LSS Head EFFECTS LOOP SHORT OR BAD CAPACITOR ??????

[hippdogs]

I've got a LSS head. After amp is warm (10 min. of playing) hard by-pass seems to be clean and clear, as you would expect. When effects loop is on, with nothing inserted into the jacks, I start getting break-up, crackling and then it sounds like it is shorting-out......varies in volume, including going completely silent, but when I strum the strings hard, it will pop back on for a bit, and then crackle and fade again. Changing the switching wattage does nothing to change the shorting. Changing between channel one and two, makes no difference...still shorts. I've changed the V3 tube which is the effects loop tube, no effect. also: when I turn the amp off, with the effects loop switched on (nothing connected), it makes a lot of rumbling noise as it powers down. Maybe a bad capacitor?????? SUGGESTIONS? :shock:

 

[ziehmrd]

Could be dirty contacts on the effects loop jacks. I and others here have had this problem. Some folks use contact cleaner or open the amp and adjust the contacts to make them tighter. In my case, just taking a patch cable and inserting/removing it from the loop jacks several times took care of the problem.

 

[hippdogs]

Even with nothing inserted into the effects loop?

 

[MrMarkIII]

Many effects loop jacks are shorting jacks. IOW, there's a contact which is normally closed when the jack is not used, i.e., no plug inserted.
This way, when there's nothing plugged into the loop, the send and return jacks are effectively connected to each other.
Don't know for sure if this is the LSS problem, but other Boogies have these jacks.

 

[hippdogs]

Cleaning the effects jacks and ribbon pins seems to have successfully solved the problem.....thanks for all the information.