Where is best to sell old Brociner tube amp?

You need to find a website that is focused on selling audio gear that is typically not considered mainstream (Best Buy, Amazon, etc). Such a site may have listings for gear that is considered high end, rare, vintage, special purpose and anything similar. If I can think of one, I'll let you know.

Yeah. I'll help keep an eye out for that. What I suggest is once you find this site, if they happen to charge to list items for sale, just post in their forum looking for a recommendation of where to sell. You know, like a tacit ad without having to actually pay to list. Just mention the make and model # and wait for offers to flood your inbox.

How did Inheritedtubes post get past the moderators?

And surprise!...he's a new member, and it's his first post.