On a request from a friend I built this tube phono preamp. The schematic is one from an article on the Tubecad site. It employs a passive RIAA equalization cct. between two halves of a 12AX7s. In this case I used gold pin Golden Dragon tubes. The tube rings compliment the look and the sound.

The PS is separate and is powered by a 24VAC wall wart which is passed backwards through a 240V/24V step down tranni to produce 260VDC. Two stage HT filtering and DC on the heaters produces a quiet preamp.

Russian PIO military caps are used for the inter-stage coupling and Sprague "Orange drops" for the RIAA network. A switch allows 47K/100ohm MM/MC selection and both the PS and amp are constructed on veroboard. Ceramic sockets and silver solder compliment the build. The enclosures are Hammond anodized Al.

This phono preamp may well be the best phono stage I have built so far.

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