EMG Geezer Butler tone cap change

[johnh89]

First post here . Recently bought a Geezer Butler passive P bass pickup from EMG and wanted to change the tone cap to 0.1uF . I searched here and across the internet and could not find much so did it myself and thought I would share it . For those who don't know , the plug and play pots from EMG are 250k for the GZR pickup and have a tiny surface mount 47nF tone cap soldered on the top of the PCB .I removed this with a fine point soldering Iron and replaced it with a 100v 100nF polyester film cap .
The location of the SMD capacitor is shown in this photo with the 2 solder pads
highlighted.

I then soldered the new cap from the CCW terminal of the pot to the ground solder pad on the back of the board , using a small piece of insulation on the lead to the ground pad to remove any chance of it shorting . The connection points are shown in the next picture .

Pictures of the completed pot are below

Whole thing only took 10 minutes . Waiting for new body to arrive so I can fit and see how the sound turns out . Not a difficult job to do is you are reasonably competent with a soldering iron and have a steady hand and decent eyesight (or glasses ) . I hope that is of some use to those of you who like to tinker . I am sure that this can be applied to any of the EMG passive tones with the appropriate value of cap .
By the way , the tone capacitors were about £1.30 for 10 . No boutique nonsense for me .

 

[simongpaez]

What was the issue with the original?
I love how it sounds straight out of the box

 

[johnh89]

What was the issue with the original?
I love how it sounds straight out of the box

No issue with original as not fitted to bass yet . I'm sure they sound fine out of the box as reviews on here convinced me to buy it . Always liked the darker tone of a 0.1 . It can easily be changed to anything later . It was a bit of an experiment while waiting for new P bass body to be delivered . Can't resist tinkering really !

 

[stratovani]

First post here . Recently bought a Geezer Butler passive P bass pickup from EMG and wanted to change the tone cap to 0.1uF . I searched here and across the internet and could not find much so did it myself and thought I would share it . For those who don't know , the plug and play pots from EMG are 250k for the GZR pickup and have a tiny surface mount 47nF tone cap soldered on the top of the PCB .I removed this with a fine point soldering Iron and replaced it with a 100v 100nF polyester film cap .
The location of the SMD capacitor is shown in this photo with the 2 solder pads
highlighted.

View attachment 4220539


I then soldered the new cap from the CCW terminal of the pot to the ground solder pad on the back of the board , using a small piece of insulation on the lead to the ground pad to remove any chance of it shorting . The connection points are shown in the next picture .

View attachment 4220538

Pictures of the completed pot are below
View attachment 4220540 View attachment 4220541 View attachment 4220542

Whole thing only took 10 minutes . Waiting for new body to arrive so I can fit and see how the sound turns out . Not a difficult job to do is you are reasonably competent with a soldering iron and have a steady hand and decent eyesight (or glasses ) . I hope that is of some use to those of you who like to tinker . I am sure that this can be applied to any of the EMG passive tones with the appropriate value of cap .
By the way , the tone capacitors were about £1.30 for 10 . No boutique nonsense for me .

I really like the idea of replacing the cap to 0.1uf. I also like the darker tone and I know I have the soldering skills to do this. Just one thing though. Would you be able to repost those photos but make them more in focus? They look a little blurry to me. Thanks.

 

[johnh89]

I'll have a go later . I was a bit blurry when I took them . What do you need to see specifically ?

 

[sunbeast]

If you have decent soldering tools (fine tip on an iron with decent heat, desoldering braid to clean up the pads, a set of tweezers to hold the cap, some fine solder) and a steady hand, replacing the original SMD capacitor with a 100nf SMD cap is also not particularly difficult and even cheaper!

 

[johnh89]

Rather you than me . Don't think that my eyesight would quite run to soldering SMD stuff but a very neat solution if done properly . I am too used to working with through hole components and space is not really a consideration as the they are 16mm pots . Hats off to you Sir !

 

[sunbeast]

Rather you than me . Don't think that my eyesight would quite run to soldering SMD stuff but a very neat solution if done properly . I am too used to working with through hole components and space is not really a consideration as the they are 16mm pots . Hats off to you Sir !

Another option to simplify would be to simply leave the original SMD capacitor and add another full-sized 47nf on the way you did. This would give you two 47nf capacitors in parallel, which would be nearly equivalent to a single 100nf capacitor (caps in parallel are summed, so 47+47=94nf). Just another simple option to consider!

