tubes for leben cs600


hi there.
i look for good tubes for my leben cs600 that connected to my devoe nines speakers .
i dont know alot on tubes i have now kt77 and kind of el34 tubes but they are in the end of them life. igot suggest to buy from jim mcshane and he give me this suggsted :

(1 quad) 6L6GC-STR Tung-Sol reissue, $87.50
(4) 6CS7 - 2 Sylvania & 2 Raytheon/Japan, $38.00/set
(1) 6CJ3 GE NOS USA made, $7.50
but when i try to invite he email me and say that only 2 6cs7 sylvania he can provide because he dont have in is stock 2 more c6s7. so i dont know what to do i most have new stock of all the tubes to my leben ,i wonder to buy from the company leben extacly what they put inside the leben but to order it is about 400$ to israel all the
tubes new, or to buy from jim mcshane the tubes that he have for 120$ besides the 2 6cs7 that he dont have in stock and he dont know if he will have it ,so maybe to buy the two that he miss from ebay bout i dont know what to buy from ebay very confused
please any suggestion about th tubes what you says my friends
thanks alot
bolero32
EL34 and 6l6GCs have pretty different sound signatures so it will be different as EL34 have a lot more warmer lusher sound (Generalising) and 6L6GCs much more bolder and wider across the range (Again Generalising)
for the price the Russian 6l6GC reflector equivalents (6n3c e) are great..they are not expensive and definitely better than the SED6l6GC i used in the past.

But for me..as has been mentioned by Notec, the KT120s are in a different league altogether . the 6cS7s, at least to me do have an impact but its minuscule in comparison and in my opinion, need be on ones agenda only after changing the power tubes.
I only have kt-77 since i bought my leben used.
But i dont wanna play alot with the tubes just wanna know from yours experince what will be the best combinition ?
All i know kt 120 need open the cover of the leben and in my place is inpossible i have kids and its on my furniture table in the center of my living room.
My dealer can send me from japen the original set of the leben and its coast after taxs and shipping to israel 400$ much more expensive then Jim suggestion but i still not understand if the original tubes what leben company put inside the leben will be the mark of leben sound this is the reason that we buy leben or to play with others tubes that maybe will give better sound and much more quality who can say what better the tubes that leben put (maybe they put cheap tubes or standard tubes to save money or they put better tubes from what we put i means the companys and the quality)what will be the better chioce or what the diffrenet in the sound
leben company tubes or Jim suggestion and what better kt77 or the Tungsol 6l6gc-str ???
Please help me understand
the "original" in my case was Sovtek 6L6GC and any new tube was better !
With the KT-77 i would think your sound will be good and that unless you hear different ones , not be able to evaluate any different tubes.

Yes with the KT120 you cannot put the cover back on so that is out . if you are trying 6l6GC the 6n3ce is a far cheaper And better option. I am pretty confident this will be better than the GEnalex KT77 as well ..a s in my case i prefer the larger freq extension of the 6l6GC to the lushness of the KT77 (or EL 34) but individual tastes can vary hence cannot say how it will work for you