Russian PIO caps. Should I use them?

Re: Ot

yagoolar said:
I praise my Russian classes in primary and secondary schools!!!

BTW, I own some Polish caps made by Telpod marked KBG-MN based on Russian GOST norm. Seems they were "licensed".

Unfortunately my parents did not teach me to speak Polish, they spoke Russian only...

KBG are capacitors made of a paper and a foil, hermetically sealed (soldered), with glass insulators. Nice caps. However, ftoroplast and silver-mica caps beat em sonically...
 
rdf said:
If the SGM are equivalent to the SSG silver mica I believe one forum member described them as embedded in wax.
I opened one SGM3 (light green ceramic case). I don't know if there was vacuum inside :) but the metalized mica sheets were held together by some oily substance. The case was not filled with oil. I use them in passive RIAA equalizer.
 
They are marked ÌÃÁ4-1. Is that good
Not so good.
Caps MBM, MBGO, etc. series - really cheap, but have bad electric parameters. I consider that they are made for work in big range of the temperature, but dielectrical loses really big.

And here is review from my customer from Australia about FT-3 teflon caps:
Teflon capacitors FT-3 have unmeasurably low dielectric losses and absorbtion, have extremely low leakage and quite low equivalent series resistance (ESR) (about 0.04 Ohm, including leads). Tolerance is typically 1.5% though conservatively specified at 5%. These capacitors are exceptionally good for high voltage precision analog integrators, long interval timing circuits, sample-and-hold circuits. In audio applications they are perfect for low frequency filters where precision response and matching is required. As inter-stage coupling in the tube amplifiers these capacitors are capable of delivering ultimately deep, distinct and yet soft and transparent basses.

And well known K42-Y2 / K40-Y9 series: no one did not left bad feedback about this caps. I sell more than 3000 caps this series, and all was complacent by parametrs.

Thanks, Oleg.
________________
http://ussr-tubes.com/
 
The K40s are considered by many to be superior to the K42s sonically. The K42s primary advantage is size, they are much smaller than the K40s.

The K40 is true PIO, most treble, least bass

K42 is metallized paper impregnated in oil, more body, little rough high

K75 is mixed/hybrid of polyester & metallized paper impregnated in oil. K75-10 sounds good, K75-24 not as good, same as K42

K73 is like polyester/mylar, K73-2 is in oil, K73-1x is dry plastic w/o oil

Lar
 
Great thread, thx for this.
Any ideas about those critters?
 

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PythonOleg said:
Metallo-Bumajni-Germetichni-Pryamougolni
Metal-Paper-Hermeticity-Square-wave

[/B]

Pryamougolny means a rectangular form of the body.

:)

"The best" always means compromises, i.e. different losses in different applications for the same capacitors. However, some very expensive dielectrics and metals can be used to make capacitors for all means of usage, but anyway it will mean compromises.

For example, losses sometimes mean thermal changes, thermal changes mean change in sizes, that mean changes of capacitances. It is one example. Some losses are chemical. Some depend on a current, some depend on a voltage. Some mean piezo-effect that changes geometry with voltage. It is always very complex. Now suppose that during an one period of a signal the capacitor changes it's properties several times by several ways...
 
K40-9y

I've compared k40s and film and foil in my pre. K40 will give you more mid. And the film and foil will give you more high (faster) sound. So, what's new? Personally, I prefer K40s, for they give me that heavy sound such as vintage marshal vs modern ss amps. In the end, it's a matter of preference. IMO, K40s sound like some where in between oil and film.

I tried, motor run can in my linestage. Not bad. A bid slow. But it has a merit. Say, if you like 60s guitar sound or cello or sax. This is the way to go.

My subjective opinion that is.

Yaho