Little Dot Tube Amps: Vacuum Tube Rolling Guide
May 29, 2013 at 4:38 PM Post #1,426 of 13,414
Quote:
Mordy, OK so you had tested the "final" O-getter version of the TS 6AV6 and found them underwhelming. Interestingly, the only "triode" I've tested that convinced me that it was worth it to continue investigating is a 6AV6, which sounds dramatically different from the "pure triode" I tested, hence my question about the Tung-Sol tubes.
 
Acapella, that's pretty fascinating to have such a huge and obvious customs label stuck on a tube lol
 
mab1376, for -DR tubes, as I've mentioned to a few people here in private, reports are that "something" changed in the factory in 1984, independently from political factors -a metal alloy metal machine was sold for scrap apparently- which slightly changed the production of tubes. So, tubes from 1979 to 1983 would be my recommendation, just to make sure you get the best bang for your buck. This being said, most of reviews of 6N30P-DR tubes on the web are of post-1984 tubes, mainly 1986 and 1988 -for some obscure reason- and people still seem to be quite ecstatic about them, and I'm pretty sure they tell the truth (unlike 90s -DRs which are a scam apart from hypothetical '90 to '92 production). I would still aim for the earlier ones, if only for the reselling value and potential better audio quality just in case. If you want to "invest" you could get a quad of tubes, as it is harder to fake.
 

Great info, I'll keep that in mind. unfortunately $250 for a set of power tubes is outta my reach.
 
I would be willing to spend about $100, but like you said, I would want know I'm not missing out on something greater by buying a post-'82-'83 tube.
 
May 29, 2013 at 7:18 PM Post #1,427 of 13,414
some information from http://www.aca.gr/index/hiend/hiendArticles?row=1988 about:

recognizing 6H30 - 6N30 tubes

 

This article is about how to understand and recognize 6H30, 6N30 tubes...

Back in mid 1990’s Mr. Victor Khomenko, founder and owner of Balanced Audio Technologies (BAT), adopted an unknown till then small Russian dual triode tube to update his VK50 pre amp to SE, the 6H30DR...
He had done this due to this tube’s advanced specs that were long different and quite better than the other most common Russian tube 6922, so he called this tube ‘Supertube’... And he was right... 6H30 has Amplification factor 15, Plate resistance 200 Ω, Transconductance 72 mA/V and it is very linear...

As time goes by

After that time, many hi-end manufacturers developed machines based on 6H30, with excellent results, so this tube became very popular and regarding the military Russian version DR, very expensive… Audio Research, Ayon, Consonance, Conrad Johnson, Mod Wright, Cary, Tenor and lately Greek hi-end company Trulife Audio (TLA) are some of them...

Original Russian 6N30's Dr's ... Up left blue-yellow box, Up right bulk white box, down left green box

And Some More


In 1992 Reflector Plant was closed so the production of 6H30DR stopped… BAT claimed that bought the total stock of all the existing tubes, the old military version DR’s...
In 1999 Reflector Plant was bought by Americans and the production of 6H30 started again… The early tubes were of extremely poor quality, they have not reached an acceptable level until around 2004… After that time point, the new production 6H30’s are of a good quality, most of today’s hi-end machines sound excellent with them...
New tubes come today in two versions… The ‘Sovtek’ 6H30 pi EB and the ‘Electro Harmonix’ 6H30 pi EH ‘goldpin’… These two versions are from manufacturing view and in sound field exactly the same...
New tubes as mentioned above are of good quality, but have never reached that of NOS pre 1990 DR’s in reliability, duration and sonics… On the DR’s data sheet is clearly mentioning duration of 10.000 hours and almost every tube has on glass the ‘OTK’ military periodic check!!! That’s why price have rise so high and that’s why some cunning people rebrand them to look like NOS DR’s...

