Loud popping when turning roadster on

[iceman]

Went to play my Roadster tonight. When I flip it from standby to on there is an immediate cracking and popping that is very loud (I turned it back to stand by right away). All 4 heaters in the power tubes look normal, doesn't matter if I have it set to 50w/100w or rectifier/diode. Which tubes should I start pulling? Or should I just take it into a tech?

I'm kinda freaked something happened with my power at my house. My fairly new computer died yesterday... The roadster is on a furman mx8 power strip. The computer was on a cheap power strip. The triaxis on the same furman strip seems ok so far, I'm afraid its next though..

Thanks

 

[b0nkersx]

Does it happen every time? On more than one outlet? See if you can try another outlet at a buddies house or something, just to confirm it's the power. I see no reason to take it to a tech yet. It could have just been a bit of slight static discharge.

 

[iceman]

I tried it on another outlet. This time I didn't wait the 30 sec or so to turn from standby to on. It was quiet and then got louder and louder so maybe its just the power tubes. I did a swap of them (xyyx to yxxy) the other day just because I play mostly on spongy. So maybe I cycled in a bad one. Which tubes are for 50w? x of yxxy or y?

 

[b0nkersx]

I tried it on another outlet. This time I didn't wait the 30 sec or so to turn from standby to on. It was quiet and then got louder and louder so maybe its just the power tubes. I did a swap of them (xyyx to yxxy) the other day just because I play mostly on spongy. So maybe I cycled in a bad one. Which tubes are for 50w? x of yxxy or y?

I believe it is the "y" tubes, but I'm not certain. Someone on here might know for sure. It might be in the manual, too. It might be a preamp tube if it's a strange crackling issue.

What I do if I don't have any extra preamp tubes is hard-bypass the loop on the back and switch out the effects loop 12ax7 with all of the other 12ax7s in the amp one at a time and see if that solves any issues. You could try this.

 

[iceman]

Some more info... all volume/master are 0 when this happens. I'll just try swapping the power tubes, inner from the outer I guess.

 

[iceman]

Turns out to be the v6 tube. That is the 5th preamp tube I've replaced in less than a year on this amp. Either I have really bad luck, mesa tubes really suck or something is up with my amp. I just replaced the v5 tube two weeks ago (2nd time for that position). Why does it always have to be the last tube you check.