Looks like it’s a mid to late 90’d amp. The earliest the Memphis website goes back is 1999, so the amp was likely around / before that time. Not a prototype, just older so less info available.
Screenshot below of internet archive of the Memphis webpage back then.
Lastly, there is a youtube video of one of these amps, and on the handheld amp dyno, it did 62w x4 @ 4-ohm, 92w x4 @ 2-ohm, 150w x2 bridged @ 4-ohm. I don’t know how accurate that is, but I likely it is in the ballpark. There are also comments in that video stating it's time period and some history on it, the board in this Memphis amp was a carry over from the Fultron brand that became Memphis,
which would date this amp to about 1998.
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