The New Production Russian 6H30's...

a) Electro Harmonix 6H30 Pi EH gold pin

b) The Sovteks 6H30 Pi EB

Recognizing original NOS DR's

So the point is, if someone wants today to use those excellent ‘old time’ Reflector 6H30 DR’s, how is going to recognize them and NOT get fooled to pay a ton for fake ones...
Many people ‘wrongly’ state the paper box, the labeling and the color of text in recognizing original DR tubes… Many others also claim that OTK marking make a tube NOS… This is NOT true… There are NOS tubes in green box, in yellow-blue box and in white bulk box… They are all ok… Also there are NOS tubes with the Reflector sign or not, with black or gray text… That’s ok too… Also, it is very easy for someone to stamp an OTK mark on a new production tube...

As I have searched and studied for a long time the 6H30’s and I have also bought many of them, I have found three (3) significant points that someone can verify a NOS 6H30DR...

The deferences

  1. The plate flaps... in NOS DR tubes are of smooth coloring, exactly same with the rest plate material, with NO shinny line defects as the new tubes
  2. The hat type getter... is much bigger in NOS DR’s than the new tubes
  3. The lettering on the mica under the plate does not exist in the NOS DR tubes (at least in those I have examined)

The real NOS babies

two original 6H30 DR's...

And today's good kids

one new production 6H30 Pi EB

In the end

Today's production 6H30 tubes are of excellent quality and in an affordable price... You can use them in today's hi-end machines... Depending on the written above you can examine the existing 6H30 tubes in your machines to verify if they are original NOS...
Also, if you wanna play with NOS DR's, you can pay attention to the above article... Keep in mind do not buy 6H30DR tubes if they don’t fulfill the above description... And be very careful on some near east sellers on ebay who want you to make themselves rich by selling rebranded tube monkeys...
behind all fake DR's... look at the signed plate flaps!!!



 
May 29, 2013 at 7:45 PM Post #1,428 of 13,414
Quote:
some information from http://www.aca.gr/index/hiend/hiendArticles?row=1988 about:

recognizing 6H30 - 6N30 tubes

 

This article is about how to understand and recognize 6H30, 6N30 tubes...

Back in mid 1990’s Mr. Victor Khomenko, founder and owner of Balanced Audio Technologies (BAT), adopted an unknown till then small Russian dual triode tube to update his VK50 pre amp to SE, the 6H30DR...
He had done this due to this tube’s advanced specs that were long different and quite better than the other most common Russian tube 6922, so he called this tube ‘Supertube’... And he was right... 6H30 has Amplification factor 15, Plate resistance 200 Ω, Transconductance 72 mA/V and it is very linear...

As time goes by

After that time, many hi-end manufacturers developed machines based on 6H30, with excellent results, so this tube became very popular and regarding the military Russian version DR, very expensive… Audio Research, Ayon, Consonance, Conrad Johnson, Mod Wright, Cary, Tenor and lately Greek hi-end company Trulife Audio (TLA) are some of them...

Original Russian 6N30's Dr's ... Up left blue-yellow box, Up right bulk white box, down left green box

And Some More


In 1992 Reflector Plant was closed so the production of 6H30DR stopped… BAT claimed that bought the total stock of all the existing tubes, the old military version DR’s...
In 1999 Reflector Plant was bought by Americans and the production of 6H30 started again… The early tubes were of extremely poor quality, they have not reached an acceptable level until around 2004… After that time point, the new production 6H30’s are of a good quality, most of today’s hi-end machines sound excellent with them...
New tubes come today in two versions… The ‘Sovtek’ 6H30 pi EB and the ‘Electro Harmonix’ 6H30 pi EH ‘goldpin’… These two versions are from manufacturing view and in sound field exactly the same...
New tubes as mentioned above are of good quality, but have never reached that of NOS pre 1990 DR’s in reliability, duration and sonics… On the DR’s data sheet is clearly mentioning duration of 10.000 hours and almost every tube has on glass the ‘OTK’ military periodic check!!! That’s why price have rise so high and that’s why some cunning people rebrand them to look like NOS DR’s...

