Black Gate Standard Polarized or PK Mini Polarized = Rubicon YK or YXE

[kurtbauer]

I'm looking to modify the input circuit for a current-production amplifier by changing out the Nichicon caps with Black Gates. However, when I got into the amp I found Rubicon YK and YXEs instead of Nichicons.

A very knowledgeable colleague of mine informed me that Rubicon was a Black Gate OEM (or vice versa?) and that I should look into bypassing rather than swapping out the Rubicons.

I'd like to look into bypassing but wanted to know the scoop on the relationship between these BG and Rubicon caps.

Any guidance would be appreciated.

K

[Damon Hill]

Black Gate electrolytic capacitors were produced by Rubycon for Jelmax and were a design peculiar to the latter. Apart from being produced on the same production equipment to Jelmax's specification, there's little connection between the products.

As Rubycon no longer produces the Black Gate capacitors and Jelmax apparently hasn't found another company willing to manufacture to their specification, these capacitors are going out of stock.

Black Gates appear to be an electrolytic capacitor, possibly semi-non-polarized, with a graphite-loaded electrolyte. Jelmax claimed lower noise, distortion and impedance; I don't know of any objective measurements to verify their claims in any way. Black Gates enjoyed an almost cult status among audiophiles, and much of their product line was notoriously expensive and reputed to have a long 'break-in' period.

I don't know of any comparable product on today's market.