Tube condition in an SVT

charlyg · Post by **charlyg** » Sat Feb 10, 2007 6:45 am

How do I evaluate the condition of the tubes in my SVT? I don't see many tube testers around anymore!

doctorwho · Post by **doctorwho** » Sat Feb 10, 2007 10:20 am

Charly, I just got a tube tester last week but haven't checked it out yet. If it checks out OK, maybe one of us can make a short trip to check the tubes out.

I still remember taking tubes into a store and using the in-store tube tester for free ...

charlyg · Post by **charlyg** » Sat Feb 10, 2007 11:04 am

Cool! I started another thread comparing heads/cabs on the bass thread. I may not keep the 8x10 very long. The Classic head sounds GREAT with my 4x10! A big improvement over the B2RE. Curiosly, I think the B2RE sounds better than the SVT through the 8x10, at least at home!

rictified · Post by **rictified** » Sat Feb 10, 2007 2:34 pm

Unless you have a really good one like certain Hickoks and other mutual conductance testers they're pretty much useless. The older the tubes get the hotter they run, and the longer they take to warm up. If you ever see one glowing a lot brighter than the rest (which is unlikely in an SVT due to their having a plate resistor which opens with excess plate current) shut it right down.
If the Classic sounds worse in the 8 x 10 it probably has a problem as 8 x 10's are a lot clearer than 4 x 10's and will reveal problems as the head will usually be overpowered before the cab will be.

charlyg · Post by **charlyg** » Sat Feb 10, 2007 6:16 pm

Sorry, I meant it is TOO much with the SVT. I don't have the space for the 8x10 to "stretch'!