Does anyone know the relationship between the Eighty-Five, the Studio 85 and the Deluxe 85? I just picked up an Eighty-Five and it has the year 1987 on the circuit board. From reviews on Harmony Central, the others appear to be from the same time although the Studio appears to have a 10" speaker rather than a 12". I need to order a schematic and since I don't see one listed for the Eighty-Five, I am trying to determine if the Studio or Deluxe would be similar.