Jim Kelley Amplifiers

[2] The single-channel version of the amplifier employed modest gain in the preamp stages, Baxandall type bass and treble controls, a split load phase inverter, and four 6V6GT output tubes.

[5] Jim developed these high-power continuously variable L-pad attenuators as a means of controlling the overall volume of his amplifiers so that the output section could be overdriven at more modest sound pressure levels.

Further amplifier innovations were incorporated into the FACS (foot-activated channel switching) model, which built upon the single-channel design by including two similar switchable preamps and tone stacks, independent reverb level controls for each channel, and internal relay switching for the external power attenuator.

A rack-mounted, all-FET stereo guitar amplifier with analog delay reverb was developed but never brought to market.

[8] From 2012 until 2017 Suhr Guitars (JS Technologies) reissued the single-channel Reverb Model and Power Attenuator under a licensing agreement with Jim Kelley.

[9] In 2018 Jim began building a new single channel version of the Line Amp model in limited quantities from his own shop.

Among the unique feature of these amps are the dual concentric potentiometers, providing control of Gain, Treble, and Bass for each of the two channels.