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Tube issues Mumbo jumbo?

Hello

I am trying to decipher the jargon associated with some tube data sheets as the info applies to one tube and it’s closest variants.

Namely the 6SN7 – 5692, primarily so the appropriate replacement can be selected for a BAT VK 60.

The problem I think stems from info BAT provided me regarding initial start up and biasing process the amp does all by itself. Their recommendation is to use those tubes which are rated at 600v plate voltages. The 600v is applied only during this startup process, and for only a minute or two or at some point during it.

Perhaps I’m missing something somewhere and it wouldn’t be the first time either… but I can find no 6SN7, 6SN7GT, 6SN7GTA, 6SN7GTB, OR 5692 with 600v plate voltage specs. Using Duncan tube data sheet, Vacuum tube Museum, and a couple other spots I don’t recall the names of… none show that high a level Va capacity. I did see one type listed at 450 Va… but I've seen none showing a 600va ability.

Is there such a thing? I’m figuring at least the sovtek 6SN7 that BAT supplied with the amp possess such a rating, yet I see no info that supports it as 600v either.

What’s going on?
blindjim
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blindjim OP
3,092 posts
 
Jeffreybehr Well thanks a bunch especially for the review.

the idea about the 600v was told to me over the phone by a BAT tech when I was inquiring about tubes and their cost fi retubed using all BAT tubes. $490, plus ship BTW.

I specificially made mention of the 6sn7 not the output tubes... but ya know, the tech may just have mixed up the two come to think of it.

that sure is a dramatic price diff from $150 to $40. Per pair? ...or each?
jeffreybehr's avatar
jeffreybehr
805 posts
 
Obviously I'm not seeing the BAT material, but BAT has to be addressing the OUTPUT tubes, not the frontend tubes. Various versions of the 6SN7 are rated for higher Voltages than others, but I've never seen an audio-equipment manufacturer write anything like that about 'N7s.

Buy what you want to hear and don't worry about your 'N7s' Voltage ratings.

FWIW, my favorite 'N7 is the Tung-Sol RoundPlate, and 2nd is the Ken-Rad. Both are slightly warmly balanced, NOT bright but have high-quality treble, and more spacious than the average 'N7. To my ears, the TS-RP is slightly more-spacious sounding than the KR, so of course I spend $150 for them instead of $40 for the KRs. No one ever said we audiofools were logical.
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sc53
718 posts
 
Email Charlie at Vacuum Tube Valley--he will answer you right away, even on weekends, and knows EVERYTHING. I just ordered a ($$$) quad of NOS Sylvania 6SN7's from him for my Cary SLP98.
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