[Lost81]

Hi guys,

Elna Cerafines have been described as somewhat lacking in bass when used as power supply capacitors in amplifiers.
Now, what about when they are used as power filtering in a tube preamplifier?

I am thinking of replacing a single 30mm x 25mm Jamicon 47uF 450V with an Elna Cerafine 47uF 500V 25mm x 50mm.

The path of the B+ on my preamplifier from the transformer is thus:

From rectifiers 238VDC (no load)
Xicon 10uF 450V Electrolytic
Solen 1uF 450V Metalized Propylene Film
6 feet of Belden 19364
Jamicon 47uF 450V Electrolytic
 resistor
Diode
 resistor
Black Gate VK 150uF 350V
 resistor
Black Gate VK 22uF 350V
6DJ8 tube

The 6 feet of Belden 19364 wire serves as a secondary power / umbilical cord as I built my pre-amp with an outboard power supply.

Will the 47uF 500V Elna Cerafine take away some of the bass?
I don't see how a Cerafine can pale in anyway next to a humble Jamicon.

I must say that I am VERY HAPPY with my preamplifier at this point.
I honestly can't see how it can be any better, but I am curious to see how far I can push it component-wise.
Maybe replacing that $3 Xicon 10uF 47uF Electrolytic capcitor (16mm x 25mm) with a $6 AEON / Solen Film and Foil capacitor (33mm x 43mm)I have sitting in the parts bin

Thanks!


-Lost81

[jeffreybehr]

I'd replace ALL those 'lytics with Solen/Axon/SCR 'propylenes.  You can buy 30uF/400vdc Solens for $10 from Michael Percy.  The closer to the tube you get, the higher quality the bypass caps should be.

I might even be tempted to replace the last 2 'lytics with 4/425 TRT DynamiCaps.

[Lost81]

... The closer to the tube you get, the higher quality the bypass caps should be.

Thanks, Jeff. That's what I was told too


-Lost81