My Mark V head just blew a rectifier tube

[Oldschool]

So I´ve been using my Mark V head for a year now, gigging almost every weekend, so it´s seen some action and traveled quite a bit.

Last Friday, when turning it on during a soundcheck, the amp turned on but no sound. After some cable checking, I turned it off and on again, and the fuse blew. This sounded exactly like a problem I had with my LoneStarSpecial when using the 5 or 15watts - blown rectifier tube.

I didn´t have spare fuses, so I borrowed a JCM800 head and got through the gig, and when inspecting my Mark V yesterday, I found that the rectifier tube was indeed the culprit.

Contrary to what I´ve read here on the forum, the amp works with a blown rectifier tube, as long as you don´t have it switched on.

So I have two questions:

1) Is the rectifier tube problematic (have people been having problems with blown rec tubes)?

2) Are there better replacement rectifier tubes than the MESA 5U4GB?

 

[dmcguitar]

mine came with a noisy recto tube. when turned on it sounded like i as shaking a lightbulb next to my ear. annoying but not through the speakers, but i didnt want to chance it going bad, so they sent me a new one.

 

[Red Barchetta]

I just had my retcto tube short out at my gig Saturday night. I had to finish the gig by borrowing an old Johnson digital amp from the bass player (not that great) and stuck a TS-9 in front of it. It got me thru the gig, but I had to listen all night about how I was "playing with the bass player's Johnson". Geez.

I'm going to pick up some new fuses and a recto tube today, and used this as a good excuse to get a full retube kit from Eurotubes. I loved their retube on my old Roadking 1.

As the manual says: "It's not a question of IF a tube will fail, it's WHEN."

RB

 

[Don]

I think you can get a NOS 5U4GB for about $40.

 

[primal]

... but I had to listen all night about how I was "playing with the bass player's Johnson". Geez....

I busted out laughing so loud at that my wife asked me from the other side of the house what I was laughing at.

 

[domct203]

I think you can get a NOS 5U4GB for about $40.

You can find better deals than that if you shop around. I picked up a pair of excellent condition vintage Tung-Sol 5U4GB's for $24.00 + $5.00 shipping (in my Roadster), an NOS Raytheon 5U4GB for $10.00 + $6.00 shipping (in my MKV) and a pair of Sylvania 5U4GB's for $19.00 + $6.00 shipping for backups.

Dom

 

[boogieman60]

I broke my rec. tube at a gig trying to get my footswitch out of the pouch in the back of the combo..(took the pouch out after that put it and the F.S. in my gig bag) The amp worked without the rec tube..but everything was out of balance. I think it supplies voltage to the power tubes in some way. any comments? Any ways I couldn't use the amp that nite went to a back up. So as far as I am concerned the amp dosn't work without the rec tube.. on or off.

 

[rabies]

we took the chassis out of a mark V head and it has way too many tubes and way too complicated of a design (what's that extra high 12AX7 shield in V1?). i would never buy one of those amps after that experience. just such a pain to mount and dismount the chassis with two guys.

 

[Hendog]

I just had my retcto tube short out at my gig Saturday night. I had to finish the gig by borrowing an old Johnson digital amp from the bass player (not that great) and stuck a TS-9 in front of it. It got me thru the gig, but I had to listen all night about how I was "playing with the bass player's Johnson". Geez.

I'm going to pick up some new fuses and a recto tube today, and used this as a good excuse to get a full retube kit from Eurotubes. I loved their retube on my old Roadking 1.

As the manual says: "It's not a question of IF a tube will fail, it's WHEN."

RB

hahaha, it sounds like something my bass player and I would say to my drummer repeatedly. And it would never get old to us and he would think we were being idiots.

 

[Red Barchetta]

Went ahead and did the full retube with Eurotubes. Amp sounds great. I haven't played it at stage volume yet, that'll come this weekend, but the JJ tubes from Eurotubes are chock full 'o awesome.

RB