Ovation OP-X Pre-Amp Schematic

Professional multi-board preamp schematic for the Ovation OP-X onboard guitar preamp system. Comprises four circuit boards: Input Board (40-601BH) with JFET buffer, state variable notch filter, and volume control; Slider Board (40-602BH with tuner, 40-603BH with graphic EQ) featuring slider-based bass/treble/600Hz/6KHz EQ controls, graphic EQ bypass, notch bypass, and chromatic tuner with calibrate function; Output Board (40-604BH) with balanced XLR output, 1/4-inch output, and 11V zener protection. Also includes battery box assembly diagram. Drawing Rev 2, dated 8/17/94, drawn by N.M. and b.h. for Ovation Instruments. Most advanced Ovation preamp design with phantom power support and professional output options.