Markbass Big Bang

[lowell]

Has no power. AC is good, but no DC in SMPS. I emailed them but haven't heard back. Looks like they're very secretive with their schematics. Anyone able to email one to me?

Thanks!

[Jazz P Bass]

Probably not much help but here is a list of Mark Bass non warranty repair stations.

Maybe one of these chaps would cough up the paper.

Authorized NON.doc

[lowell]

Thanks! I got a response, they don't share em. I responded asking how to be an authorized service center. No reply yet.
He did however send a quote of $170 for a new power/amp module. So I'm going that route as the owner wants to fix it.

Thanks for the list!

[lowell]

Owner ended up goin for the new module. Got it ordered today.

[Jazz P Bass]

And the failed amp goes in the 'parts tub'.

[lowell]

Yep!

[Jazz P Bass]

Mine is getting awfully full.

[lowell]

Fixed it. Thanks to this thread!! Finally got useful reading from my Blue ESR meter. First time I've been able to measure high ESR on a cap. Nice.

http://music-electronics-forum.com/t10881/

Same cap went bad in mine too. Replaced with 400v 1uf cap. Works great. Awesome to have a schematic too for the future.

[lowell]

Here's a pic of the backside of the new board with parts numbers. The original board wasn't numbered. In case anyone can benefit.