Bumble bee cap?

[nj pheonix]

Three part question. First is this a bumble bee? (the black one with the yellow stripes under the socket) .Second if its 50 years old, is safe to say its shot (well very likely)? Third if this were used as the input coupling cap on a power amp and it had a hum (assume PS is rebuilt and functioning properly here) could this cause a low level hum with no input signal?

 

[jbryant_77]

I'd say yes, yes and yes in that order..

 

[Dan ʕ•ᴥ•ʔ]

Buzzzzbzzzzzbzzzzzbuzzzzz...

 

[gadget73]

yes, yes, and maybe. Usually they fail with high internal leakage. If its the input cap, it *should* not matter if its leaky, provided that the preamp leaks no DC. I'd still replace it though. Most tube amps will hum some with no input signal. The high input impedance makes them sensitive to stuff like that.

 

[BrokenHill]

I just recapped a Zenith SE console pull tube amp, at first I replaced all of the electrolytic caps and the amp still had slight hum
just as you describe then I removed all of the bumble bee film caps and tested them and found all of them to have some leakage,
after they were replaced I had clean sound with no hum.

 

[nj pheonix]

Thanks