Cheers!~
I, too have been on a quest to obtain a schematic for a dbx 20/20. I was informed by a tech at Harman International last summer that the dbx 20/20 schematic went up in flames when the dbx company in Connecticut burned down (which would be strange considering part of having a patent on an invention also includes submitting a schematic). I also heard a "disgruntled engineer was had stolen and/or was hiding the schematic until he was paid for his services and contributions." If you ever find anything out please let me know and I will do the same. Best regards!~
sbs38