mkt capacitor vs mylar capacitor

[Vrystaat]

Gooday all,
What would be the advantage to use a MKT capacitor over a Mylar capacitor on the signal input stage of an amplifier ? Which is the better ?

Regards
Jan

 

[sgrossklass]

MKT = metalized polyester
mylar = polyester film

So the basic dielectric is the same for both. Metalized film caps have a higher capacity density and are a touch less linear. Either should be fine as an input coupling cap. If you need extremely good linearity, the next big step up is polypropylene - at the cost of a physically bigger part, obviously.

Keep in mind that capacitor nonlinearity only matters when a significant part of the signal voltage actually drops over it. Hence the common practice of oversizing electrolytics by a factor of 10. If you do want a highpass without incurring a distortion penalty, you have to go film.

 

[maouna]

between a green polyester mylar film capacitor and a polyester film box type capacitor,which one do you suggest to use in a tone control?

 

[Welcome]

It doesn't matter what you use in an amplifier, in this non critical application it's all the same.

 

[ticknpop]

better to get polystyrene if possible and if you can find the right value or parallel to get the value.