The New Production Russian 6H30's...

a) Electro Harmonix 6H30 Pi EH gold pin

b) The Sovteks 6H30 Pi EB

Recognizing original NOS DR's

So the point is, if someone wants today to use those excellent ‘old time’ Reflector 6H30 DR’s, how is going to recognize them and NOT get fooled to pay a ton for fake ones...
Many people ‘wrongly’ state the paper box, the labeling and the color of text in recognizing original DR tubes… Many others also claim that OTK marking make a tube NOS… This is NOT true… There are NOS tubes in green box, in yellow-blue box and in white bulk box… They are all ok… Also there are NOS tubes with the Reflector sign or not, with black or gray text… That’s ok too… Also, it is very easy for someone to stamp an OTK mark on a new production tube...

As I have searched and studied for a long time the 6H30’s and I have also bought many of them, I have found three (3) significant points that someone can verify a NOS 6H30DR...

The deferences

  1. The plate flaps... in NOS DR tubes are of smooth coloring, exactly same with the rest plate material, with NO shinny line defects as the new tubes
  2. The hat type getter... is much bigger in NOS DR’s than the new tubes
  3. The lettering on the mica under the plate does not exist in the NOS DR tubes (at least in those I have examined)

The real NOS babies

two original 6H30 DR's...

And today's good kids

one new production 6H30 Pi EB

In the end

Today's production 6H30 tubes are of excellent quality and in an affordable price... You can use them in today's hi-end machines... Depending on the written above you can examine the existing 6H30 tubes in your machines to verify if they are original NOS...
Also, if you wanna play with NOS DR's, you can pay attention to the above article... Keep in mind do not buy 6H30DR tubes if they don’t fulfill the above description... And be very careful on some near east sellers on ebay who want you to make themselves rich by selling rebranded tube monkeys...
behind all fake DR's... look at the signed plate flaps!!!

Very interesting thanks 
 
May 29, 2013 at 10:06 PM Post #1,430 of 13,414
Quote:
After reading that I'm tempted to try some of the EH 6H30Pi tubes.
Not that I have 6N30P-DR's available for comparison.

I bought those EH6H30Pi gold pins about 6 months ago for $27.00 each at 20% off at Parts Connexion in Canada.if i remember it was a very noticeable change especially the power right off the bat compared to the 6N6P-I 
 
May 29, 2013 at 10:16 PM Post #1,431 of 13,414
Where can i get the voskhods from for a good price?
 
I saw a pair for 36 dollars but it seems a tad pricey to me 
size]

 
May 29, 2013 at 10:34 PM Post #1,433 of 13,414
Quote:
Where can i get the voskhods from for a good price?
 
I saw a pair for 36 dollars but it seems a tad pricey to me 
size]

 
I purchased two pairs from this vendor:
 
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=130436695928&ssPageName=ADME:L:OC:US:3160
 
$3.00 a pair plus $12.00 shipping for a total of $15.00.
 
May 30, 2013 at 5:23 AM Post #1,434 of 13,414
Quote:
Today's production 6H30 tubes are of excellent quality and in an affordable price... You can use them in today's hi-end machines... Depending on the written above you can examine the existing 6H30 tubes in your machines to verify if they are original NOS...
Also, if you wanna play with NOS DR's, you can pay attention to the above article... Keep in mind do not buy 6H30DR tubes if they don’t fulfill the above description... And be very careful on some near east sellers on ebay who want you to make themselves rich by selling rebranded tube monkeys...
behind all fake DR's... look at the signed plate flaps!!!

 
Mojorisin is exactly right about the plate flaps, which were the only "inner" part of the tube I had noticed was consistently different between -DRs and new production, though I hadn't had that many new ones, so I couldn't really be sure. New production flaps have visible signs of tooling and aren't the same uniform color. Thanks for confirming that, it's always good to have solid evidence when buying $250+ tubes!
 
"Near-East sellers", you got that right... These guys have been trying to sell 1999 "-DRs" on and off for a while now; on some auctions they sell pretty and old -DRs -which are probably real for all I know- and on others (like tube packs for specific preamps with a quad of 6N30P and an extra tube) they discretely add 1999 fakes -without mentioning it of course... So, yeah, I'd be a bit careful with these sellers, especially considering they have like 3 different auctions and prices for what are supposed to be the same tubes, which just strikes me as odd (one of these has the cheapest price too obviously).
 
