Author Topic: 2000s Recap / Capacitor Parts Info  (Read 1619 times)

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Offline N2000s

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2000s Recap / Capacitor Parts Info
« on: April 17, 2011, 05:51:53 pm »
Recently bought a stock 1970 2000s with the tube rectifiers and will be soon replacing the power cord and recapping it. I have read many posts here and I know there is some differences of opinions on recapping but with this one I'd like to keep it very close to original specs and would love some help on narrowing down the best quality parts and suppliers.

A few photos of it now with original caps.





Parts considered so far.

30/20/20/20 uF @ 550/600 VDC (slightly higher values then stock)
Product Detail: Multi-section Electrolytic Capacitor

Sprague Atom 20F / 600V
http://store.tubedepot.com/cp-at-20-600v.html

(My 350B has two of these 20/600 caps and this 2000s has only one) Does this have to do with it having the tube rectifiers?

Electrolytic Capacitor, 50uF, 150VDC
VISHAY SPRAGUE|TVA1414-E3|CAPACITOR ALUM ELECT 50UF, 150V | Newark.com

I read a member used 47uf@250V bias caps to replace the 50/150. What would the different specs add here?

Anything I should also go ahead and do while it's at the tech?

« Last Edit: April 18, 2011, 07:35:47 am by EdBass »

Offline Oli

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Re: 2000s Recap / Capacitor Parts Info
« Reply #1 on: April 18, 2011, 01:56:52 am »
Hi,

I did a recap job on my 350B last year. I noticed the same but I think the other 20yF in the 2000S are from the big can cab. Maybe someone could check this. I had trouble with the two chokes too, so maybe it is agood idea to change them too as you opend up the amp. They are here:

http://store.triodestore.com/c354.html
 
As not beeing an expert I think you would not hear any difference between the 47yF and the 50yF, though I would always choose the one with the higher voltage.

Greetings

Oli


 
SUNN Sorado - 1969 / SUNN 2000S - 1970 / SUNN Sorado  - 1971 / SUNN 350B - 1973 / SUNN Coliseum 880 - 1973 / SUNN Concert Bass - 1972 / SUNN Concert Bass - 1979 / 2x SUNN 215B - 1970/75 / SUNN/SAD 2000S cab

Offline N2000s

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Re: 2000s Recap / Capacitor Parts Info
« Reply #2 on: April 22, 2011, 12:00:53 pm »
Wanted to find out if Dynakit has any plans for a larger can cap other than their 30-20-20-20 mfd @ 550/600 vdc and here's the reply I received back if any one was curious.
..............

"Hello,
             I know I read on one of the Guitar DIY forums...maybe the Sunn amp forum..that the early production Sunn amps used a Dynaco MK III amplifier in combination with a modified PAM-1 preamp. Somewhere in my achieves I have a schematic of this.
 
Currently we use either of these can capacitors of 80-40-30-20 mfd or 30-20-20-20 mfd @ 550/600 vdc with our new production Dynakit MK III amplifier. I have not had any failures or report of a problem of either of these capacitors in our MK III amplifier since we began offering these in back in 2006.
 
I posed this question to our supplier several months ago regarding a higher voltage rating for a new amplifier design we are considering which required a bit more voltage capability. Basically their response was "no can do". These caps are measurably different from the original Mallory design being each can is comprised of individual discrete electrolytic caps with a voltage rating of approximately 630 vdc. They are de-rated to 550/600 (surge) vdc when enclosed in the aluminum can. Heat dissipation I assume.
 
 
Regards,
 
Kevin @ Dynakit, Inc "

.............

Also, I'm still trying to find out if using two 20uf 600vdc like they used in later versions of the 2000s and 350B would be beneficial to do the same in my earlier 2000s without other mods? I believe they did the same with the Model T. Any ideas why the change and would this be ideal?
« Last Edit: April 22, 2011, 02:36:53 pm by N2000s »

Offline EdBass

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Re: 2000s Recap / Capacitor Parts Info
« Reply #3 on: April 22, 2011, 05:12:22 pm »
I don't think I understand; are you doing this work, or are you having a tech do it? Are you just sourcing parts for a qualified tech?
When you refer to replacing the power cord do you mean grounding the chassis?
If you are in fact having the work done by a qualified tech (a good idea IMO), I'd suggest discussing the new components with them before you drop the cash, rather than going by opinions on a website.
A lot has changed in the last 40 years...  :wink:

Offline N2000s

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Re: 2000s Recap / Capacitor Parts Info
« Reply #4 on: April 25, 2011, 05:50:18 pm »
As much as I love to learn about the inner workings of the amp and generally like to do as much as I can I agree it's better the 2000s makes a visit to a pro.

Offline EdBass

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Re: 2000s Recap / Capacitor Parts Info
« Reply #5 on: April 25, 2011, 06:32:25 pm »
Great idea. Tell the tech that you want to learn about your amp and ask to discuss what parts and mods in order to agree on "how much?", great way to learn IMO.
See what update mods they suggest, and ask what end result they might have before the work is done.
When you get close to doing it, there are updates that posters here have used successfully to make their amps more compatible with this millennium, but would likely be difficult to explain unless you had someone around with the savvy to integrate them into your old amp.
If you search around the site you'll find most of them.