Capacitor Shootout

[Guitarfreak]

I recently did some comparisons of some popular capacitors for the electric guitar and I thought I would share the results with you. I tested poly film caps which are the little green rectangles that have been the standard on fender strats for over twenty years. I also tested ceramic discs which are a bit more modern or so I'm told. I got a bunch of orange drops and even threw in a monolithic cap too, just for fun

Gear Used:
Guitar: Jackson RR3
Pickup: DiMarzio PAF PRO in the neck position
Amp: Tube Works 100w Head through Crate 4x10 cab
Mic: SM57 positioned at speaker edge pointed at center of speaker cone. Some may call this my signature position

Things to know before listening:
The differences aren't going to be as obvious as a microphone shootout. Don't expect it to sound like a different guitar playing each part, because it isn't going to. Each capacitor has it's own 'flare' if you will, accenting certain frequencies along the spectrum. You may notice that some make the sound relatively flat while others give the sound some depth. You may also notice that some sound w.a.r.m. while others are a bit harsh. That said, the differences are subtle but through a nice system and with a good pair of ears you should be able to detect the inherent differences.

Now without further ado, the files. They are in WAV format but I compressed them for upload, so I'm not sure if that harmed the file's quality at all but the compressed package takes up about half the space as the uncompressed files.

Capacitors Clean.zip

The cap names were too long for the file so here is what each letter is.

A - Polypropylene 400v Orange Drop .022
B - Polypropylene 400v Orange Drop .047
C - Polyester 400v Orange Drop .022
D - Polyester 400v Orange Drop .047
E - Monolithic .1
F - Ceramic Disc 50v .022
G - Ceramic Disc 50v .047
H - Poly Film 100v .022
I - Poly Film 100v .047
J - Polyester 100v Orange Drop .022
K - Polyester 100v Orange Drop .047

I may do the same test on distorted guitar in the near future if this gets good reviews

[P.P.T.]

I'm going to be a bit unpopular and say that capacitors don't matter.
The only thing tha maatters is the value of the capacitor as that will determine the cut-off frequency where the tone control rolls off the highs.
The highs get sent to ground and not to the amp.

The capacitor isn't in the signal path. It's like an exit on a freeway that has a filter that only allows the unwanted flow of traffic off. The rest of the traffic doesn't go that way.

Not being in the signal path, the quality of the capacitor will not affect the sound.

Any difference that you hear will be due to the fact that the tolerences of capacitors vary quite a lot and one that says 0.22 may really be 0.20 or 0.24, or even o.18 or 0.26. That variance will change the cutoff point.

Of course people will argue this endlessly.

The reason that they make higher quality caps is because not all circuits use caps in the way they are used in guitars as a frequency bleed filter.
And in some applications the exact value is more important so the more expensive ones will have tighter tolerences.

[garageband]

The capacitor isn't in the signal path. It's like an exit on a freeway that has a filter that only allows the unwanted flow of traffic off. The rest of the traffic doesn't go that way.

Of course it's in the signal path. If I outright short to ground the main signal, I've clearly altered the signal path. This is a variant of that technique.

Caps matter when you have the tone control on. You could argue "I never use the Tone control." Ceramics suck. Anything is better than those. On bass guitar, the difference can be huge.

[Guitarfreak]

I'll have to agree with Garageband. However, the cap makes much more difference with lower value pots because more signal is shorted to ground, or in this case, the capacitor. The effects are a bit dulled in this experiment however because I have 1 meg pots in my guitar so a lot less signal is actually going to the capacitor than in most guitars. If you can detect the subtle differences in tone and color then you can use your imagination as to what it would sound like with a less efficient pot setup.

[P.P.T.]

But the portion of the signal that goes to ground is no longer part of the signal that goes to the amp and is heard.

The cap is just a route to ground and that is not in the signal flow.
It doesn't matter what the quality of the cap is. Only the cutoff frequency matters.

[garageband]

The cap is just a route to ground and that is not in the signal flow

It really is. Draw it out and have a look. You wouldn't look at an amplifier schematic and decide that any components that go to ground are "not part of the signal path". Past the philosophical untruthfulness of the statement, it's also practically wrong in that engagement of the tone control changes the impedance of the guitar's circuit.

Caps really do sound different. They also make the instrument's circuitry interact with outboard equipment in subtly different ways.

I subbed out a paper in oil cap in my Jazz Bass that was so different from the cheapie ceramic one, I thought maybe I should change it back, because it no longer did that wooly, fuzzy bass thing. I got over it. It's actually tons clearer. Yes, of course I A/B'd playing the same part the same way through the same stuff with the same strings.

[Guitarfreak]

I find that capacitors have the greatest effect on picking dynamics and transients and things like that. PPT did you even listen to the files, or are you just arguing a moot point?

[ryanoliver]

You can tell there are differences but to such a small degree. I'm sure I could never tell in a blind test. I chose F as my preferred cap.

[P.P.T.]

I'd suggest that the difference in sound is due to thhe difference in capacitance rating.
Tolerences on capacitors can be +/- 20%.

Oh,

What I am saying applies to passive tone circuits.
I don' know about active circuits.

[Guitarfreak]

See, now that's progress, at least you are admitting that there is a difference. Albeit, a subtle one. I agree that a lot of the tonal characteristics come from the tolerance value and the fluctuations thereof. I also postulate that the dielectric material has a lot to do with the tone because if you compare the Orange Drops made from different materials some have more clarity than others. I also noticed that the .047 caps have pronounced low mids akin to analog tape while the .022 have a bit more clarity. The .1uf one sounds totally different than all the others and I'm still trying to decide if it's a good thing or a bad thing. I am still having trouble deciding which one I am going to install for good.

BTW guitar circuitry is passive, unless you have active pickups which I don't.