Friday, May 8, 2026

“Automony” - small signal preamplifier

 















Completed the cct. brds. thirty years ago and they have sat around until recently. There is no pcb but just a pad brd. There is no hookup wire on the brds. Each component is wired to the next directly with no other connection between. This I call component-2-component wiring, better the point-2-point wiring which uses hookup wire. To add to this there is six very expensive Jensen copper foil, paper and oil caps. Also two Solen caps plus a mix of carbon and metal film resistors.

Recently I discovered high voltage SMPS which I have successfully powered other preamps with. Here it also powers this preamp, the same “Universal” PS. The brds. plus a remote control Alps blue velvet pot fit snuggly into the Hammond wood cheek chassis. The preamp was designed for 12AX7s but here Im using LinLai 12AU7s. 

The finish colour is Ironstone and a heavy sculptured brass gold plated knob finishes the look. There is two inputs selected by a switch at the back. The sound is smooth and romantic. This maybe due to the both local and global negative feedback. This is old school design and has a lot to do with the smooth, creamy audio presentation. A fitting completion to what started thirty years go.