Do Polypropylene caps break in?

[Firestorm]

Or just tell them the circuit is very unforgiving of sloppy playing styles. That way, they'll be too embarrassed to bring it back.

[rooster]

Ha! Firestorm that is very funny! Made my day.

[rooster]

BTW, here's my review of the new RelCap polypropylene and tin foil capacitor: This is hi-fi perhaps, at best. It is nothing you want in a guitar amp, IMO. Two big thumbs down.

By all means, spend the $$ if you want, but this cap as a coupling cap in an Express circuit (insert @ V2) sounded as 'smooth' (the seller's description) to the ear as swallowing a mouthful of ground up glass would seem to your throat. I wasted my $$ here, spare yourself. Oh, 16 hours of burn in.

[angelodp]

Burnt ..... in

[rooster]

Ha, Angel, that is true! Man, the rocks I have looked under to find some tone! And continuing with my brief description of how these things sounded, well, they seem to lack any midrange color - leaving a strange hole in the midrange, and a top end that amplifies every string hit on the guitar frets. In short, they perform like overtone robbers on the one hand, and a gift giver of a constant annoying clank/plink. BEAUTIFUL!!

Ha! Which is why I found Firestorm's comments so damn funny! Oh well, move on.

[VacuumVoodoo]

BTW, here's my review of the new RelCap polypropylene and tin foil capacitor: This is hi-fi perhaps, at best. It is nothing you want in a guitar amp, IMO. Two big thumbs down.

By all means, spend the $$ if you want, but this cap as a coupling cap in an Express circuit (insert @ V2) sounded as 'smooth' (the seller's description) to the ear as swallowing a mouthful of ground up glass would seem to your throat. I wasted my $$ here, spare yourself. Oh, 16 hours of burn in.

This is taken from RelCap distributors description, my emphasis in bold italics:
"This polystyrene cap exhibits the lowest DA and the highest stability in frequency and temperature characteristics. Its tin foil is compatible with the other materials used in the MultiCap, preventing oxidation and electrolysis and providing an extraordinarily stable long-term performance. "

Does this mean there is humid air inside the capacitors? Ah yes, they are hand made, hmm, if they were hand rolled on sweaty thighs by Thai maidens it would explain a lot...
Nothing about any need of burn-in in the specs either. They missed out on this important "audioholic grade" spec....
These caps are in oval shaped case not round. Why? Hand rolling never results in a homogeneous tight roll. They need to flatten it into oval shape to prevent the capacitor foil from vibrating with the signal and becoming microphonic.
Mind you, there are oval shaped capacitors by design for a totally different reason.
When choosing a component I go by numbers in the specs and major manufacturers technical app notes, not by adjectives in MBS brochure or website.
Have a nice Saturday everyone.

[rooster]

er.... I got stuck on 'sweaty Thai maiden's thighs'. What was it you were saying?

OK, these little caps are potted in black epoxy, in a tiny rectangular box made of plastic. Here, I assume, is the 'humidity protection' element of the design? I also assume they are axial in nature, but both leads are exited in the PC mount direction. Looking at other polystyrene caps of this value, I could easily see where any of those could be put in such a case, filled with epoxy and sold as 'trick' stuff. The difference seems to be the 'tin' foil vs. 'aluminum' foil construction --- or is one man's tin another man's aluminum? If such is the case, and prolly so, the only things these caps have going that is different is the epoxy filled plastic box. Eh, so maybe it's just a repackaging job? Well, then there's still those Thai maiden thighs to consider.....