The Black Panel Fender Princeton Amp ("non-Reverb") is a highly sought-after vintage guitar combo, perfect for small clubs and recording studios. With built-in tremolo/vibrato circuit and 12 watts pushing a 10" speaker, the Princeton was something of a middle-ground between the smaller Vibro Champ and the bigger Deluxe Amp. The earliest Black Panel Princetons have a couple anomalies -- the "tuxedo" cosmetics from using leftover Brownface parts and a simpler Tone circuit. By the fall of '64, the more common Black Panel-era cosmetics (numbers on the knobs, not the faceplate) came about and the circuit was revised to have separate controls for Bass and Treble.