I've got a malfunctioning SVT-VR!

[brekfustuvluzer]

When I turn it on, it takes longer than normal for the standby light to change, and when it does channel one is very quiet while channel two seems unchanged. Does anyone have an idea of where to start? I'm definitely not an amp tech kind of guy, but if it could be a simple fix, i'd like to try to work it out before dropping it off with someone. Thanks.

[anderbass]

Sounds like your VR has this problem with a simple solution:--> Johnk_10's SVT VR relay mod.

[brekfustuvluzer]

hey thanks anderbass. i have heard of this mod before but do you think this is consistent with the fact the my channel 2 stays functional?

[BassmanPaul]

I have a sense of deja vu! Try changing the preamp tubes one at a time between CH1 and CH2 to see if the problem follows a particular tube. If it does then replace that tube. If not it's tech time.

[derridiandrift]

I would suggest that you do JohnK's relay mod anyway. It's a simple mod, but the disassembly of the amp can be a bit of a chore, only because of its weight. If the mod doesn't solve your problem, it's good to have done that anyway. Then try Paul's tube swap idea. Like Paul said, if these two things don't solve the issue, I'd agree that it's time to see a tech.

[Tim1]

Ya, I did Johnk's mod on my VR a couple of weeks ago and it took me less than half an hour - I did not even need to take the amp right out of the body - I just stood it on its side and pulled it out just enough to get at the circuit board. Really easy. The standby light taking longer than normal to change was what prompted me to finally do the mod, and it definitely fixed it, but I doubt that this would be related to the other issue of channel one being quieter. However, nothing is impossible I suppose. As Derridiandrift says, try the mod first anyway then swap out the preamp valves - otherwise tech time.

[Tim1]

Funny, there has just been another post with an identical issue.

[derridiandrift]

If you haven't already done so, you might just want to replace all the 12AX7s in your pre-amp anyway if they're generic chinese tubes. It will improve the sound of that amp. The ones that come with that amp sound alright, but better quality 12AX7s will improve it, and it's quite possible you'll never have to replace them ever again unless you drop the amp.

[brekfustuvluzer]

thanks for all the replies! i think i will attempt the mod and test to see if it is a tube issue. if so, then ill just replace all the tubes anyway and use the old working ones for extras. if not, then ill hold off on the new tubes and take it to the shop. thanks again!