Parentheses Fuzz Capacitor Question.
- Thread starter Diatrive
- Start date
Nostradoomus
Well-known member
1uf film caps are rather big
That they are. In general though aren't Xu caps electro? And Xn film caps? Not being snotty, just want to make sure I get it right.
Also there are many other 1u rounds caps in the build. ie C20 is 1u but electro and all there are 1n for film.
Other than the markings on the PCB how would you know that 'this' 1u is a film cap but all the others are electro even though both are 1u?
Also there are many other 1u rounds caps in the build. ie C20 is 1u but electro and all there are 1n for film.
Other than the markings on the PCB how would you know that 'this' 1u is a film cap but all the others are electro even though both are 1u?
Nostradoomus
Well-known member
In general yes but I just go by what’s printed on the board.
Chuck D. Bones
Circuit Wizard
I think this points up an opportunity for improvement in the build docs: list the capacitor type. The Arachnid board does this in the case of the MLCC capacitors. Of course, we are always free to upgrade cap types as long as they will fit.
BTW, the dead giveaway for electrolytic capacitors is the polarity mark on the board.
BTW, the dead giveaway for electrolytic capacitors is the polarity mark on the board.
Hey, new here. One question: the build doc says MLCC...but this doesn't necessarily mean it has to be SMDs, right?
Nostradoomus
Well-known member
No there are through hole MLCCs (usually the little yellow ones) 
Thanks!!!No there are through hole MLCCs (usually the little yellow ones)
Chuck D. Bones
Circuit Wizard
Mine are blue, I hope they sound ok! I used to think that MLCC stood for Multi Layer Chip Capacitor, but it's actually Multi Layer Ceramic Capacitor.
A couple things to note about MLCCs:
- MLCCs are good in switching power supplies and high-speed digital circuits where performance at megahertz frequencies is important. They are not particularly well suited for audio circuits.
- MLCCs rated for <100V have reliability issues because the ceramic layers are so thin that they can develop shorts.
For my first Arachnid (Octagon) build, I followed the BOM. The ones I got from DigiKey (FK24X7S2A105K) are rated for 100V. Next time around, I'll use film for all of the ones in the audio path.
A couple things to note about MLCCs:
- MLCCs are good in switching power supplies and high-speed digital circuits where performance at megahertz frequencies is important. They are not particularly well suited for audio circuits.
- MLCCs rated for <100V have reliability issues because the ceramic layers are so thin that they can develop shorts.
For my first Arachnid (Octagon) build, I followed the BOM. The ones I got from DigiKey (FK24X7S2A105K) are rated for 100V. Next time around, I'll use film for all of the ones in the audio path.
Anotherpedalbuild
New member
The electro spaces usually have a square eyelet and a round eyelet, and a circular outline and a + - polarity marking. Some pcbs have a bipolar cap with a circular pcb outline. Generally, if you have a box outline, it will be a poly box or film cap (63v or 100v rating are generally good) unless it is less than 1nf (e.g. 100pf, 47pf etc.) If there's a schematic, electrolytic caps have a distinctive -I(- or -)I- marking as opposed to a non polarised cap which looks like -II- on the schematic. Please excuse me if these are things you already know.
SteveScott
Member
Nostradoomus
Well-known member
Yes. Often times nowadays they will use MLCC as a designation for SMD ceramic capacitors and Monolithic as through hole versions. Just don’t get monolithic and tantalum caps confused as tantalum are polarized!
Chuck D. Bones
Circuit Wizard
For sure ceramic caps have the potential to color the sound. Some pedal builders use them for that very purpose. Me, I want my capacitors to be as transparent as possible. It's really a matter of personal taste. The reliability issue for ceramic caps rated <100V is real. It may only affect a small percentage of the parts, but I've seen cross-sections of caps where the metal layers grew whiskers thru the ceramic dielectric.
Nostradoomus
Well-known member
I always make sure to buy C0G or NP0, class 1 all the way baby
K Pedals
Well-known member
Where do you get em from??
You got a link?¿
Robert
Reverse Engineer
I know there are plenty of discussions about why ceramics shouldn't be used in the audio path, with all sorts of fancy simulations and frequency-vs-dc bias graphs, etc etc... but the majority of the SMD boards I'm seeing in the past two years are almost 100% ceramics.
There are still some that use through-hole or SMD film, but those are becoming more and more rare.
Disclaimer: Call me hardheaded... I'm just not a fan of simulations. They have their application, but the number of threads that have been derailed because a simulation "proved" that a schematic couldn't possibly be accurate, only to find out that it was, just discourages me from sim discussions.
There are still some that use through-hole or SMD film, but those are becoming more and more rare.
Disclaimer: Call me hardheaded... I'm just not a fan of simulations. They have their application, but the number of threads that have been derailed because a simulation "proved" that a schematic couldn't possibly be accurate, only to find out that it was, just discourages me from sim discussions.
Nostradoomus
Well-known member
I get mine from DigiKey. I’ve gravitated towards quality not quantity in my builds lately, I’d rather have 10 quality caps than 100 spotty ones.
