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Newproduction power tubes: Reliablity

There  isa topic going on  concerning power tube issues in his PL amp, 
Some of us have power amps with 4-12 power tubes,,  the higher number of the tubes in a amp means the more demand for  reliability.
The 2 countries making  the most power tubes are china and russsia, So basically we can say this is a Russia vs China shootout.

China has come out with incredible numbers of power tubes, varieties and styles. These are the SET tubes. Russia has a  far superior selection in the push pull category.
IMHO , as i do have a  push pull amp, I favor the russian labs as far as reliability. 
Here is where it counts, As we know, its no fun having a   multiple power tube amp, and hearing 1 or more tubes going bad. 
A  good tech is not cheap, nor so easy to locate.
So in terms of reliability/push pull, I have to side with the russian labs.
The one exception on russian power tube relaibility, is the russian KT150,, its a new tube and we have not yet had long term performance testing. It is  not a tube I am the least bit interested in. 
. 

mozartfan
johnss
570 posts
 
have not tried the JJ KT88s or svetlanas, so can't offer any opinion on them. But have tried dozens each of  the electro harmonix KT88 and 6550, the Mullard KT88, and Tungsol 6550 all from Russia. All are pretty reliable, have some sonic differences, Mullards are a bit warmer sounding, EH KT88 a bit more open, etc. The Tungsol re-issue 6550s sound pretty close to the original US made Tungols.

The Shuguang factory has done their homework on plate and cathode construction materials and now understands how these affect the sound of the valve. Shuguang used to make the PSVANE tubes, but now PSVANE has their own factory so is making their own valves.

If you like the sound of the GL KT88s, you may want to try the PSVANE gray glass KT88s, more open, and detailed than the GLs, but will not last as long.

Should also state my amps are not stock. All have Jensen copper foil caps installed in the coupling caps and power supply locations, which also will affect the sonic attributes of the TUT (tubes under test).



mozartfan OP
2,143 posts
 
Mullards are a bit warmer sounding

^^^^^^^^^^^^^^

Thats how me and  1 other  audiophile(quote: *I just didn't care for the GL's*, end quote) found the GL 88's. 
The GL are very popular, but just found the Svets a  superior tube.
have not tried the EH 6550;s.. I just might, ,,sometime after i get all my upgrades paid off/paypal debt.

This way I'll keep either the EH6550s or the Svets 6550.

mozartfan OP
2,143 posts
 
Tell ya what, Just read some of this review,,, read down,, eh655 vs eh88
He prefers the EH88 vs EH6550
so tahts what i will do, instead of getting the 6550 EH I'll buy the EH88 vs the Svet 6550.
Only 1 set will remain.

as i say in this topic, the 6550 and 88 are so close, near identical. 
I'll try adding a  set of EH88's  late next year (paypal debt will be near zero after paying all upgrades, new components) and will posta  review.
p
From 2002
longgg time ago
'https://hometheaterhifi.com/volume_9_2/power-tube-comparison-6-2002.html

mozartfan OP
2,143 posts
 
My problem is right now i have a pair of Sovtek 6922's in the cayin cd player and have muffed the sonics,, This is with my new Seas Thor xovers.. A pair of EH6922's arrive today and will find out just how the new Svet 6550's sound with new xovers, + superior 6922 tubes in the cd player,,also havea Tele pair of PCC88's arriving next week.
So maybe these Svet 6550's are not performing due to low level russian military style 6922's. 
As mentioned in another topic, all 6922's sounded near identical in the Cayin cd17, but when employing a  russian military style 6922, the sonics lowered drastically.


jjss49's avatar
Ag insider logo xs@2x
jjss49
6,612 posts
 
Sovtek makes their tubes in the old Reflektor plant in Saratov... EH is one of their marketing brands, so current 6922’s labeled Sovtek are the same tube as sold by EH

if you want a better sounding 6922 you should look at USA or Dutch Amperexes or Tesla old Yugoslav production ’labelled’ 32... otherwise seek true old stock (not current Sovtek owned brand) Mullard 6922 equivalents called E88CC
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