1uf Non-Electrolytic - What To Use?

[Brett]

I wonder - do the Pedal PCB boards limit polarized caps to non-signal positions?

Most of the boards on PedalPCB are true to the original pedals, AFAIK. @Robert has traced a ton of them. Of course not all of them will be film only caps in the signal path. A designer may have needed 10µF for a particular purpose and using an electrolytic was more appropriate.

Seems like 2.2uf and up is all-polarized (silkscreen-wise) on any pcb I've seen so far...

If a PedalPCB board shows a polarized cap, that's most likely what was in the original circuit, but you'd have to confirm with the Robert.

 

[Ginsly]

Most of the boards on PedalPCB are true to the original pedals, AFAIK. @Robert has traced a ton of them. Of course not all of them will be film only caps in the signal path. A designer may have needed 10µF for a particular purpose and using an electrolytic was more appropriate.

If a PedalPCB board shows a polarized cap, that's most likely what was in the original circuit, but you'd have to confirm with the Robert.

Makes perfect sense! Thanks Brett.

 

[MBFX]

I have a big bag of probably-Chinese 1uf MLCCs that are awesome. Teeny tiny, great tolerances so far.

Amazon

 

[koljaiczek]

I use this 1uf with good results

 

[jimilee]

I use this 1uf with good resultsView attachment 64105

Same here. I don’t care for the huge box caps.

 

[Big Monk]

I use 1u jb MLCC in the signal path of The Pompeii. I’m actually thinking of swapping ALL the film caps in the circuit with MLCC.

Literally ZERO difference to my ears and they have an overall great look with the blue electros and metal films.

 

[Robert]

Seems like 2.2uf and up is all-polarized (silkscreen-wise) on any pcb I've seen so far...

Higher value ceramics are much more common when SMD components are involved. I just traced one this past week with 47uF ceramics.

I'm seeing more and more designs where the entire signal path uses ceramic caps throughout. I'm talking well known, high regarded "boutique" builders. Not some cheap Joyo knockoff.

Tayda has through-hole MLCC up to 10uF:

Search results for: 'mlcc'

www.taydaelectronics.com

 

[Ginsly]

I have a big bag of probably-Chinese 1uf MLCCs that are awesome. Teeny tiny, great tolerances so far.

Amazon

Huh! Looks like the ones in that Amazon listing are all C0G/NP0 too, all the way up through 10uf. That’s the one thing that I’ve seen over and over again- those are fine, but X7R may be an issue and many higher uf values are only available in that dielectric.

@Robert - the ones you linked to at Tayda are largely X7R… sounds like this is not the issue many have made it out to be?

 

[Big Monk]

Huh! Looks like the ones in that Amazon listing are all C0G/NP0 too, all the way up through 10uf. That’s the one thing that I’ve seen over and over again- those are fine, but X7R may be an issue and many higher uf values are only available in that dielectric.

@Robert - the ones you linked to at Tayda are largely X7R… sounds like this is not the issue many have made it out to be?

Honestly, like most things, what may be best practice in the rest of the electronics world does not always apply to the devices I’m making.

I can’t guarantee it DOESN’T matter for other circuits, but for Vintage Style dirt boxes, it’s a non-issue.

 

[Ginsly]

Honestly, like most things, what may be best practice in the rest of the electronics world does not always apply to the devices I’m making.

I can’t guarantee it DOESN’T matter for other circuits, but for Vintage Style dirt boxes, it’s a non-issue.

This is kind of the pattern I’m seeing- it seems to be more of a risk with “clean” effects, less so with distortion and fuzz.

 

[jwin615]

microphonics are another thing to consider with ceramic, including mlccs. What may be fine in a practice scenario or on the bench might present issues 6 ft from a kick drum in front of a monitor...

 

[Big Monk]

microphonics are another thing to consider with ceramic, including mlccs. What may be fine in a practice scenario or on the bench might present issues 6 ft from a kick drum in front of a monitor...

As a guy who routinely cranks his amps right next to his pedalboard, with Fuzz Faces and MK II units pummeling them to within an inch of their life, I can say this isn’t an issue.

When I got back into building I was using the Aion FX “Where/What to Buy” document to procure components.

Now, I use what fits the aesthetic and takes up the least amount of space. Aesthetic uniformity and spacing trumps all else to me now so long as there are no Sonic downsides.

 

[MBFX]

Now, I use what fits the aesthetic and takes up the least amount of space. Aesthetic uniformity and spacing trumps all else to me now so long as there are no Sonic downsides.

Same here. I go for the most compact parts possible, so I'm regularly subbing film for MLCC and electrolytic for tantalum.

 

[jwin615]

As a guy who routinely cranks his amps right next to his pedalboard, with Fuzz Faces and MK II units pummeling them to within an inch of their life, I can say this isn’t an issue.

When I got back into building I was using the Aion FX “Where/What to Buy” document to procure components.

