Capacitor Types

[joelorigo]

Hi, This is my first post. I'm petty new to pedal building so this is going to be a rookie question. I have build a few BYOC kits and just completed a Rullywow Queen Of Bone which was the first time I use the docs to purchase the parts separately. Those build documents list the types of capacitor used - ceramic, metal film, etc. I notice in the build docs on the pedals just list capacitor values. How is it that I know which capacitor to use for these builds?

 

[Nostradoomus]

This site is a bit different in that a bit of knowledge is assumed. As far as I can tell it’s a one man operation so I don’t think there is time to be updating the hundreds of build documents with capacitor types.

That’s not to say we aren’t helpful though!

For the most part, anything in the picofarad (pf) value will be a small ceramic capacitor. Anything in the nanofarad (nf) will be a film box type and anything in the microfarad (uf) will be an electrolytic. There are, of course, deviations from these rules (1uf ceramic caps come up a lot) so your best bet is to reference the spacing/shape on the board yourself.

If you are still a bit lost, post the project you are intent on building and we can for sure help you with it.

 

[DGWVI]

Generally speaking values in the pf (Picofarad) range will be ceramic, nf (nanofarad) will be film, and uf (microfarad) will be electrolytic.
Personally, I use multilayer ceramic capacitors for all ceramics and films. They're physically smaller than typical box type or chicklet type film caps

 

[joelorigo]

Thant makes sense. Thanks guys!

 

[Cucurbitam0schata]

I'm a visual person, so I've drawn this down real big on my scratch paper to get it in my head to help me remember p < n < u. Specifically:
1000 pF = 1nF
1000nF = 1uF

@Nostradoomus and @DGWVI are all over it. To repeat: 1 uF nonpolarized caps do come up every once in a while (...CDXL Reissue Envelop Filter, whoops!). Do take note of the shapes/spacing for those ~1uF caps.

I just wrote this up on reddit a couple weeks ago when someone else asked a similar question. So, I thought to paste it below if you want a few more explicit details (Not to out-do the pros who already weighed in. From one noob to another, cheers!)

//

In general, these the guidelines below are what I've used. Worked for me when building my PedalPCB projects. I really liked the "intro" pages over at tagboard effects. Check it out.

uF = Aluminum Electrolytic / Tantalum - These are the polarized ones. I've used electrolytics for the round, polarized capacitor, tantalums last longer though. Easy way to find them is they usually are listed in the uF range on these build docs. Make sure they are rated for over 16V, you can find most around 50V. When you start get

nF = Mylar film / Polyester Boxes - Nonpolarized. You can get a little creative with the box capacitors, but like others have said - be careful of them getting too big. I got a pack of 100 nF mylar film "greenies", just to play around with them and see if they could fit... and they're huge compared to the standard sized polyester boxes. In general, the smaller nF "greenies" will fit, just be wary of going past 50 nF or so. Make sure they are rated over 16V. I've had some creative soldering jobs with big greenies...

pF = Monolithic ceremic - Nonpolarized. These tiny yellow capacitors are good for the pF caps that you'll come across. Again, make sure they are rated over 16V. All of them over at Tayda are 50V.

Lastly - read up this guideline that @Jovi Bon Kenobi made, it's really helpful for a first time builder: "How to build a PedalPCB pedal"

 

[joelorigo]

View attachment 3175

I'm a visual person, so I've drawn this down real big on my scratch paper to get it in my head to help me remember p < n < u. Specifically:
1000 pF = 1nF
1000nF = 1uF

@Nostradoomus and @DGWVI are all over it. To repeat: 1 uF nonpolarized caps do come up every once in a while (...CDXL Reissue Envelop Filter, whoops!). Do take note of the shapes/spacing for those ~1uF caps.

I just wrote this up on reddit a couple weeks ago when someone else asked a similar question. So, I thought to paste it below if you want a few more explicit details (Not to out-do the pros who already weighed in. From one noob to another, cheers!)

