nd coil as you want. Sounds like it's much more versatile and simpler than what PRS is doing.

Not sure how that would work on my setup, one volume, one tone, both push pulls, would I lose my tone pot that way?

Having read some more I'm not going to use a cap, I'm led to believe that will just make one coil sound like the tone control is turned all the way down, making my actual tone pot pretty useless in split mode. Just need time to get the soldering iron out! Can't help tinkering!

So far I'm planning to use a 1k2 on the neck and 2k2 on the bridge
 
Re: 'Partial' coil tap/split experience..

I tried the spin-a-split once. It was fun for a minute or two. I always ended up with the pot full up or full down. Now I use a switch. ;)

YMMV.
 
Re: 'Partial' coil tap/split experience..

I tried the spin-a-split once. It was fun for a minute or two. I always ended up with the pot full up or full down. Now I use a switch.

I always use spin-a-splits in the middle, with unbalanced coils. Really makes a neck HB comes alive, without losing the output of coil cut.
 
Re: 'Partial' coil tap/split experience..

I tried the spin-a-split once. It was fun for a minute or two. I always ended up with the pot full up or full down. Now I use a switch. ;)

YMMV.

Done with a 250K linear pot, and reversed respect of "standard" (that is, shorting to hot, instead of ground, in an attempt to avoid some of the overall loudness being derived to ground), my experience is that:
there are three main clearly distinguishable spots, that have their use.
There are two minor notch positions between those.
User. with a single hot bridge humbucker is really happy with the mod.
 
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Re: 'Partial' coil tap/split experience..

This is what I'm intending to go with, comments and advice welcomed, new to modding and loving it!

Guitar is a Michael Kelly


Split Using APH-1n outer rs.jpg
 

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Re: 'Partial' coil tap/split experience..

This is what I'm intending to go with, comments and advice welcomed, new to modding and loving it!

Guitar is a Michael Kelly

I've just installed those cap values in series to ground on my two gigging Hamer Studios, which have DM 36th Anni pickups.

I like the result with the 2k2 bridge and 1k2 neck resistors.

There is less volume difference between spilt and full HB now, and the split tone is fuller, not so weak. I'm going to live with them for a while and then probably attack my other guitars that have splits.

Split tones before the mod, for me were something to put up with for versatility's sake. My new tones are sort of "Yea!, I could use that in its own right". They aren't Fender single coil territory but more P90 side of things. I hope that makes sense.
 
Re: 'Partial' coil tap/split experience..

LOL, looking at the date of my first post in this thread, I see its taken me nearly 2 years to get around to trying this mod!
Hope you're all alive and well.
:wave::wave:
 
Re: 'Partial' coil tap/split experience..

I've just installed those cap values in series to ground on my two gigging Hamer Studios, which have DM 36th Anni pickups.

I like the result with the 2k2 bridge and 1k2 neck resistors.

There is less volume difference between spilt and full HB now, and the split tone is fuller, not so weak. I'm going to live with them for a while and then probably attack my other guitars that have splits.

Split tones before the mod, for me were something to put up with for versatility's sake. My new tones are sort of "Yea!, I could use that in its own right". They aren't Fender single coil territory but more P90 side of things. I hope that makes sense.

Good times. Had I seen your OP two years ago I would have suggested a 4.7kohm resistor; that's a common "not quite off" tone mod creating a higher minimum setting to prevent the low-mid hump. Audio-wise there'd only be a 3dB difference in the second coil's remaining high end output between that value and the one you went with. Couple that with a .01uF or .02uF tone cap, essentially creating a fixed tone dump circuit for your second coil, and you could theoretically get a good blend of humbucking lows, keeping most of the 60-cycle hum out, with sharper single-coil highs.

I'm considering an "inside/outside" coil split mod on my Epi LP; I might just incorporate this into the split. If I do I'll let you guys know how it turns out.
 
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Re: 'Partial' coil tap/split experience..

I dunno, is it wrong to bump this thread? It seems ot be one of the best regarding this topic...

I am wiring up a HH guitar presently. How has the partial coil tap worked for everyone?
I really REALLY wish I could hear it for myself before I commit to wiring it up!

On a side note, I found some 10k trim pots which I want to use in place of the resistors.
 
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Re: 'Partial' coil tap/split experience..

For posterity, I wanted to add my results with the 10k trim pots.
I actually don't like the tone so much when partially cut because the tone is more similar to the full humbucker and defeats the purpose. Sure, the output drop is a nuissance, but the contrast in tone is better when fully cut IMO.

I intend to measure small changes on the trim pots (ie. OFF up to ~9 o'clock) but if I don't hear a good compromise between added treble and output, I'm taking them out! Pickups are Pearly Gates set FWIW.
 
Re: 'Partial' coil tap/split experience..

I'll tag on too....

Dumb question, has anyone used a double gang pot to spin-a-split two pickups at once?
 
Re: 'Partial' coil tap/split experience..

I experimented some years ago with partial coil cuts of the of both inner and outer coils and thought the idea clever and the sound very usable. I preferred the sound of partially cut screw coils although to do this you obviously had to reverse the wiring. However I then got into the habit of splitting to the bridge slug and neck screw to get the virtual humbucker in parallel and stopped experimenting..

Question has anybody worked our a way of partially cutting the screw coil of a bridge humbucker so it fits with a partially cut slug coil of the neck Humbucker? I do not actually think its possible but the ingenuity of the members of this forum never ceases to surprise me.. OK I know you can do it by reversing the wiring but then things are out of bonk with the neck pup.
 
Re: 'Partial' coil tap/split experience..

And another mini-update: I measured around 880 ohms at 9 o'clock on the trim pots, so I went and soldered 860 ohm resistors for each pickup this morning before leaving for work. The bad news is I have to wait until I get home before trying it out. FWIW I wired mine to split to the screw coil for the neck position and to the slug coil for bridge.
 
Re: 'Partial' coil tap/split experience..

Yep, the 860 ohm resistors are doing a pretty good job, they're staying in. There is a tiny bit more output than full cut, but the highs and spankiness don't suffer. I even perceive slightly less hum.

This is a very good mod that more people should know about! When you think of it, using a higher value resistor can give a hybrid effect by allowing some of one coil's signal to ground out, thus mismatching them without changing wind/wire on one coil. If you check this thread out, a guy called Clorenzo plots a simulation on a frequency chart. Pretty darn cool if you ask me...

http://www.thegearpage.net/board/index.php?threads/anything-to-help-boost-split-pickup-volume.1302864/
 
Re: 'Partial' coil tap/split experience..

Natman...how exactly did you wire up the resistor to the bridge and push pull to get the screw coil partially cut? I am assuming that you did not simply reverse the hot and circuit ground as this would put neck and bridge out of phase.
 
Re: 'Partial' coil tap/split experience..

Natman...how exactly did you wire up the resistor to the bridge and push pull to get the screw coil partially cut? I am assuming that you did not simply reverse the hot and circuit ground as this would put neck and bridge out of phase.

Sure, it's very simple. Take your switch and add the resistor before going to ground.

Using the diagram below, you have to solder the green & bare to ground directly or else it won't work. The resistor goes from the bottom lug of the switch then to ground.

Switches2_Diag_3.gif


Of course the neck pickup is slightly different as the color codes change (blk becomes red, red & wht become grn & blk, green & bare become wht & bare) but the resisotr goes in the same place. Hope that's clear enough! I like what I am hearing and my N & B are in phase when split.
 
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