Side by side capacitor shootout!

[BubbaKahuna]

My most recent score :: tons of Tropical Fish caps in a lot of different values.
Haven't counted them, but there are probably a few hundred all sorted and in labeled bags:





There seems to be a lot of Voodoo about these things and I'd like to see how much is truth and how much is true BS.
I'd like to build a couple identical effects to do a side by side comparison between Fishies and normal caps to see if there really is a difference in how they sound.
Plug my guitar into an A/B box with one on each side going into the same amp.  Run them off the same power supply too.
That should be about as true a test as any you can do.

Any suggestions for what kind of effect would be most influenced by cap selection that isn't a nightmare to build?
I'd prefer it not be a wah, too variable with the rocker pot, inductor Voodoo and all that and besides - that seems too cliche and done to death with no real consensus.
Something with just knobs and a switch to minimize variables.

Once done, I'd post clips with the effects side by side with various guitars and amps (I have plenty of each).

Cheers,
- JJ

[demonstar]

Maybe you could just make up a few very simple passive eq filters on a breadboard and give them a go. That would be keeping things to a minimum.

I suppose you could try just running the signal straight through a cap and nothing else. That would really be a direct test.

Have fun!

[Nitefly182]

Wahs are really the only thing people hype them up for but I guess you could build a fuzz with them and see what happens.

[soulsonic]

Maybe a really simple booster like a Rangemaster or a SHO. I figure with something simple like that, it would be fairly easy to hear any differences in coloration.
A Fuzz Face is another one that comes to mind.... I don't know if you have any fishies that are big enough for the FF input cap, but maybe you could just do the comparison for the output cap? You could just build a single FF and have the output cap in a socket or on a switch to swap between the fishy and the "normal" one.
OR, you could put a fish, a greenie, a ceramic, an orange drop, a 150, and all on a rotary switch! That's how I'd do it.

[mars_bringer_of_war]

One thing to keep in mind is the variance in all components. Even if you build 2 identical circuits save the caps, they might sound different for other reasons. In fact, if you build 2 identical fx with all the same exact components, they may sound different anyway.

[jooooosh]

One thing to keep in mind is the variance in all components. Even if you build 2 identical circuits save the caps, they might sound different for other reasons. In fact, if you build 2 identical fx with all the same exact components, they may sound different anyway.

That's what I was thinking... it'd be difficult to determine whether the difference you're hearing is from the different caps or component tolerances.  Unless you matched each component (resistors and caps, mainly) to within 1% of the same value the experiment would most likely yield misleading results.  The passive EQ filters sound like a good idea to keep this simple enough.

[s.r.v.]

i wouldnt do a fuzz, too much dependence on the transistor. i like the rotary switch idea, then you could do anything

[R.G.]

There seems to be a lot of Voodoo about these things and I'd like to see how much is truth and how much is true BS.
I'd like to build a couple identical effects to do a side by side comparison between Fishies and normal caps to see if there really is a difference in how they sound.
Plug my guitar into an A/B box with one on each side going into the same amp.  Run them off the same power supply too.
That should be about as true a test as any you can do.

Good for you. Nailing down the real facts instead of believing the hoopla is always good.

However, you have a problem. Your experimental method is deeply flawed. For the reasons you've heard in the other posts, you simply can't build two "identical" circuits to listen to the caps through and get a true reading. First, the circuits are not likely to be identical, and second not knowing what the capacitor is doing in the circuit means your results may be completely wrong.

It gets worse.

It's impossible for humans to do a test like you propose -  A-B selecting one then the other - and not imposing their biases on the test. For a fair test, someone else, not you, must do the switching between A and B so you don't know which is which.

It gets worse.

Not even A-B testing can be trusted. The person doing the switching between A and B for you can and probably will send out slight cues about the selection. This is how the famous horse that could do arithmetic worked. His owner, quite unintentionally, was giving the horse cues about what answers were correct. So you have to to blind testing, and probably blind A-B-X testing. This is set up so the person changing the "channel" doesn't know which it is. And one of the choices is "neither".

What people who do this kind of experimentation have found is that a lot of times it's hard to prove that a person even hears a difference at all, and so one of the results is whether you can even tell by listening that one cap is a tropical fish and the other not.

If you don't do the experiment well, you not only waste your time, you contribute to the fog of slush and misinformation around the issue.

[jakenold]

Nice catch - I use them mostly because they look really cool in a wah or fuzzface, and because they are easy to work with in a PTP-build. They are mostly of good quality as well, metal film and all. Use them for their mojo-effect, there's nothing wrong with that. They aren't magic, but they are of high quality and make people feel better about themselves. 

Kind regards, Jake

[ambulancevoice]

beautiful caps!!!
nice tubes in the background too, those black metal cased ones

[aloupos]

Here's an approach that might work: 

1.  Choose something with a relatively low parts count, but something where the caps really count.  Some of the ROG circuits would do nicely.  Only build 1.  Socket the caps in the tonestack. 

2.  Play two bars (or whatever) of notes, then chords, clean, recorded into your PC.

3.  Play the clips through the circuit with standard caps, recording this back into your PC.

4.  Socket the mojo caps and record it back into your PC. 

5.  Post each clip without identifying which is which to the forum. 

6.  Let the forum users decide!  Maybe create a list of qualities about the tone -- I'm no expert here, others can do better at describing sounds, so I'll leave it to them. 

I would be really interested to see the results.  You'd be like a mythbuster   maybe a mojobuster! 

I think it's important that you not label the clips (obviously you know which is which, so when everyone is done voting you can let people know which one wins!)  n-blind sample test

[Paul Perry (Frostwave)]

Don't build a test circuit with a 3080 in it!