//

In general, these the guidelines below are what I've used. Worked for me when building my PedalPCB projects. I really liked the "intro" pages over at tagboard effects. Check it out.

uF = Aluminum Electrolytic / Tantalum - These are the polarized ones. I've used electrolytics for the round, polarized capacitor, tantalums last longer though. Easy way to find them is they usually are listed in the uF range on these build docs. Make sure they are rated for over 16V, you can find most around 50V. When you start get

nF = Mylar film / Polyester Boxes - Nonpolarized. You can get a little creative with the box capacitors, but like others have said - be careful of them getting too big. I got a pack of 100 nF mylar film "greenies", just to play around with them and see if they could fit... and they're huge compared to the standard sized polyester boxes. In general, the smaller nF "greenies" will fit, just be wary of going past 50 nF or so. Make sure they are rated over 16V. I've had some creative soldering jobs with big greenies...

pF = Monolithic ceremic - Nonpolarized. These tiny yellow capacitors are good for the pF caps that you'll come across. Again, make sure they are rated over 16V. All of them over at Tayda are 50V.

Lastly - read up this guideline that @Jovi Bon Kenobi made, it's really helpful for a first time builder: "How to build a PedalPCB pedal"

Awesome! Thank you

 

[joelorigo]

Another question. I have several I'm interested in building. Those who build a lot, do you buy kits of the resistors, capacitors, etc. so you have them on hand, or buy per project? I saw this kit highlighted on a blog:

1280 Pieces 64 Values Resistor Kit, 1% Assorted Resistors 1 Ohm-10M Ohm 1/4W Metal Film Resistors Assortment with Storage Box for DIY Projects and Experiments: Amazon.com: Industrial & Scientific

1280 Pieces 64 Values Resistor Kit, 1% Assorted Resistors 1 Ohm-10M Ohm 1/4W Metal Film Resistors Assortment with Storage Box for DIY Projects and Experiments: Amazon.com: Industrial & Scientific

www.amazon.com

 

[Nostradoomus]

I’m down the rabbit hole far enough that I have enough parts for most projects I want to build.

Cheap, bulk components are tempting but I switched my mentality awhile back and prefer quality over quantity especially when it comes to polarized capacitors.

 

[DGWVI]

When I first started building, I'd just buy parts on a per-build basis. These days, I use Tayda for most components, and make sure to stock up on the most common values.

I find the kits to generally be a waste, as they'll come with a lot of values you won't be likely to use, or you'll end up with an overabundance of those that aren't used often.

 

[zgrav]

If you are relatively new to the hobby but think you are hooked, investing $14 in 68 values of 1% 1/4w metal film resistors is not a bad idea. Not much more than a penny each, and good inventory for builds. Or look for a similar kit with 1/8w resistors to get a smaller footprint. And getting a similar set of MLCC caps and small electrolytics are not a bad idea.

But you will still need to treat those as inventory that you restock when your supply gets low, and you add to that inventory by buying a few extra of the other parts you need for the projects you build. You will eventually hit a point where you will have on hand most of the resistors and caps you need for a build. Same goes for buying the other parts you find yourself using on pedal builds.

 

[Cucurbitam0schata]

If you're thinking of bulking up - I started out only purchasing 1/8 w resistors, instead of 1/4 w. About half the pedals I've been interested in so far use 1/8 w, and you can use them in place of 1/4 w resistors, no sweat, for these pedal builds.

 

[Chuck D. Bones]

My capacitor recommendations:
470pF and below: silver mica or MLCC. Silver mica is better, especially in the signal path. They are wider, so fitting is sometimes difficult.
470pF to 1uF: film except when MLCC or electrolytic are specifically called out in the build docs or PCB silkscreen.
1uF to 47uF: tantalum electrolytic. Tantalum caps are far superior electrically (and more expensive) compared to aluminum.
above 47uF: aluminum electrolytic.

As others have stated above, SIZE MATTERS. Make sure the parts you buy will fit the board. You can print the PCB artwork to scale and measure it. Most parts are spaced 0.1" (2.54mm) so if you use anything wider, you will have a very hard time getting it all in neatly.

Quality is crucial. You're going to expend a lot of time and effort building something that you can enjoy and be proud of. Don't screw it up with shitty parts. Spend a few extra pennies.

