Monday, November 12, 2012

4S Universal valve preamp in a Tea box (4SUTea)

All housed in a Twinnings timber Tea Box: Bitumanised Al foil controls enclosure resonance and Russian paper in oil caps link the modulated HT to the real world. Silver solder is used throughout. Heavy duty high grade gold plated RCAs grace the back and all is powered by a 24V 1A plug pack. There are two switchable inputs, Alps blue velvet pot and black chromed solid brass knob.

Power supply and amp reside on a single piece of vero (strip) board. No PCB or shielded wire is used. Any 12A?? tube can be inserted with no components changes. Sound is big, bold and fast with a Mullard 12AX7 in place.