Are there any russian capacitors of interest for decoupling, ie 0.1-0.22µF or other goodies for the B+?
Teflon FT-2 (200v stated maximum but can be exceeded according to users, also smaller) or FT-3 (higher voltage) are the ones to go for. Aluminium bodies. I have loads and stack them in parallel as needed. Failing that K-72 steel bodies. Sound pretty much the same.
I don't bother with any other types - love the teflons. Some like the silver mica caps, square brown things, but I prefer the teflons. I don't think the paper caps are worth bothering with.
I don't bother with any other types - love the teflons. Some like the silver mica caps, square brown things, but I prefer the teflons. I don't think the paper caps are worth bothering with.
Along with the FT-2, the K72 pops up. They seem to have teflon cases instead of alu. Any experience with those?
I wil order some FT-2/FT-3 in 100/220nF and 100nF silver micas, not that expensive. Just want to test vs the VTV and Jupiters I still have, as I will need 6 for the retrofit of my EL34 amp. Switching out the ECC83/ECC82 for some rusky single triodes along with =©= EL34s, so might as well use russian caps 🙂
I wil order some FT-2/FT-3 in 100/220nF and 100nF silver micas, not that expensive. Just want to test vs the VTV and Jupiters I still have, as I will need 6 for the retrofit of my EL34 amp. Switching out the ECC83/ECC82 for some rusky single triodes along with =©= EL34s, so might as well use russian caps 🙂
Cases for the K-72 are steel, not teflon. FT-2/FT-3 should do you very well if you have space. I assume that for single triodes you mean 6E6P or 6E5P. Plenty on eBay and still cheap. They sound excellent for indirectly heated tubes.
It looked like some slippery plastic like ptfe or pu in the photos 🙂
Re triodes: Probably not as it is for an existing Art Audio amp, not sure the tranny will pull the extra current of two 6E5P/6E6P tubes. I have plenty of 6E5P and 6E6P-DR so I can definitely try, but rather it will be a tube pulling under 20mA like the 6S4, 6Z9, 6Z11, 6Z49 etc .
It will power my bass cabinets (Altec 515C) and seems like a nice project as this was the first tube amp I ever had (and the only one I ever bought). It's going on 22-23 years, so needs some loving like new e-caps, so might as well overhaul the thing as the inside doesn't look pretty.
Re triodes: Probably not as it is for an existing Art Audio amp, not sure the tranny will pull the extra current of two 6E5P/6E6P tubes. I have plenty of 6E5P and 6E6P-DR so I can definitely try, but rather it will be a tube pulling under 20mA like the 6S4, 6Z9, 6Z11, 6Z49 etc .
It will power my bass cabinets (Altec 515C) and seems like a nice project as this was the first tube amp I ever had (and the only one I ever bought). It's going on 22-23 years, so needs some loving like new e-caps, so might as well overhaul the thing as the inside doesn't look pretty.

The russian KBG-MN paper in oil type may be useful as a first capacitor in a CLCLC power supply. Especially if you dabble with mercury vapour rectifiers or other rectifiers with low internal resistance. I tried them as output caps in a DAC just for fun. I liked them. Smooth, but perhaps a little slow. Just what the doctor ordered if the sound is a little "nervous".
I like K40Y-9 in coupling circuits.
Shhh.... These are a bargain, but need somewhere between 50 and 200 hrs to break in. At the start they can sound pretty dull. After they break in... WOW.
Along with the FT-2, the K72 pops up. They seem to have teflon cases instead of alu. Any experience with those?
The cases are steel. Kind of heavy. Values are smaller than for FT-2 as well. Internally they are supposed to use the same materials though.
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If your looking for a low voltage option the Russian FCH 0.25uf 60v Teflons are superb
I have a bunch in my headphone amp.
I have a bunch in my headphone amp.
Notwithstanding what is said about polyester caps, the k73-16 250V are excellent, as anyone who has actually used them will attest. Also k71-4 and K71-7 polystyrene. For bypassing power supplies I often use k75 although these are rather big, to say the least.
I use K73-16 in tube amps. The only case when I needed Teflon caps, was in S/H for a synthesizer. Also, Electrocube, Vishay, Epcos film caps are great. Also, Y1 and Y2 safety caps are great not only for UL, but also for audio. However, they don't cost impressive, so if you want to impress people, go for teflon, or paper in oil. 😀
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Anatoliy, thank you for reminding me; I have a box of K73-16 630 V that I had completely forgotten about. Also, I have been thinking about building your RH triode Gubernator.
Gubernators are a series of SE amps designed and built by Wavebourn, the schematics of some of which he has generously shared. I've not built an SE amp myself but I've got 3 pairs of SE transformers to use up and since I've always wanted to build a GU50 amp but am too chicken to deal with the voltages for pentode push-pull, this would seem a slightly less formidable construction. Sorry for the off topic!
I still have two of the GM100s here. Thought of making an amp for them once, but don't really need the power and don't want to kill my dog by accident 🙂
Have a link to the Gubernator amps?
I'll order a bunch of 100nF caps in different series, the silver mica ones look cool (never knew they went that high).
Have a link to the Gubernator amps?
I'll order a bunch of 100nF caps in different series, the silver mica ones look cool (never knew they went that high).
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