Build a MOSFET Citation 12 — Nelson Pass / 1981

Audio Amateur has published a number of projects modifying popular kits, usually Dynaco's. Obviously it is much less expensive to use the chassis and power supply, pots, connectors, switches, PC boards, and heat sinks that can be had for the price of a kit than to buy the components individually or have them made. Creating a one-off copy commercially typically costs as much as making 10 copies of the same item, because the dominant costs are design and set-up time which do not increase with quantity. Small wonder then that most technicians and designers who write for this and similar… More...

Pearl 2 — Wayne Colburn / 2010

Here is the long awaited sequel to the Pearl phono stage, named after my maternal Grandmother who was good with a sling shot , played piano and organ and occasionally listened to my early Hi-fi efforts if the smoke wasn't too bad. Pearl II addresses the major request received over the years - more gain for moving coil cartridges. Phono stage design is difficult to do well. Everything matters. Any low level phenomenon occurring in the parts of a phono stage shows up greatly amplified at the loudspeaker. This phono stage has about 55 dB gain at 1 Khz, and… More...