Guitar Tone Capacitors is today’s subject. In the video included in this article, I am testing different capacitor values to find the best tone for an EMG Strat pickguard I am building.
I installed this pickguard on the labstrat I made. I modified this guitar heavily to be able to test every possible mod I want. It’s a pain to have to remove the strings or unscrew the neck every time. After a few time, some strings are breaking, or the neck holes screw are getting loose. It’s a waste of time and a loss of money.
This situation forced me to keep guitars that were not fully configured the way I wanted, simply because I did not want to disassemble them an umpteenth time, just to change a switch.
Now with this test guitar, I can swap a pickguard in seconds. I can imagine any weird mod, or stumble on an unusual schematic online and check it right away.
When I work on a new pickguard, I test it on this guitar until it fully satisfies me, without wasting time or ruining the original instrument.
Guitar Tone Capacitors Test
Each type of pickup sounds differently. Frequency is a strange thing. There’s nothing like trial and error to get the tone you want. It depends on many things, and the result can’t be a rule of thumb. You might not like the capacitor I picked. According to your gear or the style you play, you might be looking for something entirely different.
Nevertheless, I decided to test five different capacitor values. From 0.01uF up to 0.047 uF. I checked capacitors above 0.047 uF before recording the video, and they were are not usable on those type of pickups. A strat requires a bright and percussive sound. The big fat sound fits better on hollow body instrument or a guitar project intended for jazz sporting passive humbuckers. For this one, I want a funky and aggressive tone to oppose to my other guitars.
Capacitor value tested:
Potentiometers used are 25K. They are the proper value for active EMG pickups.
The capacitors used are all Mylar Film type. There’s no difference between, Mylar, ceramic and Paper in oil (PIO) capacitor except for the price.
Ceramics are even cheaper than Mylar, but they are more fragile on the long run. Oil caps are ridiculously pricey and the saying that it gives a warmer sound is just a myth. Please don’t buy a single capacitor for more than $20 a piece. You can have 1000s Mylar film capacitors for that price.
I’m testing each value with the tone pot set on 10, and I roll it back to zero to hear the difference and to check the spectrum and range of setting.
As a starting point, I started to test the clean sound without any capacitor, to listen to the unfiltered tone of the pickups. Then, I checked each cap starting from 0.01uF all the way up to 0.047 uF.
For the clean sound, I prefer the 0.033uF value. I noticed almost no difference in sound when the caps were set on ten compared to no capacitor, except with the .047uF capacitor. It means I don’t need to install a solo switch.
When I rolled back the tone pot to zero, the bigger values filter the most treble and volume. That’s why I don’t like the 0.047uF Capacitor. It filters out too much treble and volume, and I don’t like the type of sound I get in the low register.
The 0.033uF Seems ideal for the clean sound. It delivers the same tone on ten, and the bottom part of the capacitor is still usable on a guitar.
I tested them again using a crunch sound
Checking the 0.01uF was useless. That value barely changes the sound, even with the tone pot rolled back to zero. To save time, I only compared the last four values.
Everything changed. The 0.033uF capacitor sounds doll. It misses the bite that 0.022uf delivers.
Choosing a capacitor is a compromise between clean and crunch.
The 0.033uF offers more nuance in the low register, but the overall sound is muddy even in the high register compare the 0.022uF.
Since this guitar is intended to have a rock and to funk tone, I decided to opt for the 0.022uf.
As you probably noticed, there’s only one tone pot on this pickguard. I plan to test a passive midrange booster soon. If the mid boost blends well with these pickups, it might as well change again.
Up to now the better compromise is the 0.022uF capacitor for both sounds.
I’ll update you in an upcoming video. I’ll make the finished schematic available when the project is over.
I am Hervé Senni, a pro musician and performer for quite some time.
My main musical instrument is unquestionably the electric guitar. Nevertheless, I also perform bass guitar, mandolin, Ukulele, and invented string instruments. I am also a composer as well as an arranger. Over the years, repairing and trying to further improve electric guitars that a majority of times did not have to be upgraded converted me right into a self-taught luthier.