After spending many years to write an encyclopedic tome on audio power amplifier design, Bob Cordell decided to turn his considerable talent to the design of a phono preamplifier. Strictly solid state, his design using the best device for each position: jFETs for the input stages, BJTs for current sources and amplifying stages, and operational amplifiers for the output stages. Here, Bob proposes a different approach to achieve the 75uS hf RIAA roll-off that eliminates the cartridge electrical resonance and extends the electrical response well into the ultrasonic range. The design is single ended in and balanced out, and uses fully separate preamp channels for MM and MC cartridges.
VinylTrak – A full-featured MM/MC phono preamp