help on changing capacitors


Hello every one I need advice...I have a balanced audio technology vk-5i preamplifier that needs to change the output capacitors they are rated 1mfd at 400vdc this use to be made by Jensen but they are no longer in business, I contacted Bat but they asked more than 450 us for changing them, can you recommend a substitute and what brand should I buy?
Best Regards
Albert Saadia

asaadia
Hello every one I need advice...I have a balanced audio technology vk-5i preamplifier that needs to change the output capacitors they are rated 1mfd at 400vdc this use to be made by Jensen

I know they have a vague looking black line that "may" indicated they are electrolytic that would warrant changing them after >10 years, and the two would have to be back to back to make them "non polarized" which would mean you only have 1/2uF not 1uf.

But I’m not sure they are electrolytic. they may just be non polarized paralleled caps to give 2uf, and no need to change them. And there are no + or - markings on the PCB. also
https://ucarecdn.audiogon.com/d559b139-dd3a-4af1-943f-a6d63245f6c6/-/autorotate/yes/

http://oldsite.sophiaelectric.com/pages/parts/jensen/jensen_cap.htm

Cheers George
They’re not electrolytic capacitors. Because it’s a balanced circuit the output is through two output capacitors. So there are two 1uF 400V Jensen’s on the positive/negative output. (These caps appear to have a history of failure in these amps.)

The Miflex can be got here:  MIFLEX KFPM-01 Capacitor, 1.0uF 600Vdc, Copper Foil Polypropylene Film (partsconnexion.com)

Info on the caps:  http://www.miflex.com.pl/assets/dokumenty/KFPM-01-ENG.pdf (partsconnexion.com)
The key to changing out the capacitors is size.  Some caps are just to large to fit in tight spaces so be careful.  Increasing the numeric values for Power Supply capacitors will in general produces better bass so if you can fit them in, my recommendation is to do so.

I recently used the Milflex copper caps with very good results in sound reproduction - did not find them bright either.

Happy Listening.