NAD THX 2400 Amp

real world price for your amp is $200-250. you should have no problem selling it in that range.

I guess the original 2400 is from the late 80’s, but many are suspicious of an amp over 20 years old. But some prefer older stuff. It should sell

Thank you for your responses…it’s actually 24 years old (still pretty old) though when I fired it up, it sounded fantastic.  I’ll keep my fingers crossed. 

and some believe that hardly used amps actually age faster...

a 35 year old amp can still play well, but can have degraded internal parts (many of which can be hard to replace), so many are hesitant to buy...