in the early '70's, ibanez made a howard roberts model archtop gtr(copy of a gibson). it had a passive midrange control that, apparently, used some kind of inductance coil. does anyone know of this or of a site or community of gtr/electronic heads that might have a schematic of this circuit? also, do you know where i might get a coil that would work in that circuit?
thanks
jack

Try Torres Engineering or Griblin Engineering. One or both of them may have a passive midrange control. I don't have their web addresses handy.