May 31, 2013 at 2:30 AM Post #1,436 of 13,414
Just as a general note on Soviet era tube technology-
 
Tubes intended for use in military equipment-sonar buoys, weather balloons, etc., were designed by and large for high stress, long life environments. The Old Soviets were very concerned about making equipment that would survive an EMP and keep on ticking.
 
Junk was simply not tolerated in the military (aside from some blunders like putting a nice hardwood deck on a VTOL aircraft landing pad. :-0) in the 1970's.
 
Soviet gear was in general bulletproof, clunky, stable and of surprisingly good design with high tolerances for abuse.
 
And I say that as someone who was professionally concerned with sussing out their intentions while stationed overseas.
 
Though their nuclear subs did sound like toilets being flushed if one put their ear to a bucket in the ocean while a boat passed underneath. :)
 
I run Soviet milspec power tubes in my LDIII. These do seem to be an improvement over the stock set David provides.
 
May 31, 2013 at 7:53 AM Post #1,437 of 13,414
Quote:
anyone tried a CV850 (EF95 family I think), not a tube I know as the CV4010 (M8100) is far more available?

 
You might want to read a post by Audiofanboy, #1314, page 88 regarding CV tubes. In short, CVxxxx tubes, with four digits, are newer and considered to be better than the older CVxxx tubes with three digits. So while I have no experience with the CV850, the CV4010 is very likely superior.
 
May 31, 2013 at 7:59 AM Post #1,438 of 13,414
Quote:
 
You might want to read a post by Audiofanboy, #1314, page 88 regarding CV tubes. In short, CVxxxx tubes, with four digits, are newer and considered to be better than the older CVxxx tubes with three digits. So while I have no experience with the CV850, the CV4010 is very likely superior.


Yeah the CV number for EF95 tubes are likely the best textbook example of how CV types worked as I wrote previously.
 
Just note that -as far as Mullard tubes go- you can find different versions of the CV850:
 
- Whyteleafe A factory CV850, with a D-getter, sounds pretty dry and large, unlike the CV4010/M8100
- Mitcham factory CV850, O-getter, sounds like an inferior CV4010/M8100 but has similar characteristics as far as warmth and musicality go, pretty good tube as far as I remember
(-Mitcham factory CV850, D-getter? I'm sure I've seen one before...)
 
I actually have 2 pairs of Mitcham CV850 and 1 pair of Whyteleafe CV850, if anyone is curious to try them, as I am doubtful I will ever use them at this point.
 
May 31, 2013 at 10:23 AM Post #1,439 of 13,414
Hidden in the middle of a previous post (post #1389), I have included some information for Russian tubes including information from post 19 in this thread: http://www.diyaudio.com/forums/tubes-valves/138426-6n6p-vs-6n6p-i-2.html. Some of the bits in this thread may be useful to read. The discussion is about 6N6P vs. 6N6P-I and includes details about 6H30P tubes as well.
 
 
PS: Actually, I would suggest reading the thread anyways. For a thumbs up of the impulse tubes ("I"), check besides others posts 35 and 36. Also, check out post 48, quite interesting.
 
May 31, 2013 at 10:55 AM Post #1,440 of 13,414
Quote:
Hidden in the middle of a previous post (post #1389), I have included some information for Russian tubes including information from post 19 in this threat: http://www.diyaudio.com/forums/tubes-valves/138426-6n6p-vs-6n6p-i-2.html. Some of the bits in this threat may be useful to read. The discussion is about 6N6P vs. 6N6P-I tubes.
 


And again, a mention of some "alloy making machines" being sold for scrap by the time Gorbatchev was there, and thereby changing tube quality forever.
 
I need to find that post -I believe by Victor Khomenko, the man who brought the 6N30P tube to the Western world- on some forum somewhere, where he explains the reports by factory workers of of those alloy machines being sold for scrap, and therefore the reason why 6N30P-DR might sound different or be of lesser quality after 1984 -notice how I emphasize the word might.
 

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