Threshold S/300 Recap Question

eliasb1979

Member
2018-06-26 3:58 pm
Hi,
I am in the process of recapping my Threshold S/300 and need a 47uf axial capacitor.

I typically use Elna Silmic II series, but they don't make an axial.

I was thinking about using the following bipolar Mundorf cap, since there are not a lot of axial options intended for audio applications (none on Mouser, for example):

(ECAP50-010) - 47uF 50V Mundorf ECap AC PLAIN electrolytic capacitor | Hifi Collective

Any issue with using a bipolar cap here?
Any other suggestions of a better choise?

Much appreciated.

Brad
 

eliasb1979

Member
2018-06-26 3:58 pm
Digikey has a TVA1315 audio grade axial 50V 500 uF 1.5" x .5"

Thanks, Nelson. I found a smaller and lower voltage 500uf TVA on Mouser that I am going to use.

Would you bother replacing the tantalum capacitors or any other components if the amp is sounding good? From what I read, the tantalums don't wear out. I'm also debating whether it is worth spending the money on new filter caps.

The amp is now about 35 years old and still sounding spectacular. Quite an achievement on your part.
 
replace all small electrolytics , including Tantalums

they were popular in that time , but later (with years) it was evident that they're ticking bombs

just put decent electrolytics instead or solid cap , if size permits

if there is no hum , don't bother with big caps , but have an eye to buy new ones when you spot good trade
 

RobertS61

Member
2007-07-02 9:49 pm
Thanks, Nelson. I found a smaller and lower voltage 500uf TVA on Mouser that I am going to use.

Would you bother replacing the tantalum capacitors or any other components if the amp is sounding good? From what I read, the tantalums don't wear out. I'm also debating whether it is worth spending the money on new filter caps.

The amp is now about 35 years old and still sounding spectacular. Quite an achievement on your part.

The schematic says that these cap should be 47uF (as I remember from the frontendboards of my S/1000 Series II and SA/1's) as you original specified and not 470uF. It's C6 in the schematic that I got from Nelson Pass:
https://www.diyaudio.com/forums/attachment.php?attachmentid=897424&stc=1&d=1606568650
 

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RobertS61

Member
2007-07-02 9:49 pm
Thanks for you reply regarding the tantalum cap.
That would be C5, the .15uf cap that's over the biaspots?

I already have a Stasis 3 which I find a very good amplifier especially at the low end. Is the S/300 its successor with approx. the same PSU and the same amount of outputtransistors?