Found some info on Sound Barrier amplifiers, but couldn't find anything on that particular model. It's possible it wasn't sold in North America. The GA Series of amps that were sold in 1994 were the GA-100 (50x2 $100), GA-240 (60x4 $150), GA-200 (100x2 $190), GA-340 (75x4 $278), and GA-400 (200x2 $300). The only description is that they feature MOSFET circuitry.
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