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View Full Version : Fried a 67 Vibro Champ



6STRINGS 9LIVES
January 22nd, 2007, 07:35 PM
Man am i pissed , i recieved some nos 6v6gt tubes today.. changed out the old one and installed the nos general electric 6v6gt , plugged her back in switched it on and let it warm up .. plugged in a strat set it on 3 and man it was just the creamiest warmth , beautiful .. dimed it and let it rip .. had some real good grind then it all turned to crap it just died and then i smelled the dreaded electrical burning stink all in about the space of 10 seconds ...i think the trannie is cooked , total drag the amp was all original and a favourite .. gotta pull it appart and see what cooked in there ... anybody ever have anything similar happen , in all my years this is a 1st for me , now i got da blues ...6s9l

M29
January 22nd, 2007, 07:55 PM
Hello 6s9l,

I know this might sound trite but did you try another speaker? We used to jam in my friends basement back in 1970/71 and our guitar player had a Sunn 1000 amp with two JBL fifteens and a horn in one cab. We were playing along with my friends Sunn set at 10, which we allways played at and the thing quit. We figured the speakers were fried and proceded to remove the rear panel on the cabinet. You know how many screws there are on those big old cabinets and it took us a quite a while. When we finally did get into the speakers, they were fried and they were still so hot that we could not put our hands on the magnets. I did not think a speaker got that hot but those babies were (very) hot even after we took forever to get the back off. Just a thought...

Another thought... If this was not your amp originally you may want to check the fuse rating that is in the amp,(you may have already done this). Sometimes people over fuse things and we don't notice them if we buy them used.

I am sorry to hear this that is a nice amplifier.

M29

6STRINGS 9LIVES
January 22nd, 2007, 08:12 PM
Good suggestions M29 , just pulled the chassis and the output transformer is sooty and stinks .. gotta call in to my amp tech .. I cant understand why a tube would cause the ot to fry though .. I changed tubes because the original ge 6v6 was soundinga little weak lately ..cant see how that woukld lead to a trannie failure though .. gonna put the original tube back in while the chassis is on the bench and see what happens ..

tot_Ou_tard
January 22nd, 2007, 09:27 PM
YOW! that hurts from here...good luck 6S9L!!!

Spudman
January 22nd, 2007, 10:43 PM
Karma! Can't escape it. Sounds like you are caught up now.

Your bias may have been way off for your new tubes. Did you check it after installation?

Robert
January 23rd, 2007, 12:06 AM
Oh no, what a tragedy. I mourn with you, my friend.

sunvalleylaw
January 23rd, 2007, 12:10 AM
Oh no, what a tragedy. I mourn with you, my friend.


Echo that. Hope it fixes up alright! :(

oldguy
January 23rd, 2007, 07:50 AM
Sorry to hear that, 6S9L. The amp can be fixed, I guess the "all original" thing is what's depressing, huh?

duhvoodooman
January 23rd, 2007, 08:13 AM
Wow, bummer! I'm sure it can be fixed, but that's gotta be a traumatic experience. I feel for ya, bro'! :(

Any chance that you could have gotten a bad tube or (hope not!) they weren't what they were represented to be? I read horror stories all the time about the fraudulent practices and chicanery that goes on in the NOS tube market....

tot_Ou_tard
January 23rd, 2007, 08:24 AM
Karma! Can't escape it. Sounds like you are caught up now.

Your bias may have been way off for your new tubes. Did you check it after installation?
Bias is really that important? It sounds like such a little thing. I never even understood what it meant.


My bias has been way off for a long time too. Does that mean that I'm gonna spontaneously combust? :D

6STRINGS 9LIVES
January 23rd, 2007, 08:50 AM
Hey ...The champ/vibro champ are single ended (1 power tube) so they are self biasing(cathode biased) no need to wory about biasing a new power tube ..thats why i was so surprised it should have been fine , dropped the amp off at my amp techs shop this morning and he did a quick look see, he says that the nos ge 6v6gt that i recieved yesterday was toast and apparently while looking brand new ( even in the original box ) it wasn't , and as soon as I pushed the amp it went south.. the good news is that the output transformer seems ok , and the soot i noticed may actually be decades old .. anyway he's going to give her the once over today and make certain its ship shape ... I will be calling the Tube supplier this morning as well if things dont work out there I'll post the name of the business with a huge warning to stay away .... anyway guys thanks ... I felt the love lol .
Tot...according to the good folks at KCA NOS Tubes & Amp Repair "Setting the bias is like adjusting the idle of your car. If not set properly, the performance (tone) of your amp will suffer. If the bias is set too high for your new power tubes, you can destroy them in a matter of minutes. You can also damage your amp. If the bias is set too low, the amp will sound weak, thin and anemic. " my guy says the plate voltage in my champ checked out ok so it most likely was a poor tube ... we'll see .... 6S9L

Tone2TheBone
January 23rd, 2007, 09:37 AM
6 - Does this mean that NOS tubes aren't tested at all before shipping to customers?

6STRINGS 9LIVES
January 23rd, 2007, 11:19 AM
Tone .. most if not all nos tube sellers state that they put their tubes on a tube tester and they report the results .. i have bought nos tubes before without incident , but it was the first time from this seller , it was an on line transaction .... so who knows it might have been an honest mistake and the seller will make things right .. I will post how this gets resolved .. but i do think that most sellers are honest and trustworthy .

Tone2TheBone
January 23rd, 2007, 11:31 AM
Maybe it was just a fluke. That sucks that it happened on the Vibro Champ though. :(

warren0728
January 23rd, 2007, 12:29 PM
hey the good new it it looks like the amp is ok!!

i am really happy with jj tubes and bob at eurotubes can put together a custom set based on the sound you are looking for.

I know they aren't NOS but they are really good tubes at very reasonable prices....

ww

6STRINGS 9LIVES
January 24th, 2007, 11:36 AM
Picked her up from the shop today ... it lives and is fine ... tube will be replaced by the seller .. cheers ... all is well that ends well .

duhvoodooman
January 24th, 2007, 11:46 AM
WHEW!!! That's great to hear, 6! :DR

warren0728
January 24th, 2007, 11:49 AM
it lives and is fine
excellent... :DR

ww

Tone2TheBone
January 24th, 2007, 11:51 AM
Awesome news 6! Now post some sound clips of that baby. :)

sunvalleylaw
January 24th, 2007, 01:49 PM
Great. great news!! Glad to hear it.

tot_Ou_tard
January 24th, 2007, 06:27 PM
Hot Damn!!! Be careful, she only has 8 lives left.

Mark
January 24th, 2007, 07:26 PM
Glad to hear its up and running. Man Im getting addicted to these old fenders!