My Mark IV Went Kaput!

[sixstringmonk]

My MKIV died last night. I had been playing it on tweed power for about an hour. I flicked it up to full power without letting it shut down and the power went out on the amp. No lights no nothing. There wasn't any smoke, it just simply and immediately lost power. I checked the fuse but it looks ok.

Any ideas?

 

[Shep]

Check your fuse with a meter!

 

[JPM90th]

Interesting. Here's a question, Is it bad for the amp to just flick from Tweed to Full Power and vise versa without letting the amp shut down for a bit?

 

[Boogiebabies]

I have always used standby first. Shocking the tubes with an extra 100 or so volts is not something they like. Like Shep said, try the fuse. It may have blown the varistor as well.

 

[JOEY B.]

When I switch from Simul to Class-A or vice versa, I do not use the standby. I also do NOT switch this in a rapid-fire manner. As no one in their right mind would rapid-fire their standby switch :roll: . When I had a MkIV, the standby was activated when the amp was switched into or out of Tweed or Triode modes. Severe duty tests are a part of the manufacturing (warranty) process. It doesn't mean that it's the smart thing to do :wink:

 

[phyrexia]

i've done that rabies. didn't do anything.

 

[JOEY B.]

i've done that rabies. didn't do anything.

Victor, get your Mark III nice and hot, then try a rapid fire on the standby switch. Let me know how long the power tubes last after that kind of abuse. Care to roll the dice with your own amp? :wink: :lol: There is nothing quite like seeing smoke roll out of your favorite amp. I've seen it twice. :evil:

 

[sixstringmonk]

Check your fuse with a meter!

It WAS the fuse. I guess I had never really seen a slow-blow fuse before. They don't go poof the same way an old school fuse does. Now I can see there is a break in the wire.

 

[ANIMATED SUSPENSION]

So why would the fuse blow ? Going from tweed to full power can't be as bad as going from standby to full power surely ?? Are the tubes ok and does it work now !?!?

 

[sixstringmonk]

So why would the fuse blow ? Going from tweed to full power can't be as bad as going from standby to full power surely ?? Are the tubes ok and does it work now !?!?

I don't know 100% why it blew but since it blew while I flipped the power switch from tweed to full I'm going to blame that unless I start blowing fuses left and right. The tubes seem ok. I played through it for about 2 hours last night. Also, FWIW, I'm running the amp off of a Monster power conditioner.

I hope it was a fluke. I don't want my amp to die :shock:

 

[straitouttahell]

I don't know 100% why it blew but since it blew while I flipped the power switch from tweed to full I'm going to blame that unless I start blowing fuses left and right.

I blew a power tube exactly this way. For some reason, switching from tweed to full power all of a sudden is something the amp doesn't like.

 

[JOEY B.]

I blew a power tube exactly this way. For some reason, switching from tweed to full power all of a sudden is something the amp doesn't like.

:wink: :wink: