I've never owned a JJ that lasted longer than a year, and their 12dw7's are garbage. Sonically, pretty good, though. A little dark on the very tippy top, but it works in an SVT for me.
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Need CL help
- Thread starter Floyd Eye
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Well metal guys, such as those on the Carvin forum and TGP love the hell out of them in their guitar amps.
Me, the newest tube in my guitar amp is over 40 years old.
Thought about rolling some 12AX7s/12AU7s in the SVT. I got a stash of old good ones. Amperex Bugle Boys, Mazda, Telefunken, RCA. Kinda want to keep them for my guitar amp though.
They are a cut above the Sovteks almost as good as the US 6550As, the 6550Cs arguably surpassed the 6550As but the heater current draw was higher. If the heater windings on the PT or heater transformer had no trouble with the increased draw it matters not.
I got my tung sol reissue 6550 set from them. Still fine after a few years. I did see those tubes you mentioned and was tempted, but i dont know much about them and my amp is still sounding pretty strong.
If it aint broke...
Let us know how those tubes end up sounding.
I got the new tubes and put them in today. Amp is dead quiet and sounds great. They do break up a little earlier than the stock Sovteks. I really like them. My only issue now is the left bank green LED won't come on. It flickers when I am playing and dig in, but I can't get it to stay on. Other side is fine.
Do those heads have the little points to stick a dmm lead in there?
If so id just bias with a dmm.
If so id just bias with a dmm.
in that case i'd take it in, don't want to kill a new tube if you have a minor problem in there...
As to the iffy LED, it could be a bad LED, a bad solder joint or something wrong with the bias/dianoisic circuit ... if you get it serviced by someone who really knows the CL-SVT, it will sound great ... I view it as money well spent ...IMHO
If it were me, I'd use it and not give it a second thought until it quits working again
Almost what I told the OP in a PM. Use it for his gig then get her checked out later, I don't believe there is any major problem here.
I played it for 4 hours at rehearsal last night. No problems. First I cleaned all the octal sockets with DeOxit and switched the tubes to the opposite sides ( entire trios obviously). Still the same side won't go green, so I don't think it's one of the tubes being out of spec. I'm hoping it just needs a little fine tuning bias wise. I will let the guys at LS Electronics figure it out after the weekend gigs.
As far as the tubes go I am extremely pleased. With any luck I'll get a few years out of them.
As far as the tubes go I am extremely pleased. With any luck I'll get a few years out of them.
Those are the folks that Jerrold Tiers recommends IIRC, they will take very good care of you and your baby. 
OP, given the inability to bias, you most likely blew a screen grid resistor. This is the almost sure outcome of a calamitous tube failure, especially if you have the 1/4 watt resistors in there. I guess it's also possible you got a bad new tube.
