I bought a very used MM75 a while ago which was disassembled and in a box but was promised to work properly if assembled. Amazingly, it does work and quite well but I'm not sure if the caps are original or if they have been replaced. Can anyone tell by looking at them? Here's some shots of the under-chassis.
As usual, I couldn't upload photos directly to the forum so I've put the here:
http://www.davidg-photo.com/mm75/
Many thanks,
David Goldberg
My MM had the original silver Sprague caps also.
The current production Sprague caps I have bought are blue.
https://www.cedist.com/products/C-SA
Look in the Dog House
Inspect the big hi voltage caps under the "dog house" too. The ones in your pics are the low voltage supply filter caps and various inter-stage coupling caps. Looks nice and clean BTW. Nice score. -mgriffin
Everything I saw look
Everything I saw look original but as stated above, those don't really matter much except for tone. You need to check the filter caps under the cover to see if it's had supply caps changed. Mike.
Those Caps are Original
The blue and silver caps are originals. You will find a code on them indicating when they were made, probably late '80 or early '81.
And while the big power filter caps in the doghouse are probably the most important to replace after 35 years, the amp overall will serve you better with all the old caps (blue and silver) replaced. This comes from my own experience, and from those who were there when these amps were built.