Airbrake shorting out?

[Matt J]

I've been writing about this in another post but I thought this deserved its own topic.

I have been finishing up my Express build and kept incurring a stacity/overloaded sound whenever I really dug into the amp and hit a hard chord. It was as if something was shorting out and sounded like what happens when you have a bad guitar cable that is cutting in and out.
After doing a lot of diagnostic work, I think it is not something inside the amp but a problem with the Dr. Z Aibrake I am using. I tried the amp out with another attenuator and did not encounter any problems. I picked the Airbrake up on Ebay a few months ago with the intention of using it when I finished my express build.

Has anyone else who own an Airbrake experienced a problem similar to this? Should I consider completely gutting it and rebuilding it from scratch with the info available here on the board? I took some internal photos of it to see if anybody can spot any obvious problems?

Thanks!
- Matt J.

[Matt J]

more photos

[funkmeblue]

is the airbrake sitting on the speaker cabinet? I would make sure the screws are tite and making good contact on the adjustable tabs on the adjustable resistor

[phsyconoodler]

a loose or cold solder joint can cause the symptoms you are describing.Clean the contacts for sure.There is not much inside that attenuator that can cause issues.Loose,dirty of cold solder joints are the only things that come to mind.

[HeeBGB]

Before you do anything....have you checked both speaker cables? And the jacks they plug into? I know it sounds dumb but I always get bitten when I skip the stupid stuff. Rule out all the dumb stuff then look for more complex problems.

[selloutrr]

While you are at it, I'd check the resistors under heat.
Since you purchased the unit used, who knows if the previous owner(s) used it with in it's wattage guide lines.