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Bottlehead Kits => Legacy Kit Products => Paramount => Topic started by: AudioDave on January 10, 2016, 11:07:06 AM

Title: Bypass Paramount Power Supply Electrolytics
Post by: AudioDave on January 10, 2016, 11:07:06 AM

In a previous post from a few years back it was suggested to bypass the last 2 power supply caps on the Paramount power supply circuit board (Gnd to +460v)  That person used a 3.3uF 630V film cap.   I have a couple of 0.47 / 600V teflons and was wondering if those would be good for bypassing?
Thanks!
Dave

Title: Re: Bypass Paramount Power Supply Electrolytics
Post by: johnsonad on January 10, 2016, 12:01:06 PM

This is a parafeed design. The last cap in the PS isn't as critical as it is in a series feed amp. The parafeed cap takes its place. Focus on it and be thankful that the Panasonics that come with the kit are good and cheap!

Title: Re: Bypass Paramount Power Supply Electrolytics
Post by: ToolGuyFred on January 25, 2016, 01:42:19 AM

I added 0.22uF Teflon Kommie Kaps to my son's Paramounts and I can definitely hear a reduction in the small ammount of sizzle and splash in the extreme treble. We are listening through Fostex drivers, including supertweeters. All coupling caps are Obligato Gold and the cathode bias cap is an Audio Note Kaisei (supposed to be the nearest modern offering to Black Gates).
Pictures here http://bottlehead.com/smf/index.php?topic=8733.0 (http://bottlehead.com/smf/index.php?topic=8733.0).

Title: Re: Bypass Paramount Power Supply Electrolytics
Post by: AudioDave on January 26, 2016, 02:24:41 AM

Thanks John!    Just so I am clear,  you bypassed the last 2 caps on the power supply board with the 0.22 uF Teflon Kommie cap?
Thanks!
Dave

Title: Re: Bypass Paramount Power Supply Electrolytics
Post by: ToolGuyFred on January 26, 2016, 10:26:31 AM

Quote from: AudioDave on January 26, 2016, 02:24:41 AM

Thanks John!    Just so I am clear,  you bypassed the last 2 caps on the power supply board with the 0.22 uF Teflon Kommie cap?
Thanks!
Dave

Yes. The twisted pair in the last picture goes to the 450V tracks where the HT wires poke through the top of the PSU board. To find the foil nearest the can, I put my DMM to the megohm scale and put one probe on the can. Dabbing one terminal gave no reading and the other a brief variable reading. The one which gave the reading goes to ground.

Title: Re: Bypass Paramount Power Supply Electrolytics
Post by: AudioDave on February 03, 2016, 01:12:40 PM

This might be a dumb question but its not my first and definitely not my last.  Instead of connecting the bypass cap at the power supply circuit board,  could I connect it at the end of the 5" TTP at 17U and 16U?  That would sure make it easier to install!
Thanks!
Dave

Title: Re: Bypass Paramount Power Supply Electrolytics
Post by: ToolGuyFred on February 15, 2016, 10:42:22 PM

Sorry, have been away from the forum for a while.

I don't see any reason why you shouldn't connect at the terminal strip. I chose the PSU board for a shorter wire run. I strongly advise twisting the wires as shown in my picture, though.