Passive parts are so inexpensive, I always order a generous number of spares so that I will... a) spread the shipping cost over more parts b) get a quantity discount and c) have (most of) the parts I need for future builds. When you develop a full-blown pedal-building Jones like the rest of us, you'll be buying resistors by 100's and caps 20 to 50 at a time. Note that I said "when" and not "if." ?

 

[Chuck D. Bones]

Another question. I have several I'm interested in building. Those who build a lot, do you buy kits of the resistors, capacitors, etc. so you have them on hand, or buy per project? I saw this kit highlighted on a blog:

1280 Pieces 64 Values Resistor Kit, 1% Assorted Resistors 1 Ohm-10M Ohm 1/4W Metal Film Resistors Assortment with Storage Box for DIY Projects and Experiments: Amazon.com: Industrial & Scientific

1280 Pieces 64 Values Resistor Kit, 1% Assorted Resistors 1 Ohm-10M Ohm 1/4W Metal Film Resistors Assortment with Storage Box for DIY Projects and Experiments: Amazon.com: Industrial & Scientific

www.amazon.com

Those Amazon 1/4W resistors will not fit every board. $13.99 for 1280 resistors is a little over a penny a part. You can get them for a penny a piece from Tayda in lots of 100. 1/8W MF resistors are two cents each per 100 at Mouser. That Amazon kit contains resistor values you'll never need. It's rare to use anything under 100 Ohms in a pedal.

 

[Cucurbitam0schata]

especially in the signal path

Ok, sorry for the potentially simple question: do you have a method for determining what's in the signal path (for silver mica and/or tantalum caps)? If you have a reading source or youtube vid or whatever you'd recommend, I'm all ears. No need to spend too much time going into it if it's a complicated write-up! Thanks for sharing your knowledge, @Chuck D. Bones !

 

[Nostradoomus]

I would look at some of madbean pedals build
documents, they have power and audio path traces highlighted and many tutorials available!

 

[Chuck D. Bones]

What Nostradoomus said. You have to study and understand the schematic.

Here's a short, over-simplified answer: if one end of the capacitor is connected to +9V and the other end is connected to ground, it's not directly in the signal path.

 

[Cucurbitam0schata]

Thanks, pals! I'll start doing some digging. Appreciate it.

 

[Dali]

I use this page quite often because sometime I ordered 47nF and receive 0.047uF so I double-check to write the value I'm "expecting" that was in the PedalPCB documentation.

Capacitor uF - nF - pF Conversion Chart

Capacitor uF - pF - pF Conversion Chart to help you convert between uF(MFD), pF and pF(MMFD) as you read schematics, repair radios and shop for capacitors.

www.justradios.com

I'm a builder by numbers... I don't know what I'm doing.

 

[metalguy55]

My capacitor recommendations:
470pF and below: silver mica or MLCC. Silver mica is better, especially in the signal path. They are wider, so fitting is sometimes difficult.
470pF to 1uF: film except when MLCC or electrolytic are specifically called out in the build docs or PCB silkscreen.
1uF to 47uF: tantalum electrolytic. Tantalum caps are far superior electrically (and more expensive) compared to aluminum.
above 47uF: aluminum electrolytic.

As others have stated above, SIZE MATTERS. Make sure the parts you buy will fit the board. You can print the PCB artwork to scale and measure it. Most parts are spaced 0.1" (2.54mm) so if you use anything wider, you will have a very hard time getting it all in neatly.

Quality is crucial. You're going to expend a lot of time and effort building something that you can enjoy and be proud of. Don't screw it up with shitty parts. Spend a few extra pennies.

Passive parts are so inexpensive, I always order a generous number of spares so that I will... a) spread the shipping cost over more parts b) get a quantity discount and c) have (most of) the parts I need for future builds. When you develop a full-blown pedal-building Jones like the rest of us, you'll be buying resistors by 100's and caps 20 to 50 at a time. Note that I said "when" and not "if." ?

I can't seem to find any information on tantalum electrolytic caps. When I search for them I only see yellow dipped caps. Are these the same?

 

[Chuck D. Bones]

Those are the ones you want.

They look like this: https://www.mouser.com/datasheet/2/40/tap-776819.pdf