Bottlehead Forum

General Category => Technical topics => Topic started by: dbishopbliss on November 23, 2010, 09:13:27 AM

Title: Power Supply Capacitors Types
Post by: dbishopbliss on November 23, 2010, 09:13:27 AM

I've started planning out my entry for the mid-atlantic bottleneck linestage competition. 

I've come across a power supply schematic that I'm interested in trying that calls for using a 10uF 600V capacitor and a 1uF 600V capacitor (among others).  Usually when I think power supplies I think electrolytics, but since the maximum voltage rating of most electrolytics is 400-450V and since these values are relatively small I was wondering what are the alternatives?

Please comment on using the following types of capacitors in a power supply:

10uF 600V PIO capacitors on ebay
10uF 630V Obbligato Film Oil caps
10uF 630V Solen Metalized Polypropelyne
10uF 600V Electrolytic from ebay

Thanks for your help

Title: Re: Power Supply Capacitors Types
Post by: Grainger49 on November 23, 2010, 10:02:33 AM

I would think the lowest ESR would be the Solen PP film, then the Obbligato, the PIO and finally the electrolytic.  That is just my guess.  The lower ESR the more dynamic, I hear.  I have PIO (motor run) for my line stage, FP 2.

Title: Re: Power Supply Capacitors Types
Post by: 2wo on November 23, 2010, 06:23:10 PM

Hi Dave,

I may be one of your competitors but I think a film cap is almost always better than an electrolytic. I am a fan of the Russian PIO's...John     

Title: Re: Power Supply Capacitors Types
Post by: chrisby on November 24, 2010, 09:40:11 AM

edit

Quote from: 2wo on November 23, 2010, 06:23:10 PM

Hi Dave,

I may be one of your competitors but I think a film cap is almost always better than an electrolytic.
...John     

Mundorf is another name to consider if you've got money burning a hole in your wallet.


I've been trying to use Solen films and choke filtered supplies whenever possible, but aside from the cost, they can often take up more cubic volume than will fit within the intended chassis dimensions.   

Title: Re: Power Supply Capacitors Types
Post by: dbishopbliss on November 24, 2010, 11:15:11 AM

Well, the competition limits us to $100 or less so I think Mundorf caps are out of the question.  :-)  I think I will go for the Solens.

Title: Re: Power Supply Capacitors Types
Post by: Jim R. on December 22, 2010, 09:41:22 AM

How about a 10uF motor run cap?  Very cheap and very nice in PSs.

-- Jim

Title: Re: Power Supply Capacitors Types
Post by: Grainger49 on December 22, 2010, 10:17:08 AM

I put 100uF 370V AC motor run caps as a PDMPS in my FP 2.  They cost way under $100.

Title: Re: Power Supply Capacitors Types
Post by: coca on December 22, 2010, 11:15:09 AM

keeping the impedance of the power supply low, Is a very desireable thing, thus, using a film cap having low ESR such as PIO, Solens,Motor runs is a huge advantage over electrolytics. The PIO and motor run oils are usually very stable as well.

Bernie.

Title: Re: Power Supply Capacitors Types
Post by: 2wo on December 22, 2010, 12:32:27 PM

If I build one, I already have way more linestages then I need.
 I would definitely use motor runs, best bang for the buck. Good bang for any buck.
 I think you will find that they compare favorably with the film caps you used in the 6V6  ...John