thereīs an quite old Akai device called PEQ6. It has 6 Channels with 7 fixed frequencies to be tweaked per channel and 32 program storage, Midi In/Out/Through, 19" 1HE. Itīs very easy to operate and can sometimes be found for about 50-80 US $ on e-bay. I sold mine 2 years ago, because it was just standing around. But before that I had used it for at least 15 years without any failure. The sound quality is not High-End but sufficient for live gigs (i.m.o.).
Hereīs a link to an old e-bay auction with picture and a bit of information:
Greetings from Spain
indiependence music: www.indiependencemusic.net/artistPage.php?artistId=2742