2. amps-preamps
  3. 191188-135431

What is causing false tube faults in VTL MB450 Series III?

I’m having trouble with one mono vtl amp which frequently signals a tube fault (red faults,green fault) requiring 2-4 reboots. The tubes were purchased  recently through VTL. The tube(s) responsible for the warning alert changes. After repeated restarts the amp performs as expected.The second amp with new tubes as well does not have this problem. Any thoughts? Thank you

michaeldouimette
roxy54's avatar
roxy54
7,977 posts
 

@michaeldouimette 

Seems obvious, but isn't VTL helping you troubleshoot this?

carlsbad2's avatar
carlsbad2
1,602 posts
 

Guys, as the OP has already figured out, It appears to be the VTL tube monitoring/troubleshooting cirecuit that is at fault, giving false indications of a bad tube.  

I don't know how to troubleshoot this.

Jerry

langla4
37 posts
 

If your experience with VTL service is anything like mine, good luck.  They could not have been less responsive and Bea said their service is backed up 6 months.  I live around LA so I took mine to George Meyer.  Two week and it was fine.

hiend2's avatar
hiend2
418 posts
 

Jeez

George Meyer is great Place.

Just brought my monos in for a alignment ect.

They have the "Big" stuff there Saw the Big brother to your 450's there Woltan

and 10 tons more.

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