Teflon Coupling Capacitors 0.1 0.2uF for tube Amps

[Perfectusaudio]

Hi, I am looking to start a new thread, on 0.1 uf and 0.22 uf Teflon Coupling Capacitors and any other 0.1-0.2uf suggestions for tube amplifiers under $60 USD each

The Russian FT1 FT3 K72 and now Solen SQ3 series all fit this category.
I am sure their are others and wonder what results people have had with these .
Their are Blogs comparing the FT1 FT3 and K72 to Vcaps but wonder how others have found them in coupling positions between say a driver tube and out put tube ie 6SN7 > 2A3 /300 single ended , or E280F > 2A3 /300B , Ra, CCS or Choke loaded

 

[RajkoM]

This is a matter of taste.
I have tried russian K72 teflon caps in my C3g-300B and E180F-6C33C SETs (CCS loaded drivers both). I could not wait for the "few hundred hours of break-in time" as some DIYers recommend for teflon capacitors.
I finally decided for Siemens MKV (B25839 axial capacitor) as coupling.

K72`s I have modified for the RIAA network.

 

[euro21]

I use -for years- 0.22uF FT-3 in my #26 preamp output ... parallel with 0.1uF tin foil V-Cap ... as parafeed cap to my TVC. I'm happy with it, the tonal balance is satisfying.

 

[Perfectusaudio]

interesting comments thanks
Has anyone done a direct comparison between Vcaps and Russian Teflons?

 

[randytsuch]

Here are some cap reviews for you
Capacitor Musings Article By Jon L DIY Audio Kits Reviews

Russian teflons and vcaps are in the mix, along with a host of others.

I also read somewhere that the Russian caps sound better if you cut the case off, stick them in a new case with better leads. Never got around to trying it.

 

[analog_sa]

The only teflons i've tried are FT3 and Sonicap Platinum. Hated both, especially the russians, which were just awful in my system.

Whenever possible i try to avoid coupling caps but if avoiding them is too hard my choice goes for Clarity MR, Mundorf S&G or ancient Bosch MP. Yes, they all sound very different, but unlike the teflons excel at communicating music. None of which means the VCaps are not excellent.

 

[analog_sa]

I also read somewhere that the Russian caps sound better if you cut the case off, stick them in a new case with better leads.

Tried that too with the single Ft3 type i had: 0.22/600. A very minor improvement.

Btw, the Sonicaps had an incredible extension on both ends compared the the FT3. Midrange presence too. But overall tiring and unnatural.

 

[Perfectusaudio]

I have now got K72/FT3/to try in a new E280F/300B amplifier

Will gather Audio Club Members and also try Russain Paper K40Y and oil

Dearborn / Sprague V710P/730P that Yamamoto insert into bits of wood
Audio Cap Theta

Solen SQ3

And see what happens
Will use Electra-Print Iron I have spare and also Amorphous Double C core .
I tried Nanocrystalline-Finement from Teramoto in a 2A3 but it was hyper detailed in the mids and top end not for all tastes, the old M19 Electra-Print has more bass than any i have used so far and even sound top to bottom.
The Amorphous had a lovely balance through out .

Sorry digressed away from Caps

 

[Perfectusaudio]

Hi, I have opened up the thread to any other 0.1 - 0.47uf coupling capacitors, so as to not restrict comments as I believe this will be a useful thread for many to comment on.

 

[JMFahey]

I also read somewhere that the Russian caps sound better if you cut the case off, stick them in a new case with better leads.

 

[Kay Pirinha]

I also read somewhere that the Russian caps sound better if you cut the case off, stick them in a new case with better leads...

...and write something like Mundorf or that on them, eh?
Best regards!

 

[Osvaldo de Banfield]

The problem is them sound in russian

 

[Kay Pirinha]

So one may prefer listening to balalaikas or Kozachok music to exploit the full potential of these capacitors .
Best regards!

 

[RajkoM]

I removed the case just to unwrap Al foils and teflon insulation and make capacitors exactly value for RIAA network.
Wonderful teflon insulation I used for DIY my own OPTs for 6C33C SET; layers between primary and secondary windings together with paper/mylar insulation.

 

[Osvaldo de Banfield]

In my case, although I can't understand any word in Russian, there is a very interesting Russian Jazz Band that sounds very good.

 

[anatech]

Hi RajkoM,

I removed the case just to unwrap Al foils and teflon insulation and make capacitors exactly value for RIAA network.

I would be worried about changing the tension in the wrap and possible unwinding in the future. Neat idea, but I just buy the correct values, or use combinations to make them up.

-Chris

 

[analog_sa]

Rajko's idea allows to use a single capacitor without involving additional dielectric types. If one insists on teflon it is a brilliant idea. The FT3 i once opened is pretty loosely wound, so no danger of spoiling anything.

Curiously, quite recently used the teflon film for a low pf value diy capacitor using copper clad pcbs as stators. Despite the minimal amount of dielectric the "teflon" sound remained.

 

[anatech]

Hi analog_sa,

The FT3 i once opened is pretty loosely wound

Really?? A loose wind could give rise to all kinds of effects. I've never opened a capacitor and found it was loose wound.

I do agree that this method is inspired, but I can't get past possibly changing other parameters eithert immediately or later on because the capacitor was disturbed.

-Chris

 

[RajkoM]

Hi Chris,
The K72 capacitor is "free" in the steel case. When you remove the casing, there is no possibility of changing tension or other parameters except value. For sure.
You have to be a little careful and neat, of course.
I did it a long time ago. I tried other capacitors in RIAA preamp. Siemens styroflex is excellent, but I've always returned to my modified teflons.

Best diying

 

[Perfectusaudio]

I popped the Dearborn / Sprague V710P/730P capacitors Yamamoto use into a pre amp and the 730P metalised had quite a bit more bite on leading edges of Cymbals and Female vocals , the Long run alloy foil V710P was more balanced top to bottom , but the FT3 was much smoother and neutral sounding, a way better capacitor IMHO ,admittedly the Spragues were not inserted into ebony wood cases, not sure if this actually achieves anything?