Announcement

Collapse
No announcement yet.

Powering up unused SS amps periodically?

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

  • #16
    A recent case history for illustration. A customer put away his Gallien Krueger 200MB bass combo some 20 years ago when it failed to light up one day. When he finally brought it in a couple days ago, I found the 15V supplies weren't working at all, due to failure of their 220 uF filter caps. After replacing those, tried firing up the amp and roasted a couple of small resistors being used as fuses in the low voltage supply. More of those 220 uF caps in other locations powered by those 15V supplies. After replacing half a dozen of those 220uF caps, the amp works as well as it ever did.

    It was probably the failure of one of those 220 uF's that put this GK on the junkpile 20 years ago. Lack of being charged over the course of 2 decades damaged the others.

    Possibly this is a good quality amp for the most part, but the acoustic hum from its power transformer makes it annoying to use with any quiet live act, and for recording there's obviously no point in mic'ing up the speaker with all that racket going on. Strictly for loud rock. As loud as you can get with a dinky 1x12 combo...
    This isn't the future I signed up for.

    Comment


    • #17
      That transformer might deserve some vacuum varnish impregnation.
      Juan Manuel Fahey

      Comment

      Working...
      X