Cap Question

[StompIt]

Sorry for the noobie question, but still trying to learn.

As far as caps (other than electrolytic), how do you determine the best type of cap to use for a particular application?   I've seen some comments about using Wima / Topmay box caps in certain situations (Im assuming in a portion of the circuit where tone is affected).  I have ordered a bunch of ceramic caps and some polyfilm and box caps in a wide range of values, but Im just not sure where the type of cap actually matters.
Do the ceramics, which are generally cheaper, affect tone in a negative way?  Or is it just personal preference?

[petesz]

There are basically three kinds of capacitors: Electrolytic (the tube looking ones that are polarized eg they have a negative and a positive side), Film/box type (often green or red box shaped) , and Ceramic (the orange disc shaped ones).
For bigger values, say 1uf and above, you will generally use Electrolytic caps. You can recognize these on the madbean boards because they are the circle shapes.
For medium sized values, say 1nf - 1uf, generally you will use box caps.
Smaller values eg 1000pf and smaller will generally be the ceramic disc type.

To convert between uf-nf-pf please see: http://www.justradios.com/uFnFpF.html
It will give you a good idea of the range of values for capacitors.

As far as affecting tone, best thing to do is try it out! Some people say the secret to the big muff sound is using all ceramic caps.. who knows!

[StompIt]

Is this one an equivalent to the ceramic disk type?

http://www.newark.com/jsp/search/productdetail.jsp?SKU=46P6661

[petesz]

Looks like it yeah.

[StompIt]

Exclude electrolytics from the picture.

When an schematic call for a nonpolar .047uf cap, for instance, how do you make the call whether to use ceramic, poly, box, etc?  I guess thats my main question. 

Thanks for your help by the way...

[stecykmi]

film caps are typically preferred for audio applications. most people use those as much as possible when conditions allow. luckily for us, most of useful values in the audio range fall in the range covered by film caps.

[jkokura]

Are you asking about brands and type? Most of the time it doesn't matter much. I use what's readily available from my suppliers, is relatively the best economic option, and fits the PCB. I don't buy into the different brands or types sounding different theory.

Jacob

[madbean]

Exclude electrolytics from the picture.

When an schematic call for a nonpolar .047uf cap, for instance, how do you make the call whether to use ceramic, poly, box, etc?  I guess thats my main question. 

Thanks for your help by the way...

Usually non-polar indicates an electrolytic, but that doesn't mean you can't use a film or ceramic. Typically, you will use electrolytic or tantalum for 2.2uF and larger. You can use either film or electrolytic for 1uF...it depends on what the actual cap is doing. For anything that involves actual audio portions of a circuit, such as an output or filter cap, I will use film for everything between 1n and 1uF.

As Jacob said, it's mostly about economics. There is still a lot of debate over whether or not there is any difference between using a film versus ceramic, etc in terms of tone. It's easiest to just pick a brand/type that suits you and your application most easily and just stick with it. Cheaper, too if you buy in quantity!

[bigmufffuzzwizz]

Is this one an equivalent to the ceramic disk type?

http://www.newark.com/jsp/search/productdetail.jsp?SKU=46P6661

Yes these are called monolithic caps. They are similar to ceramic disk but are slightly more expensive most likely because they have a smaller tolerance %.

There really is no right answer except to follow what sounds best to you through experimentation. For example big muff caps are "supposed" to be all ceramic disk but the one's I've built, I did not follow that and I still got very pleasing results.
After a couple of builds you wont even be thinking about this anymore!

[gtr2]

After a couple of builds you wont even be thinking about this anymore!

This is very true....

[bigmufffuzzwizz]

It's still one of my goals to build the same pedal (hopefully a simple circuit ) with different caps to really see for myself! Think it would be fun and would really help me eradicate this subject at least in my mind!

[StompIt]

I ordered a bunch of ceramic monolythic from Newark.com and I just wanted to be sure that these are a good choice.   I also ordered a bunch of poly films in the same range as the ceramics from Futurlec, so I think I have the bases covered.

I mainly just dont want to get something thats not suitable.   But it sounds like they will work and I just to do some experimenting !