Differences between polyproprolene and polyester capacitors

[darren01]

Hello,

What are the differences between metalized polyproprolene and metalised polyester capacitors?

I would like to use one type for low frequency roll off but can't decide which is better.

In your opinion, why should I choose one over another?


D

[5th element]

It depends on the situation. Polyester caps are the worst pretty much of caps to use in an audio situation. However in a lowpass aplication for a bass driver ie sub frequencies maybe up to say 200hz, the benafit of a polyprop or polystyrene cap wouldnt be as noticed if at all. The benafits are really a clearer more transparent sound with more detail and all that. So in a bass aplication its not as important. However if this is a highpass on a midrange you will notice a difference.

[ThorstenL]

Konnichiwa,

Originally posted by 5th element
It depends on the situation. Polyester caps are the worst pretty much of caps to use in an audio situation.

With the exception of ANY electrolytic capacitor of course, including fancy price/name ones.... ;-)

Generally, the sonic difference between capacitors has to do with more than the dielectric film. I know some completly awfull sounding polypropylene capacitirs and some excellent sounding mylars....

Sayonara

[BrianL]

Bateman's series on capacitors in Electronics World over
the past couple years might be enlightening reading.

[Jonathan Bright]

The other difference of course is price. Around here polyester are generally cheaper than polyprops. But what' been written already is probaly all that needs to be said. I now avoid polyester like the plague. There was a story in an Aust. mag' some years ago of a large polyester cap retaining a "memory" of a previous charge for a long time.

[jackinnj]

Originally posted by Kuei Yang Wang
Konnichiwa,
With the exception of ANY electrolytic capacitor of course, including fancy price/name ones.... ;-)

ceramics don't improve results either. If you have to use an electrolytic bypass it with a 100N mylar.