New Balancer PCB and Kit

Cathode-Coupled Amplifier

Cathode-Coupled Amplifier
This clever cathode-coupled-amplifier variation greatly enhances the circuit's PSRR and lowers its output impedance. The circuit consists of a modified cathode-coupled input stage that uses an extra cathode resistor to equalize the current drawn by both triodes, followed by a two-resistor voltage divider, which cascades into a cathode follower. The result of both these additions is that all the triode cathodes rest near ground level at idle and the power-supply noise falls out of the equation and out of the output.

Cathode-Coupled Amplifier PCB
Each PCB holds two cathode-coupled line-stage amplifiers; thus, one board is all that is needed for stereo unbalanced use (or one board for one channel of balanced amplification). The Cathode-Coupled PCB makes building a standard-setting line stage amplifier a breeze. This assembled board with a chassis, volume control, selector switch, power transformer, and a fistful of RCA jacks is all that is needed.