April 23, 2012
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Saratov 6H23π-EB
These are Soviet made dual triode tubes with production years of 1979, 1980 and 1982 purchased from Upscale Audio about seven years ago. Upscale still has them listed on their web site as the 3rd type (or, “Type 3”) variant and they range in price from $20 each for the Driver Grade to $30 for Gold Grade to $35 for Platinum Grade. Although I no longer am sure, I believe the review samples are Platinum Grade (“Lowest noise and microphony with the tightest triode balance we have available. This is typically 10% or tighter, but may be higher depending on available stock.”).
The 6H23π type is the Soviet equivalent of the 6922 dual triode and was designed, originally, for military and space use. The “EB” variant is supposed to be the ruggedized version and is the more sought after variety.
Standard Arabic numeral designation: Other side showing month of production in Roman numerals (this was abandoned soon after)
The middle fellow in both shots appears to be a little tipsy.
I had not listened to these tubes in my c-j Premier 16LS2 for quite some time and was quite pleased with how the sounded. These followed on the heels of the Mullard PCC88/7DJ8, previously described, and was in many ways quite different sounding. I’ve been using the Saratov 6H23π-EB initially with the vintage Tung-Sol three hole 6550 and currently with the Shuguang GEKT88 (review forthcoming) output tubes in my Premier 11A power amplifier.
Compared to the Mullard PCC88, I found these tubes to have a more natural presentation with an even, linear response across the frequency range. Although the Mullard mated perfectly with the Penta Labs KT88SC output tubes, I thought they sounded tipped up and exaggerated in the treble with the original Tung-Sol 6550s. So, if your output tubes are a little on the dark side, the Mullards are a very good choice in bringing more detail to the front. However, their use with a neutral tube such as the original Tung-Sol 6550 is more iffy and with somewhat lean or analytical tubes such as the SED =C= 6550C or the Ei KT-90, I feel they are too much of a good thing and wouldn’t use them in those combinations.
Listening Impressions:
- The Saratov 6H23π-EB is a definitely more even-balanced sounding tube that lays a solid foundation in the bass. Cellos have a woody quality that I find appealing.
- It has a more subtle presentation of inner detail and, if anything, may be slightly warm in the upper bass and lower midrange.
- Treble presentation is neutral and without exaggeration.
- Lateral separation, height and depth are very good although not as immersive as the Mullard/Penta combination.
All in all, the Saratov 6H23π-EB tubes are a good choice for a neutral sounding tube and although not in the same league as the Lorenz PCC88 (and other vintage varieties such as Telefunken and Amperex) have the definite advantages of being both readily available and very reasonably priced.
NB: These were mistakenly identified in the original posting as Voskhod 6H23π-EB when they are in fact from the Saratov factory. Sorry for the confusion. I do in fact have some Voskhod 6H23π-EB and may report on them in the future.
Comments (2)
Those photos are excellent. Much better than my old scans from the 80s and 90s!
I wonder what the military needed these tubes for. Tubes will still work, when there's environmental radiation, so maybe that's one reason tubes were militarily used until the 90s.
@rpghero27 -
I happen to think that your scans are rendered quite nicely, but thank you for the kind words.
The way I understand it, tubes are immune from the electromagnetic pulse (EMP) caused by nuclear explosions and certain other devices which is why the Soviets used them in certain key spots instead of transistors. It keeps your plane from falling out of the sky after a nuclear blast. Is that what you meant by environmental radiation?