And, match the transistors in the 2 circuits for gain.

Or, just build ONE circuit, with switched caps!

[brett]

Hi

What people who do this kind of experimentation have found is that a lot of times it's hard to prove that a person even hears a difference at all, and so one of the results is whether you can even tell by listening that one cap is a tropical fish and the other not.

All of the things that RG mentions can be used to help develop a "real" test.  Most "tests" are completely, utterly, and laughably useless. For example, reports of listening to expensive NOS tubes someone has bought isn't a test.  Any decision about the quality of such tubes is made BEFORE the purchase.  And the decision is always in the positive.

What I think you'll want, if you plan to continue, is a multi-method, multi-observer matrix (MMMOM).  Multi-method means that you'd build 5 different circuits, not just one.  As RG said, it you built only one, it might be a type that doesn't suit the caps, or it might have slightly different transistors or something.  But if you test across five (or ten, if you've got the time), that'll "average out" the other effects and you'll be able to tell whether it's the caps.  The multi-observer part is easy enough.  You'll need ten to thirty observer-testers because any one person might be half deaf (like me), or have grown up listening to electrolytic caps and will dislike tropical fish just because they're "different", etc.

However, you might also want to consider this: whatever the results, such a test develops a fact, which is most helpful, and most convincing, for people who *aren't* much interested in tropical fish caps.  Conversely, for those who are highly involved with caps, your fact is just one new element added (or rejected) to a rich, pre-existing view based on personal experience and beliefs.  Such "rich views" are almost unshakable.  In many fields of science, the evidence and facts gain acceptance only after a generation of "true believers", and parties with special interests, die off.

cheers

[Paul Marossy]

It's impossible for humans to do a test like you propose -  A-B selecting one then the other - and not imposing their biases on the test. For a fair test, someone else, not you, must do the switching between A and B so you don't know which is which.

Yep. And as I have maintained all along, I don't think 99% of people can truly hear the difference between a tropical fish cap and ye old film cap. Or a JRC4558 vs some other opamp. Or this brand 12AX7 vs. that brand 12AX7. And on and on, ad infinitum.

People should stick to the stuff that really does make a difference - like guitar pickups, different types of tonestacks and amps, etc. That's the stuff that makes a difference, not the imperceptable differences between this kind of cap vs. that one. The only exception I will make is for low voltage ceramic caps because the hysteresis is so bad on them.

That being said, I think the tropical fish caps are cool because of how they look. 

[afrogoose]

Yep. And as I have maintained all along, I don't think 99% of people can truly hear the difference between a tropical fish cap and ye old film cap. Or a JRC4558 vs some other opamp. Or this brand 12AX7 vs. that brand 12AX7. And on and on, ad infinitum.

I agree that the differences in opamps in say a tubescreamer is really pretty tiny, but I couldn't disagree more about different 12ax7 (especially in V1).  Not that it will sound like a different amp, but different tubes sound noticeably, um, different.

Another solution would be to use a looper, like the Boss RC2 or whatever brand/model.  You could record a passage, and then play it through a simple effect with the caps on a rotary switch or whatnot.  You could record all the different caps with the same passage and then A/B/C them.  See if you or your friends can tell a difference. 

[Paul Marossy]

I agree that the differences in opamps in say a tubescreamer is really pretty tiny, but I couldn't disagree more about different 12ax7 (especially in V1).  Not that it will sound like a different amp, but different tubes sound noticeably, um, different.

I think it depends on the amp. I could never really hear anything definitive. Now if you used a 12AT7 or a 12AU7 instead, yes, that's a perceptible difference in the sound because of the difference in gain. If all 12AX7s had the exact same mu, I suppose my statement might be closer to the truth. I know they vary some, though.

[caress]

no matter what, someone is always going to say they can hear a difference in opamps, caps, resistors, whatever...people all have different hearing - certain frequencies jump out at them, differences in volume make eq, depth of effect, etc. seem different, even the simple act of trying to hear differences can play tricks on your ears.  many people want to hear a difference because i think in general it makes them feel like their hearing or "taste" is superior or more advanced.  that being said, i think some people DO hear that stuff, it's just way to objective a subject in my opinion.
even if things are scientifically proven, people often try to find a way to contradict the results...

it would be interesting to do a blind poll on this forum, though.  if i were to do this i would:
build a rangemaster with caps on a rotary switch.
record a loop into a looper or computer so it is played with the same nuance every time.
send that through the rangemaster and record multiple clips, each one with a different cap type.
be sure to include some duplicate clips to trick people...
maybe ceramic, poly film, paper/oil, mica, electo np, electro +/-, tantalum?
8-10 clips total.  no labels.  leave the poll up for a week, then give the results.  hopefully more than 30 or 40 people will chime in.

[Paul Marossy]

many people want to hear a difference because i think in general it makes them feel like their hearing or "taste" is superior or more advanced.  that being said, i think some people DO hear that stuff, it's just way to objective a subject in my opinion.

Most of the time, I see a concrete difference between two different devices when looking at it on the scope. But I sure can't hear any big difference most of the time.

[bumblebee]

personally i wouldn't bother with a test, i'd just use them in whatever i was building,just like any other cap.

i dont buy mojo anything and use what parts i have.

i hear a difference between mkt,ceramic and greenie caps but thats about it and i use ceramics in certain fuzz as i like the texture it gives, no mojo involved as far as i'm concerned folks, what sounds good sounds good.

[Pedal love]

Jeff, I think its a great idea and I'm 100% behind it.