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Electronics Modifications

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With almost every guitar theres a whole host of secret tones you can get out of them without having to change your pickups.

Hot rodding

I'm going to demonstrate some of the more simple passive modifications that can be made to your guitar. Some of them will involve adding other components such as switches. All of these modifications are passive (i.e do not need a battery) and can be unobtrusive and reversible, they are my most popular mods.

Have a listen to my recordings and hear for yourself how you could unlock more tones from your guitar with my help!

Some of these modifications will require you to have pickups with 4 wires. Seymour Duncan and DiMarzio are good examples of these. I can convert a 2 wire humbucker to 4 wire for you if you wish too.

I also sell loads of Prewired custom circuits that you can DIY fit yourself! Click Here

Types of Upgrades

Pickup/coil selection:

Strat to Tele Mod  Series/Parallel Switching  Coil Tap Switching  Pickups in or out of phase 

Tone enhancement:

Passive Bass Rolloff control   Bass Boost/Treble cut switch  Push to make "Kill switch"  Treble/Bass Expander 

Varitone Circuit  Gretsch Style Varitone filter  Volume pot anti-treble bleed kit  Complete custom voiced electronics upgrade 

Coil tap

Coil tap is a very simple modification added to many guitars as stock. A humbucking pickup has 2 coils inside it usually they are wired one into the other (in series) resulting in one hot and one ground wire. A coil tap lets you 'tap' into the humbucker taking the signal from just one coil and shorts out the other coil. This effectively makes your humbucker a singlecoil. You will get more crisp sound, dont forget every different pickup performs differently too though.

Check it out: (Audio demo coming soon)

Series Parallel

You can experiment with the way in which your pickups are connected too. A Les Paul as standard comes with 2 humbuckers, when they're both on they are connected in parallel however the 2 coils inside a humbucker are connected as standard in series.

Of course a humbucker, as it is 2 coils, can be in series or parallel with itself:

Check it out:

Series/Parallel Switch - Fingerpicking Demo

Series/Parallel Switch - Overdrive demo

Series/Parallel Switch - Clean demo

Parallel gives a thinner sound compared to pickups connected in series. I find that a series/parallel switch provides some very useful tone that are very different to a coil tap.

Equipment used:
Yamaha AES-800 with DiMarzio Q-100 soapbar humbuckers
(very jazzy voiced) though a Carlsbro
TC60 re-issue Valve amp. sE2200a condenser mic and a
modded Ibanez Tubescreamer used for crunch demos.
No trickery!

Strat to Tele Mod

This is an awesome modification for Strats its really simple and doesn't compromise anything tonally. It enables you to get the bridge and neck pickup working together as well as all the pickups together.

You can have control using your existing pot for free, a small toggle switch for +£3 or have the mod activated by a push-pull pot for +£10 and still be able to use your original tone control! (Push-Push pots are now available too at £13)

New pickup selector functions:

Position  Standard  With blend control up 
Neck Neck and bridge
Neck and Middle All pickups
Middle only Middle only
Bridge and middle All pickups
Bridge Bridge and neck

Check it out:

Tele Mod for Stratocaster - Clean Demo

Tele Mod for Stratocaster - Distortion Demo

Listen closely as I switch between the different sounds. View comments to see which position the pickup selector switch is in.

Equipment used:
Fender mex Strat with stock pickups though a Carlsbro
TC60 re-issue Valve amp. sE2200a condenser mic and a
modded Ibanez Tubescreamer used for crunch demos.
No trickery!

Pickup Phase

As standard, all pickups are wired in phase. This means that when a coil generates a + signal the other one creates another + signal. If you make the pickups fight eachother by reversing the phase it will cancel out some of the frequencies leaving a thinner sound. Super funky!

You can also combine series/parallel with in/out of phase

Check it out:

In/out of Phase wiring modification - Funk demo

In/out of phase wiring modification - Surf Demo

In/out of phase wiring modification - Clean chords demo

Having trouble with the audio demos? Click here

*Note - a pickup's coil cannot be "out of phase" on its own, it needs to be out of phase with another coil. Humbuckers can do this within themselves as they are in effect 2 single coils stuck together!

Equipment used:
Teisco/Jedson Soldibody guitar with stock pickups though a Carlsbro
TC60 re-issue Valve amp. sE2200a condenser mic and a
modded Ibanez Tubescreamer used for crunch demos.
No trickery!

Treble Bass Expander pot

Fender TBX Circuit - Treble/Bass Expander

Fender have patented a small passive circuit gives you even more options. SImilar to the Strat-to-Tele mod, you sacrifice a tone control. The replacement pot has a notch at '5'. When under the halfway point the control acts as a normal tone control (attenuating high frequencies) and after 5 the control effectivley cuts your middle frequencies boosting the high trebles and bass frequencies. The result are slightly different for each guitar. Great for rhythm playing!

Varitone Swtich

Varitone Circuit

Originally designed by Gibson, the concept of varitone is similar to your average tone control except that it uses a range of different capacitors to attenuate (filter out) treble frequencies at a set level. You can use it to give your guitar alternate flavours. think of it as a Nothch Filter. Gretcsh also have their own version of the Varitone circuit using only 2 settings.

push pull pot

Push Pull switch pot

These are a great way to have some of these mods without having to drill extra holes for switches. The push pull pots are both a potentiometer and a DPDT switch in one, I also stock Push-Push pots too.


For some guitars some of these mods are not possible. For instance, I cannot wire in a series parallel switch for an Esquire Tele because there's only 1 coil. There's always something that can be hot rodded though!

Time to Mod?

Give me a call to see what you can get out of your guitar. Don't miss out on tonal options.

I take great pride in my soldering, I always make clean joints, use shielded wire when necessary and use shrink tubing to protect sensitive wires too, it can get fiddly though!

Contact Me today!

An electronics beast!

Couldn't help but pass up the opportunity to share with you the guitar with the most switches on. Ever.

Mark Denny came to me with a pile of guitar, neck body and an enormous box full of parts. He was after a John Squire Guitar which has never been sold as stock. John Squire had his half Jag half Strat made especially for him by Stuart Palmer. Now as stock the Fender Jaguar has a confusing amount of switches on already...

...Mark wated more switches.

I had to supply him with this manual detailing what each switch did.