Now, I use what fits the aesthetic and takes up the least amount of space. Aesthetic uniformity and spacing trumps all else to me now so long as there are no Sonic downsides.

Therenare no rules for what you or anyone else here on the forum donor how they build. If aesthetics drive someone's design choices, more power to them. I would caution the verbage of "I can say this isn't an issue" though. It's a very real issue with ceramic caps. Always has been. Now, it's not an issue you've seen as detrimental to yours builds or designs, sure. White papers aside, there are pelnty of examples online including within the audio spectrum.
Not trying to debate or discredit here.
Hell, I had a meathead build once that would exhibit really odd pops and plosives on top of my bass amp that didn't occur when on the floor. I chased transistors for a bit because it was worst when wide open. Eventually swapping the cap and it cleared up.
But yeah. In a dirt pedal, what's 1% the or whatever could be a result of a handful of ceramics? Doesn't matter. Imperfect components in essentially imperfect circuits. I'd just hate for a new builder to show up, order a $5 kit of mlccs,.pop a whole board and wonder why their new "transparent OD" sounds like dogs**t because they read caps don't matter.
There's evidence that they do, while you can have evidence that in your use case that they really don't. Both those can be true.

 

[Big Monk]

Therenare no rules for what you or anyone else here on the forum donor how they build. If aesthetics drive someone's design choices, more power to them. I would caution the verbage of "I can say this isn't an issue" though. It's a very real issue with ceramic caps. Always has been. Now, it's not an issue you've seen as detrimental to yours builds or designs, sure. White papers aside, there are pelnty of examples online including within the audio spectrum.
Not trying to debate or discredit here.
Hell, I had a meathead build once that would exhibit really odd pops and plosives on top of my bass amp that didn't occur when on the floor. I chased transistors for a bit because it was worst when wide open. Eventually swapping the cap and it cleared up.
But yeah. In a dirt pedal, what's 1% the or whatever could be a result of a handful of ceramics? Doesn't matter. Imperfect components in essentially imperfect circuits. I'd just hate for a new builder to show up, order a $5 kit of mlccs,.pop a whole board and wonder why their new "transparent OD" sounds like dogs**t because they read caps don't matter.
There's evidence that they do, while you can have evidence that in your use case that they really don't. Both those can be true.

Bass amps vs. guitar amps is a whole different set of frequencies.

I can see the thump thumpers having issues with microphonic caps.

Not guitar players though.

Use your ears and decide there, not in the realm of technical papers. And I say that as an electrical engineer.

Side note: Put your pedals on the floor where they belong…

 

[Passinwind]

It looks like 1uf will largely (but not always) be non-polarized, whereas anything higher (even 2.2uf?) will likely be polarized. Is that kind of how it goes, or is it very much situational?

Definitely situational. I use film caps up to 6.8uF for coupling applications a lot. A Wima 1uF 50v cap is only 3.5mm wide, which is hardly what I'd call huge. I've been known to buy 100 at a time since they're all over my designs.

 

[Ginsly]

Very helpful thread, thanks all! When space allows, sounds like it's safest to stick with box caps for 1uf unless a polarized cap is specified. That being said, those 1uf MLCCs from Amazon that @MBFX posted look to be C0G/NP0 which is reassuring (a couple reviewers were skeptical and heated them up to see!). Given their dielectric, I would think they'd perform just like box caps - especially in a dirt box.

 

[MBFX]

Very helpful thread, thanks all! When space allows, sounds like it's safest to stick with box caps for 1uf unless a polarized cap is specified. That being said, those 1uf MLCCs from Amazon that @MBFX posted look to be C0G/NP0 which is reassuring (a couple reviewers were skeptical and heated them up to see!). Given their dielectric, I would think they'd perform just like box caps - especially in a dirt box.

Dirt boxes use such low current, and rely on fucking the signal up anyway, so choose components based on size and aesthetic.

 

[Ginsly]

Dirt boxes use such low current, and rely on fucking the signal up anyway, so choose components based on size and aesthetic.

Gotcha! In clean circuits I think I'd consider it more, but not for this pile of fuzz pcbs I have to tackle first...

 

[owlexifry]

Dirt boxes use such low current, and rely on fucking the signal up anyway, so choose components based on size and aesthetic.

you’ve just reminded me of a thread i read a while ago about the selection of bright caps in tube amps (particularly hot-rod/stock JCM800s), so we’re talking about caps that are freely passing higher frequencies to be obliterated with gain.
yes audio can be pretty subjective, but the general consensus was that:
- film caps sounded sterile
- ceramic caps were the most pleasing
- the ultra cheap shitty ceramic caps sounded ‘better’ than the expensive fancy ones.

so yeah, idk, i just found the whole concept of using ‘nasty’, cheap, ‘undesirable’ parts is something that could actually potentially be of benefit to circuits that encourage distortion.
hell you could even refer to that nastiness as ‘mojo’