The Peavey Multifex appears to hail from such a period. Boasting four independent stereo digital multi-effects processors in a 1U package, in 1990. I had a quick hunt for reviews, a search which ended in nothing (once I decided to ignore the nefarious dead-end search engine "sell him something anyway" results).
Rear panel, I imagine this can be somewhat congested once everything is wired up. The output level controls are wholly in set & forget territory.
Gutshot! Now we're getting somewhere.
Analog signal section, largely populated with socketed 4558. The tinkerer in me loves socketed ICs, and having a quartet of identical circuits is inviting for direct A/B comparisons of chip swaps.
The digital section for one bank. BB PCM55HP doing DAC duty, I'm still pondering what cuts the analog into digital.
Double decker digital.
I'll have to find a 1 amp 16-16.5 VAC power supply to fire this up, but before I get that far, the backup battery eruption needs to be mitigated. So... jury will remain out whether this is a suitably pretty rare bird or a suitably grimy hunk of junk. Either way, I expect this will find a place in a rack.