Tube Cad Journal Aikido 9-pin

About the Tube Cad Journal Aikido 9-pin

The GlassWare Audio Design Tube CAD Journal Aikido 9-pin is a DIY printed-circuit-board platform for building a stereo Aikido vacuum-tube line-stage or buffer amplifier. The circuit uses four 9-pin dual-triode sockets—typically two input tubes and two output tubes—and applies the Aikido topology, which uses balanced tube sections to reduce power-supply noise at the output. It is a bare PCB/design product rather than a complete amplifier: tubes, passive components, power supply or transformer, enclosure, connectors, and controls must be supplied separately. Compatible tube families include many standard 9A/9AJ dual triodes, such as 6DJ8/ECC88/6922, 6CG7/6FQ7, 6H30, 12AT7, 12AU7, 12AX7, 12AV7, 12BH7, 5751, ECC99, and related types, provided the tube pinout and heater arrangement are suitable. The board can be configured for line-stage use or, with an appropriate White cathode-follower output configuration, headphone-buffer applications. Published documentation describes versions with heavy copper, plated-through construction, dual resistor-pad layouts, and provision for coupling capacitors. Exact performance depends strongly on tube type, operating voltages, resistor values, load, power supply, and construction. it appears to be an older GlassWare/Tube CAD Journal DIY PCB design and should be treated as possibly discontinued or legacy stock rather than a currently confirmed production item.