Cheap Russian 2.2uF 400V PIO Capacitor

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EC8010

EC8010

Ex-Moderator
Joined 2003
It's not so much the dielectric constant that's important (otherwise we'd all be using electrolytics), more, I think, the dielectric absorption which tends to be related to tan delta or leakage. In those terms, PTFE and polystyrene are top of the heap, with polypropylene second. Paper? Well, there are so many different types of "paper" that it's a very variable feast.

Edit: I've just cut and pasted the first reference you posted to read it in a decent sized fount. The author says the same thing, which is nice.

A link from your second reference gives the following information for dielectric constants:

COCAINE (68°F) 3.1
COFFEE REFUSE 2.4 - 2.6
COKE 1.1 - 2.2

What sort of person does these measurements, and why?
 
P

papparazzi

Member
Joined 2004
Hi

I have these caps and I have used them as coupling in my 300b PSU
Certain they have openess and easy on ear no stress but in .my oppinion they colour upped mids,dont sound very dynamic on highs
I found more resolution turning back to my previous Aydyn standard PP caps.
I try next in my speakers crossover Fostex F17 /and Supravox 215s


Papparazzi
 
rdf

rdf

Member
Joined 2004
EC8010 said:
It's not so much the dielectric constant that's important (otherwise we'd all be using electrolytics)....
Click to expand...

It's my understanding there's a rough correlation between low dielectric factor and cap performance. Polyethylene at 2.26 vs. Polypropylene at 2.2, definite possibilities, especially in the context of $2 caps. The second link surprisingly lists a GHz tangent loss superior to Teflon. I imagine much depends on the oil employed in this particular cap. After reading the sonic adjectives used though I'm keen of giving them a try!
And just 'wow' about the Vaseline.


What sort of person does these measurements, and why?
Click to expand...


A caffeine addled compulsive?
 
E

Eusebius

Member
Joined 2006
I found a purveyor of 250V 0.47uf and few left of 0.315uf 250V polystyrene caps, and bought every-last-one-of- them. Cleaned him out. I'll never see those again. >>

Sounds good, but there is CURRENT PRODUCTION polystyrene caps in UK from LCR caps

"We wish to dispel rumours that polystyrene capacitors are now obsolete. Although polystyrene material is no longer available we at LCR have aquired sufficient material to manufacture at the present scheduled rate for a minimum of 15-20 years."

They do up to 630v and up to 0.1uF. Ow bout dat!!

http://www.lcrcapacitors.co.uk/fsc.htm
 
K

KBK

Member
Joined 2003
KBK said:
hhmm..I found a purveyor of 250V 0.47uf and few left of 0.315uf 250V polystyrene caps, and bought every-last-one-of- them. Cleaned him out. I'll never see those again.

I'm waiting anxiously by my mailbox.....
Click to expand...

Yeah, but the combination of 250V..and 0.47uf???? Good freaking luck finding that.

Got them..and DAMN, they's good. whoa! Terrible quality control too. The very large majority (over 50%) are a lousy 0.00% uf value tolerance, and 00.00% matched. The other 40% or so, are 1.00% high, at 0.00% matching. Apalling. :D
 
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