Be sure to add me to your favorites list Original Yamaha Q2015A Graphic Equalizer Rack Mounted EQ Service Manual, Schematics, Etc. Book Great, original Yamaha service manual for the Yamaha Q2015 A Graphic Equalizer rack EQ unit. This is a full service manual, with specs, block diagrams, panel layout, circuit board layout, several schematic diagrams, full parts list, overall circuit diagram and more. This booklet is in very good condition, with some minor storage wear, and it would be very helpful to work on and repair your Q2031B. Original Yamaha document, printed in Japan, from 1996. This is a manual or document, this is NOT a piece of equipment or instrument. If you have any questions, I'm always happy to answer them. Thanks for looking, Check out my Store!