New Power Tubes for SVT 2 PRO

[slapstick13]

So, my svt 2 pro is currently in the shop getting all new power tubes. I got the amp used last May from a guy who was the 2nd owner of the amp so god only knows how old the tubes are/how many hours are on them. They may have been pretty dead the whole time Ive owned the head.

My question is, what should I expect out of a brand new set of power tubes? Do they take time to break in or should I be blown away immediately? Very excited over here

[JimmyM]

honestly, i don't know how much you can expect out of new power tubes if you're replacing tubes that were fine before. age is not a factor...i've got a few tubes that are very close to having 40 years worth of regular use and they're still in great shape. a good biasing can often take care of a lot of problems with power tubes as easily as replacing them all. this business about tubes needing to be replaced regularly was thought up by a tube reseller to sell more tubes and was adopted as gospel because he wrote a book. replace when they quit working, and keep them as long as you can...that's my motto.

[slapstick13]

Well these NEEDED to be replaced 2 went out and I had teh worst crackling noise coming from speakers. So my tech tested them and said just get a whole new set of 6. So hopefully I can hear improvement!

[JimmyM]

oh, that's different. well you can expect the crackling to go away tonally i think pre tubes will probably give you more of a change, but once he installs them and biases it professionally, you will probably notice a change for the better.

[Billy3000]

Sounds like your amp did exactly what my SVT2 pro did before I got the power tubes changed. I didn't have enough money to do pre amp tubes and power tubes at the same time, so I only did the power tubes since they needed to be done. And MY GOD! The sound blew me away at first. My tech told me my amp was a mess from the previous owner though. I bought it from a music go round store that apparently only fixed it enough to keep it working for a couple months. Both of the transformers were loose inside, one of the power tubes had been broken off inside the socket, another one was disconnected entirely, and the other 4 were in terrible shape. my tech said I had been running on half power the entire time I owned it. To get the volume I needed I had been running the master at about 8, and with the new power tubes I'm often overwhelmed and getting yelled at by my bandmates if I have it on 3!

You'll definitely notice an improvement from new power tubes. Preamp tubes will help a lot too, but if your power tubes were problematic you'll definitely notice a huge improvement!