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Epi Galaxy 10 w/KT66?

12/23/2005 4:06 PM
Epi Galaxy 10 w/KT66?
I got an Epi Galaxy 10 last week - great deal from MF. I put a Mullard 12ax7 and a CBS 6L6GC out of an old Bogen I have and WoW - what an improvement I happened on a pair of NOS KT66's with straight bottles and after reading about these on the net I installed one. An even bigger, fatter sound & boy was I loving it till the amp started to hum loudly so I shut it off. In the morning I turned it on standby and when I applied power the fuse blew. I put the 6L6 back in and a new fuse and it's fine. Does anyone know how these amps are bias'd? Do the KT66's need a bigger power tranny? I'd really love to run this tube in it the tone is killer!!! Any help will be appreciated.
12/24/2005 5:15 AM
Chris/CMW amps

Hi Mike  
The KT66s do take more filamentcurrent (1.27A - 1.5A from top of my head) than 6L6s (0.9A).  
If the biasing and screengrid-circuit are ok then I do suspect the PT for having not enough power to feed the KT66-filament.  
If this is the case (be sure to try the KT66 in another amp) then you could install an extra OT giving 6.3Vols at 3A.  
Hope this helps/merry Xmas tweaks,  
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12/24/2005 7:17 AM
Chris/CMW amps
oops, did mean PT not OT!
12/25/2005 9:51 AM
Dan Theoret
Re: Epi Galaxy 10 w/KT66?
I've never heard of a straight bottle KT66,but have heard of and seen old Russian 6l6(sort of) straight bottles relabeled as "KT66" and "made in England" they were not the same as a 6l6gc or a true KT66 and this could possibly have caused your problem.  
This amp is most likely cathode biased and set up for a normal 6l6gc.  
just my 2 cents worth.  
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