Just reading the Recording Hack dude has a Symetrix 302 and it gets some good tone praise several times. I sold mine because they were so clean. The 528E were weird too selling for $900 on B&H but all over used for $150 or sometimes less. The few I tried were built like tanks and really quiet and great gate/expanders. I got the impression large venues bought them or something? Good gain, good paint and metal etc… solid…just no transformer/tube/flavors.
Industrial preamps?