slaveunit
New member
Posted this over at the Soldano forum but I thought Id throw it up here too.
I bought a used avenger 100. It arrived with a dead tube. Not knowing, I ran it for about 30 mins this way and it sounded good. Once I noticed it was dead by measuring I removed them all. They were Sovtek 5881wxt. I ordered another set. While I waited I put in some JJ 6l6gc ones. At that time the plate voltage was at 507. I set them to about 32ma. Used it for a while one day. Went to turn it on the next and 2 of the tubes blew...insanely loud pop and bright light in the tube. Next I took it to an amp tech to make sure no screen resistors or anything was damaged. Everything checked out fine. The plate voltage was at 507 at the tech's house as well. We figured it was a bad tube and maybe once that went it took out the one next to it.
Now the other day my Sovtek replacements arrive. Being really nervous about the last one dying a loud horrible death, I decide to first make sure each one is good with a tube tester, then put a probe on each one in the amp. When I do this the plate voltage is at about 525 now. Also one tube is much higher than the rest (14.7ma higher). I did move to tubes around and remeasured just to be sure its not a socket. My outlet voltage is at 118 but of course moves a tad all the time. The tubes are biased at about 10 ecept for the one which is at about 25. I havent even played the amp since the new tubes have been in. Ive only tested.
My concerns:
1) Should I be concerned with the plate voltage being about 20 volts higher now? Is this high for this amp?
2) I will be sending the tubes back. But they do have a bit of a staticy sound. Like when someone rubs a mic on their shirt or something. Could this be caused because of the tubes being so mismatched?
Thanks everyone for taking the time to read this.
I bought a used avenger 100. It arrived with a dead tube. Not knowing, I ran it for about 30 mins this way and it sounded good. Once I noticed it was dead by measuring I removed them all. They were Sovtek 5881wxt. I ordered another set. While I waited I put in some JJ 6l6gc ones. At that time the plate voltage was at 507. I set them to about 32ma. Used it for a while one day. Went to turn it on the next and 2 of the tubes blew...insanely loud pop and bright light in the tube. Next I took it to an amp tech to make sure no screen resistors or anything was damaged. Everything checked out fine. The plate voltage was at 507 at the tech's house as well. We figured it was a bad tube and maybe once that went it took out the one next to it.
Now the other day my Sovtek replacements arrive. Being really nervous about the last one dying a loud horrible death, I decide to first make sure each one is good with a tube tester, then put a probe on each one in the amp. When I do this the plate voltage is at about 525 now. Also one tube is much higher than the rest (14.7ma higher). I did move to tubes around and remeasured just to be sure its not a socket. My outlet voltage is at 118 but of course moves a tad all the time. The tubes are biased at about 10 ecept for the one which is at about 25. I havent even played the amp since the new tubes have been in. Ive only tested.
My concerns:
1) Should I be concerned with the plate voltage being about 20 volts higher now? Is this high for this amp?
2) I will be sending the tubes back. But they do have a bit of a staticy sound. Like when someone rubs a mic on their shirt or something. Could this be caused because of the tubes being so mismatched?
Thanks everyone for taking the time to read this.
