What voltage capacitors for snack shack?

[EndlessOcean]

Howdy all,

I'm about to pull the trigger on a Snack Shack PCB and the parts list calls for some capacitors. I went to Small Bear to choose the ones from the parts list and they have a lot of options.

namely:

Capacitors, Panasonic Low Voltage Poly Film
Capacitors, Topmay Low Voltage Poly Film
Capacitors, Xicon High Voltage Poly Film
Capacitors, Mallory 150 Series Poly Film
Capacitors, Sprague 715 Series, Orange Drop
Capacitor, Sprague 716 Series, Orange Drop
Capacitors, Ceramic
Capacitors, Silver Mica
Capacitors, Electrolytic

I have no idea which ones to get for the pedal 

Everything else is in the cart good to go but these are proving problematic.

If you have any advice related to swapping something from the parts list for a better sound, I'm all ears

thanks, guys.

tez

[ckim715]

EIther the Topmay or Panasonics will do fine. As far as electrolytic capacitors, 25v is what I usually use.

[madbean]

Actually, in the case of the Snack Shack, I don't suggest the Topmay. You will want to use either the Panasonics or get some axial caps. C1 and C5 can be axial (like they are pictured in the layout) or radial--if you bend the leads a bit. C4 and C6 should be axial electrolytic.

Here's what you need:
Axial electrolytic: http://www.smallbearelec.com/Detail.bok?no=184

Looks like he's out of the 10uF but has the 47uF! You could probably get one at Radio Shack, though. If you run into trouble  finding it, let me know.

These should work for the space allotted. At worst you might have to bend the leads just a little.
C1: http://www.smallbearelec.com/Detail.bok?no=517
C5: http://www.smallbearelec.com/Detail.bok?no=518

[EndlessOcean]

wow, thanks for the reply and the links. It is true what they say about these forums

For C2 and C3 I should use the panasonics? Specifically, these fellas:

http://www.smallbearelec.com/Categories.bok?category=Capacitors,+Panasonic+Low+Voltage+Poly+Film

c2 = http://www.smallbearelec.com/Detail.bok?no=162 (the APEX one at 470pf)

c3 = can't find anything that is a Panasonic in a 47pf.

So lets say I go to radio shack to source the ones I can't get from Small Bear, am I looking for ceramic or something else?

thanks again

[madbean]

For caps valued at pF, you can do one of three types: ceramic, silver mica or film. Ceramic are the cheapest, mica are the most expensive. What's the difference? Very little! Ceramic will generally have a tiny bit more noise. Micas are usually considered a little more "hi-fi""....but that's subjective.

In the case of the Snack Shack, the two pF caps are used for smoothing out some of that distortion to kinda lop off a bit of its squarewave. My preference for that type of thing is usually ceramic...not because I've done some sorta scientific testing on its benefits, but rather that's what I have a lot of! In fact, just about the only time I use Mica is for something totally different: in the feedback loop of an op-amp, such as the Tube Screamer, et. al.

Film would be fine too here...but I don't think there is any added advantage. So, I would recommend just using ceramics.

[EndlessOcean]

so the one I linked above is fine for c2?

[madbean]

Since he has them grouped with the Panasonics, it's a fair guess that they are about the same size and can be subbed without issue.

[EndlessOcean]

I'll be taking a trip to RS and asking them for a 10uf capacitor, preferably a ceramic one.

[gtr2]

You want an axial 10uF electrolytic for C4.  I know you're looking for some info on what kind of caps for builds and there is a lot of good info if you search the forum (this and others)

[EndlessOcean]

believe me, I've searched this forum until my eyes calcify

I still couldn't find what voltage capacitors I need. 35v, 50v, 100v, 20v etc etc and from looking at the diagram i can't really tell either. Is it personal preference?

I ordered the parts linked above, the voltages of which weren't consistent so I'm wondering if it's an issue?

[madbean]

The supply is 9v. The standard voltage rating then would be 16v, 25, 35, 50v, and so on. Generally lower voltage rating means smaller size, but not always. Anyway, 16v will be fine.

I can send you a 10uF axial cap for your build along with the board order you made.

[EndlessOcean]

you = legend

[eniacmike]

I used sprague 715 series. total overkill but they look mojo riffic. and they fit, you just have to straight out the leads on the orange drops and they fit perfectly.

also I would say don't bother with the BC182L. I could hear no difference between that and a 2n3904 so I took it out. the pinout is different so you have to bend the leads around.

[EndlessOcean]

well that's interesting.

My parts arrived today and they look nothing like yours

I had ordered some 600v Mallory caps but Small Bear replaced them with some panasonic axial ones of the same value but smaller voltages... I guess those big orange things on your board are Mallory caps?

Also, what's the white resistor?

I have 2 of the blue caps, they say 47 uf on the side and they're both pretty small.

The trans all check out, the diode is good, the resistor values match up, but the caps I am not so sure about.

It's gonna be an interesting build.

[jkokura]

Can you snap a picture of the caps you got? Are you sure you ordered the right ones? Smallbear doesn't usually change your order without communicating with their customers. That's bad business...

Jacob