Capacitors for an Old Bryston 3B Amp

[wudevr]

Hi everyone.
I'm new here and am enjoying reading some of the threads.
I have an old Bryston 3B amp and I need to replace the capacitors.
The current one's are 50v 6800uF and are approx. 35mmx80mm in size.
There are 4 of them.
I'm having trouble finding suitable replacements.
I would like to use the current straps, so around 35mm diameter is ideal.
I'm hoping to leverage the collective brain here for some good suggestions 🙂
Thanks!

 

[Johnny2Bad]

Send an eMail to Bryston. They are very good at supporting their products, including long out-of-warranty products.

If for some reason you don't want to do that, I am unsure why you are having difficulty finding replacements. A 50V 6800 uF electrolytic cap in 35mm diameter is definitely not a difficult part to find at the usual places (Mouser, DigiKey, etc).

What is the lead spacing you require? Snap-In type or?

" ... I would like to use the current straps, so around 18mm diameter is ideal. ..."

Not understood. Can you elaborate? Provide a photo?

I assume you did search for Bryston 3B threads? If not, why not?

 

[kevinkr]

Not sure what you're asking. Are you suggesting that I search for existing Bryston 3B threads in the forums and hijack them with my question?

No please don't do that! 😀
It appeared you had started two threads in fact when you hadn't. I'm going to delete the note and response.

 

[kevinkr]

Are these computer grade caps not mounted on a PCB? I assume that is what the strap reference is about?

 

[wudevr]

Thanks Johnny2Bad and Kevinkr for your responses.
I originally had the wrong measurements for the Caps and that's why I was having trouble finding replacements (doh!) 🙂
What I meant to say originally was that I wanted replacement Caps that would fit the original Cap mounting "clamps", not straps, my mistake.
I ended up ordering 4 Caps from Digi-Key last night:
----------------------------------------------------------------------------------------------
Manufacturer=Vishay BC Components
Part Number=MAL205658103E3
Description=10000µF 63V Aluminum Capacitors Radial, Can - Snap-In 35 mOhm @ 100Hz 12000 Hrs @ 85°C
----------------------------------------------------------------------------------------------
I hope I made a good choice.
Thanks again,
Mark

 

[BenY]

This is what I had on my 3B.
It was 35mm X 105mm

 

[29285]

This is what I had on my 3B.
It was 35mm X 105mm

Roedersteins of that grade were excellent quality caps. For what reason do you intend to replace them?

 

[turk 182]

wow those are from a real early production model, what is the serial number of your amp or do you have any idea how old it is?

 

[BenY]

The Amp is from the mid 80s, It developed some hum, So I contacted Bryston and they sent me replacement capacitor Kit, that included two board adapters and snap-in type capacitors. All this for free, As customer service. I was amazed at their support and dedication to the product...
This was over ten years ago, when the amp was still covered by their 20 year warranty.

 

[wudevr]

I've replaced the 4 large capacitors and also the bridge rectifier on the left side as it appeared to have an issue. When I power on the amp, it is blowing one external fuse and one internal fuse, both on the left side. What should I check next to help isolate the issue?
Thanks.

 

[sgrossklass]

Make sure you installed all the new parts correctly. Reversed electrolytics, for example, are good for all kinds of fun, magic smoke and fireworks included.

 

[wudevr]

Thanks for the reply sgrossklass.
Thankfully there's been no smoke or fireworks 🙂
I pulled all 8 transistors and the amp powers up without blowing any fuses now. I will replace all 8 transistors and hopefully all will be well. I will report back with my result.