2. amps-preamps
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Preamp power supply capacitor upgrade

I recently purchased a used Backert Labs Rhumba Extreme 1.3 preamplifier. Although it sounds excellent, I’m on a quest to get it to sound as close to the Backert Labs Rhythm as I can on the cheap. I’ve already sent it back for the 1.4 circuit upgrade and I upgraded the coupling caps to V-Cap ODAM’s. I’ve also upgraded the tubes to Amperex 7316’s from several recommendations here. For reference, my amplifier is Coincident Frankenstein 300B MkII and speakers are Reference 3A Reflectors.

The Rhythm power supply uses four 0.33uf V-Cap CuTF caps which gets rather costly at $218 each. However, the TFTF caps are discounted at $104 each.

My question is, since these would be used in the power supply, would the price differential justify going with the CuTF vs the TFTF?

Ag insider logo xs@2xyowser

Showing 2 responses by atmasphere

atmasphere's avatar
atmasphere
11,632 posts
 

@yowser Your goal here is, I assume, to improve performance.

To that end, by bypassing the power supply, what you want is uniform output impedance of the power supply at all frequencies. So the correct dielectric may not be the one that is also the most expensive!

I'd stay away from oil and paper parts as they have a way of developing electrical leakage and may also leak physically. We stored a bag of such parts for about 10 years and upon retrieval, found that the bag smelled of oil. So for reliability I would not use such parts if DC voltages are involved.

atmasphere's avatar
atmasphere
11,632 posts
 

@yowser I've worked with the V-Caps a lot. The Copper foil series is audibly superior (and measure better as well). Given how you're going about this the cost differential seems irrelevant.  I do feel compelled to point out however that as coupling caps the copper foil caps are better than the ODAM parts (which are quite good). You might want to rethink this.

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