Which cap for the Musical Machine?

[BoilermakerFan]

I'll set the upper end of the budget at $15 each. I'll upgrade to NOS Jupiter PIOs or oil cans later if I feel the need to extract a little more performance out of the amp.

I'm currently considering the Mundorf RXF, Obbligato Gold Premium, or the Mundorf RXF-Oils.

Out of the three above, which one sounds better or is the most transparent?

Are there any others in the $15 or less range that I should consider?

I'm planning to build the 6GK5 version with either a SS PS or a hybrid SS like JCM's Silbatone rectification scheme. OPTs will be either Edcor 8.6Ks or custom SumRs at 9K.

[boywonder]

Originally Posted by BoilermakerFan

Are there any others in the $15 or less range that I should consider?

Russian teflons (Ebay) for around $6/ea. if you have the space.

I'm running .22/600V Auricaps in my 6GK5/EL34 MM, and I'm very happy with it, although I have not tried anything else. I have some Russian Teflons, but there is little room left under the hood and they are big.

I breadboarded the amp with the Russian Teflons, and they sounded great as well, but I didn't do much critical listening since it had a fair amount of hum.

[Bruce Anderson]

Just my 2 cents, but I use Russian .22 1000V PIO caps in parallel with .056 600V teflon for coupling in my 6GK5 Machine and I like it a lot. At least at one time Poinz said the 10K Silk was about as good as it gets for an output trannie for this amp and again, I'm happy with that choice. This is a wonderful amp for my Lowthers.

[HornTube]

If you want rhythmical correctness never use caps in parallel! If you add a small cap to a big cap you will change the speed and the texture of the highs. It is only good for caps sounding difficult in the highs like Solen.

The Obbligato Golds are rather warm & transparent. The Russian teflons are very smooth & detailed but lacking in authority & real bass. The Obbligato Copper case caps are VERY detailed and analytical - dangerous stuff. Mundorfs are very transparent, neutral and speedy.
Personally I prefer the bullet proof, anti-nazi, north pole & atomic-bomb proof Russian K75-10 or K75-24 hybrid caps. They are =H_U_G_E=. Rather warm but also transparent showing myriads of textures never ever heard before. A slight tendency to rose tinted glass. I'm totally addicted to this stuff and love them eternally, even the Mundorf Sliver PIO's had to go... Even bad sounding CD's are listenable now.

[aardvarkash10]

rose-tinted transparency and the capability to make bad recordings sound good.

Aie aie aie...

[mark02131]

Originally Posted by Bruce Anderson

Just my 2 cents, but I use Russian .22 1000V PIO caps in parallel with .056 600V teflon for coupling in my 6GK5 Machine and I like it a lot. At least at one time Poinz said the 10K Silk was about as good as it gets for an output trannie for this amp and again, I'm happy with that choice. This is a wonderful amp for my Lowthers.

Poinz uses Jenson Caps you can get them form Sophia electric but there $30 each so $15 over what you want to spend.

Why did you go with .22 and not the .33 that poinz uses? that affects the low cut off frequency right? does it put it below 20hz.

[Alastair E]

Just use a good quality Hermetically sealed PIO like the K40Y-9

K75 were intended for PSU/mains filtering --thats why they are marked, 50Hz....

All the others are just audiofoolery IMHO....

[Eli Duttman]

FWIW, PTFE film has reputation for transparancy and requiring extensive run in time.

Soviet surplus, either PIO or PTFE, is where the value can be found.

[mor2bz]

I got auricaps in my PP 6V6 and I do like them. Poinz was not super impressed with them however and is IS the man

what about some nice sonicaps? I have never tried the Russian stuff.

[Bruce Anderson]

Actually, I misspoke Mark. I use two of the .22 PIO and one of the Teflon, a little bigger than Poinz recommended.