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Old capacitors..Comments..

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M Gregg

M Gregg

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Joined 2010
Short simple question,

Looking at old style caps that sounded "Good"..or.."Bad"

What are Black Cat capacitors...new to me...(OK they are old)

What is the construction?

________________________________________

ITT made a plastic block polypropylene PMT/2R, RS had one that looked exactly the same with only the cap value and voltage. Is the RS one polypropylene or some other type? They looked like this:

2 PCS ITT-GB PMT/2R Molded Capacitor 2.2uF / 10% / 250V | eBay

Very common in ther 70's..Not used now..


Regards
M. Gregg
 
indianajo

indianajo

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Joined 2010
Black cats from 60's and 50's have a bad reputation as an economy paper cap. I believe I have seen lots of guitar amp people recommend their 100% replacement. I've owned other black paper caps from that era that lasted 50 years in tube service, made by GI. The GI ones were wax sealed, and the only one that deteriorated was one that had the wax case burned through by the installer in 1961.
 
kevinkr

kevinkr

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Black cats were made by CDE and were hardly economy caps IIRC, but were generally regarded as a relatively high quality and good sounding paper and foil cap. The case was hard black molded plastic, but like anything that old are subject to deterioration over time, usual failure mode is they get leaky. They're still regarded as good sounding by a certain segment of the audiophile community along with those notorious bumblebees.. (There are a segment of Japanese, Korean, and American audiophiles, not to mention guitar players seeking the vintage sound who prize them.)
 
kevinkr

kevinkr

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M Gregg said:
Thank's for the info,

I remember the old hunt's caps being a problem..


Regards
M. Gregg
Click to expand...


I've seen those in some vintage UK gear sold here in the US, and they have the same reliability issue as American made paper dielectric caps.

Jensen (DK) makes foil paper in oil types that seem to stand up OK over time, and might be worth checking out if you like a vintage sound.
 
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