• WARNING: Tube/Valve amplifiers use potentially LETHAL HIGH VOLTAGES.
    Building, troubleshooting and testing of these amplifiers should only be
    performed by someone who is thoroughly familiar with
    the safety precautions around high voltages.

From glass to mylar

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I have recently finished these monoblocks.
They are based around this schematic.
The story of the original is here (Dutch only).
What makes mine special are the OPT’s. They were custom-made for me by .AE Europe to go directly from valves to my Electrostatic Speakers thus omitting the speaker’s step-up transformer.
It uses Sylvania 6J5GT, RCA 7N7 and Svetlana 6550’s.
All PSU caps are Bosch MP in oil that I got brand new for €1/each, surplus.
Coupling caps are Siemens/Epcos MKV.
The housing is temporary.
I have been listening to them for a few weeks now and they have worked trouble free from first startup and sound great. I love them :cloud9:
 

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Cool Peter

I was going to ask how you like the Svet KT88s. I have been working with them for a number of years, but lately been testing out the "Svetlana" and EH brands.

In the USA, from my understanding, there is now a difference between the "Svetlana" brand and "C" logo brand. The "C" logo brand is from St. Petersburg and the "Svetlana" brand is manufactured by another company, I believe Sovtek. All three brands, Svetlana, C, EH, look the same, but all three sound different in my rigs.

Thanks Peter.
 
diyAudio Senior Member
Joined 2002
Hi,

In the USA, from my understanding, there is now a difference between the "Svetlana" brand and "C" logo brand.

Yes indeed, Svetlana Electronic Devices the U.S. marketing firm is no longer allowed to use the Svetlana name; they've been sued as they apparently imported from other ex-USSR manufacturers and branded these as Svetlana tubes.
Well, that's what I've been told anyway.

From now on the only Svetlana branded tubes you're going to find in the U.S. will be what's been left on the shelves of dealers.

New stock will either carry the old Svetlana label; a "C" (C=S in latin script) or whatever does not come from the Svetlana factory will be branded as "SED" > Svetlana Electronic Devices.

In Europe matters are different as I understand the Svetlana factory hasn't set up a marketing branch there yet.

Years ago I always dealt directly with the USSR factory's agencies whenever large quantities were involved, mostly 6L6G, 6DJ8s, EL509s etc.

We could do this as we didn't have the embargo on communist product as you had in the States.
Alot of that imported product was ( and still is) rebranded as European product and did pass by the embargo that way.

It therefore comes as no surprise you may find sonic differences amongst the EH - they mostly use a military factory called Saratov- and the Svetlana or Sovtek.

Sovtek is the name used by New Sensor Corp. in NY and was set up by Mike Matthews. No plant by the name of Sovtek exists but NS uses several plants who make a variety of audio and industrial tubes.
NS' main interest is with the music industry so their catalogue carries mainly everything that's currently used in that particular field.


Hope this helps,;)
 
I was going to ask how you like the Svet KT88s
Well, I like them but I haven't tried anything else so that doesn't mean much. (I use 6550's btw not Kt88's)
What is interesting though is that I seem two have two different pairs (both have the C-logo). The first set I bought (unused) from somebody that never finished his own project. They were ordered originally at tubestore.com. The 2nd set I got from triode-electronics.com. And they do look slightly different. Whether or not they sound the same is difficult to say. The tubestore ones do look a little better though.
 
Frank - People mistakenly use name "Saratov" as a lamp's name.

Saratov is the name of the city in which "Reflektor" factory exists (or perhaps it is not in the city, but just in the oblast [=region/province]).

Reflektor is large manufacturer, both in past and present. i understand that they produce a lot of lamps exported under the name "sovtek", and EH as well.. but i am not sure of EH.


I think reflektor is one of the biggest lamp producers, just because a lot of lamps i come across are produced by them (old lamps, from before the sojuz fell apart).

but each manufactuer made more of some type than others.

almost every 6P14P (~EL84) I have seen is Reflektor.

then, some other types, seem almost exclusively made by other manufacturers. probably more efficient for each respsective plant to make 1M x 20 types, vs. 200k x 100 types, and so forth..
 
diyAudio Senior Member
Joined 2002
Hi,

Saratov is the name of the city in which "Reflektor" factory exists (or perhaps it is not in the city, but just in the oblast [=region/province]).

Quite right, Saratov is the capital of the Saratov province.
I've no idea where exactly the Reflektor factory is located though...

Reflektor is large manufacturer, both in past and present. i understand that they produce a lot of lamps exported under the name "sovtek", and EH as well.. but i am not sure of EH.

To really confuse the market and as an example you'll find the same Reflektor made EL34 branded as EH, Svetlana and Sovtek.

In the future the Svetlana brandname for this kind of product not stemming from the St-Petersburg factory will be replaced by SED.

almost every 6P14P (~EL84) I have seen is Reflektor.

Yep. Same here.

then, some other types, seem almost exclusively made by other manufacturers. probably more efficient for each respsective plant to make 1M x 20 types, vs. 200k x 100 types, and so forth..

That's how it worked in the seventies and eighties in Europe as well.
Even to the point that almost of the MULLARD EL34 were made by Tesla in those days....

Cheers,;)
 
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