Which caps to use where?

[Bakmeel]

In the process of designing my Aleph Ono, I ran into pondering where it comes to choosing capacitors. With the Farnell Catalogue on my desk, I find various materials used, with all their own characteristics. Farnell Sells (amongst others):
- (Multilayer) Ceramic
- Polyester
- Polypropylene
- Polystyrene
- Silverd Mica
- Plastic Film

And then there are those special brands and types like Black Gates and Audyncap. I don't know all these brands, nor where to get them

On the other side, there are the applycations. Some caps are more important to the sound than others. I found these groups of applications the most interesting and important:

- Audio coupling / decoupling
- Filtering (the RIAA network)
- Noise suppression (on the power rails)
- Loading for the MM stage

My question is: which type of capacitor is best suited for which job, and where should I use those really special caps like Black Gates?

Thanx in advance,
Bouke

[transducer]

Bouke,

For audio coupling and filtering (riaa) use polystyrene or polypropylene.

Loading for the MM stage is usually small value, so polystyrene's are easier to find.

For power supply filtering, a combination of electrolytic, ceramic and tantalum is usually recommended. However, you must be careful not to set up a tank circuit. For safety, just use an electrolytic.

Do NOT use a ceramic or silvered mica for coupling or filtering, they have horrible distortion. Polycarbonates are only marginally usable, and rarely seen in good audio components today.

My 2 cents gleamed from years of reading about this stuff, and even a bit of actual testing An excellent article on this topic can be read at http://www.capacitors.com/pickcap/pickcap.htm

RonS