2002
AL#69 p.22   BRB6 p.296            read this article
Joseph Ennis                                                                                           

▪ Build an amp that matches the resonance of your acoustic instrument. Build it into the instrument if you like. Ennis offers some math, some circuitry, and some advice to beginners who want the most portable amps for their instruments. With 9 photos and a circuit diagram.