MM HD 130 owners have you tried the EH 6ca7 big bottle tubes?
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A few months ago I was trying to help another TBer decide on which tubes for his HD130. After removing one of the current tubes (EH EL34 EH) from my amp to check it for him, I somehow replaced it wrong and broke the plastic center key.
So, I need a new matched quad to get it back up and running and was wondering if anyone is currently using the EH 6CA7 EH big bottles? I will say I was very happy with the EL34's and they were still going strong until my screwup. As it seems there is only about a $20 difference in prices would you elect to go for a new set of 6CA7's or just get another set of EL34's.
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A world without music would be wrong!
i haven't run them in a MM amp, but i have used the the big bottle 6CA7 in a few amps. i found them to have a fuller/rounder low end than standard the standard skinny shaped EL34's.
You don't need to replace the tubes. Having a broken locating pin won't damage anything. Just carefully insert the tube that worked and you were happy with.
John
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JTE Spelling, grammar, and punctuation do matter, despite the threats of death by grease fire!
"Without space, music is just noise piling up on itself." TRK
The good news, the amp fired up, all 4 tubes lit up, but now it sound like it has built in fuzz. Not sure if I replaced the tubes exactly in the same order. Could this be the problem? I'm not sure how many possibilities there are but I'm willing to switch if that will bring back the good clean tone it had.
I'm thinking that back when I replaced the tube wrong and turned it on, it immediately blew the fuse. Maybe I fried something then?
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A world without music would be wrong!
Is there a larger gap between 2 of the pins or is it possible you rotated it and plugged the wrong pins in the wrong holes with out the keyed center piece there?
If they're a matched set it won't matter what order you put them in unless it has a hum balance adjustment like fenders and it was adjusted to balance out a set of tubes that wasn't so closely matched.
I'm no tech but I can't imagine that being ok for the tube at least. Were it me I'd have it looked at by a pro to make sure other parts inside are ok, hopefully the fused stopped any major damage. Techs who've been in business for a while usually lots of boxes and bins of oddball parts around. Perhaps he has a tube or 2 around that match close to yours, who knows. It sucks when something little like that sets off bigger problems.
After carefully removing the chasis, I have found the results of putting a tube in rotated. See source of magic smoke
At the end of the large cap the power arched to the chasis.
Now I need to find someone competent (long story) that know Music Man amps. Somewhere between Modesto/Reno/sacto, I don't want to ship this for repair.
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A world without music would be wrong!
A few months ago I was trying to help another TBer decide on which tubes for his HD130. After removing one of the current tubes (EH EL34 EH) from my amp to check it for him, I somehow replaced it wrong and broke the plastic center key.
Just glue the plastic key back on. Failing that you can get a replacement that slips over the tube pins from Antique Electronics
See source of magic smoke 