 

[johnh89]

Or run two wires out and connect to varitone control ? Options are endless I suppose . The only advantage of the original idea is you can measure the exact capacitance of the replacement . Out of the 10 caps that I bought , all were within 2% tolerance . The one fitted measured at 100.1nF . I don't know what the tolerance is of the SMDs that EMG use . Not that important I suppose but a lot of peoples experience of tone capacitors seems to be based on an unknown value rather than a known quantity . Like I say , its not that important but will be nice to fit it when new bass body arrives and see what it sounds like .

 

[johnh89]

As requested stratovani , better pictures . If you need anything specific ask and I'll see what I can do

 

[PWRL]

I replaced the QP pickup that came in my American Special P with a Fender Original, which sounded better, but it still had the Greasebucket in it, so I took that out and put in a .1uF cap, which sounded way better to me, so I do understand.

 

[johnh89]

Now fitted to new parts built P bass . And yes it has flats and also a little bit of tort for all you lovers out there . First impressions are very favourable . From a quite bright sound with tone wide open , to a dub like thunderous bass with tone rolled off . Strings are roto jazz bass 77's so I am expecting the tone to mellow as they bed in . Only tried at rehersal last week so I will give it a go tonight and see how it sounds . For those of you who care about such things , the white ash bodied bass tips the scales at 12lb 2oz . Fine by me

 

[johnh89]

Sounds killer through TC BQ250 and 112 cab .
Just the sound I heard in my head .
Happy man

 

[mikecd1]

Big thank you to John for posting this! Your work made my job a lot easier and your description of the procedure was what convinced me to try. Although I have done extensive soldering over several decades this was my first real time soldering on a printed circuit board. The only thing I can add is just how small the capacitor is that is soldered to the board. Its so small that it just kind of came off on the very tip of my soldering pencil and almost didn't see it come off as it was so small. Once I saw that was home free and love-love the tone upgrade. It adds the perfect roll-off for me that really reminds me of the tonal possibilities I had on my first Pbass in the 60's.

 

[johnh89]

Big thank you to John for posting this! Your work made my job a lot easier and your description of the procedure was what convinced me to try. Although I have done extensive soldering over several decades this was my first real time soldering on a printed circuit board. The only thing I can add is just how small the capacitor is that is soldered to the board. Its so small that it just kind of came off on the very tip of my soldering pencil and almost didn't see it come off as it was so small. Once I saw that was home free and love-love the tone upgrade. It adds the perfect roll-off for me that really reminds me of the tonal possibilities I had on my first Pbass in the 60's.
View attachment 4870096

Good work that man ! Glad the idea was of use and the pictures helpful . Working with SMD components is a tricky business .

 

[LetItGrowTone]

Info:
The original cap installed by EMG, in the spot labeled 473, is actually a .022uF.
I metered this with a DE-5000, and @mouthmw also confirmed it via email with EMG.

 

[mikecd1]

Info:
The original cap installed by EMG, in the spot labeled 473, is actually a .022uF.
I metered this with a DE-5000, and @mouthmw also confirmed it via email with EMG.

That makes sense as I always felt the roll off favored a higher pitched / thinner tone. Now it’s rather warm and hitting the sweet spot much easier.

 

[johnh89]

Info:
The original cap installed by EMG, in the spot labeled 473, is actually a .022uF.
I metered this with a DE-5000, and @mouthmw also confirmed it via email with EMG.

Interesting . I never played the pickups with the original cap installed . Just assumed that marked at 473 it was 47nF as that is standard markings . Well done for finding out the true value and confirming it .

 

[mouthmw]

I've been playing EMG GZR with the stock wiring for years and have now had several gigs with the classic harness installed (and 47nF cap) and it's a very noticeable difference. I've always played with the tone pot rolled off to at least 50% and it's just a different, more classic resonant frequency. It's a smoother, fuller tone, but the GZR still growls when you dig in. I find the tone pot range more usable now, and now I even use it at 0% at certain moments when I need that super smooth tone. Could never get that with the stock 22nF cap so I stopped using it at 0% all together back then. Definite recommendation for anyone who wants that classic vintage tone with the EMG GZR. Switch out the cap or solder the pup to a harness of your liking.

 

[Hot Rats]

This is my geezer tone pot. I don't see a cap anywhere. Am I missing something?