those are effects units made by Electrix, now discontinued. they sound REALLY good though... and were REALLY cheap ($300-400 new.... GC sold them at one time for $100 each. i bought their entire stock and sold each one for $200 on ebay and made THOUSANDS of dollars.) but even at $300-400 they were still a great deal. the red one is a vocoder, the green a filter, the blue a time-sync'd effects, and the smaller yellow an absolute cut EQ used for remixing, and the small green another filter.
if you look at the pictures of composition studios in Keyboard and similar mags, you can see many big name producers and composers with these things in their racks.......... love 'em. they look like cheap plastic in the pictures, but they are actually in die cast metal cases that are 1/4" thick!
if you can find them for $100-200...i say buy it!--they're so fun!
