All-in-One Custom Kits in stock now! Printed Circuit Boards and kits to match Tube CAD Journal circuit designs. Aikido kits.

Combining the Aikido All-in-One power supply with the CCDA topology allows an excellent tube phono stage to be made easily and inexpensively. The CCDA’s low distortion and output impedance, without the use of negative feedback—all are desirable attributes in a phono preamp.

New SRPP+ PCB and custom kits: PCB, resistors, high-voltage PS and heater PS capacitors, heatsink, solid-state devices, a selection of coupling capacitors and tubes, ceramic tube sockets, and board stand offs—everything that is needed to populate the PCB. Comes 16-page user guide.

New Aikido "All in One" LSA/HPA kit. Aikido 9-Pin stereo PCB, resistors, regulated high-voltage and heater power supplies, capacitors, heatsinks, solid-state devices, ceramic tube sockets, board stand offs, tubes and coupling caps—everything that is needed to populate the PCB available as options.

Aikido "All in One" Line Stage Amplifier Kit octal stereo. Custom Kit: PCB, resistors, high-voltage PS and heater PS capacitors, heatsink, solid-state devices, a selection of coupling capacitors and tubes, ceramic tube sockets, and board stand offs—everything that is needed to populate the PCB.

Aikido "All in One" Line Stage Amplifier Kit 9-Pin stereo. Custom Kit: PCB, resistors, high-voltage PS and heater PS capacitors, heatsink, solid-state devices, a selection of coupling capacitors and tubes, ceramic tube sockets, and board stand-offs”everything that is needed to populate the PCB.

The TCJ Attenuator A3 is an interesting design: a hybrid attenuator that uses both series and ladder attenuators to yield the best compromise between flexibility, performance, and cost.

Aikido Phono-Stage is a stereo phono preamp that uses two Aikido gain stages per channel and passive equalization in between.

The All in One PCB holds two Aikido line-stage amplifiers and includes the heater and high voltage B+ power supplies—all the same PCB. Thus, the All in One board makes building a standard-setting line stage amplifier much easier. The All in One assembled board with a chassis, volume control, selector switch, power transformer, and a fistful of RCA jacks is all that is needed.

The three positions are: all transformers off, transformer 1 on and transformer 2 off, and both transformers on. With this setup, you can turn on the heater transformer first, so the tubes are given a chance to heat up, which will create an electron cloud over the cathodes, protecting them from the B+ voltage.

1.4 by 2 inch, PCBs that hold a single rotary switch and nothing else, other than termination pads for hookup lead. The Select-2 selector switch assembly accepts three stereo inputs, with both the hot and grounds of each signal source to be selected. So if a signal source, say a CD player, is not selected, neither its outputs or grounds make any connection to the line-stage amplifier.

The capacitor selector makes wiring up an Aikido board an easy task, as the two coupling capacitor outputs from each channel attach to the small PCB and the two outputs leaving the switch allow choosing between coupling capacitors C1 or C2 or both C1 and C2 in parallel.

RTI Audio polypropylene-film Capacitors New RTI Audio polypropylene-film coupling capacitors. This is an amazing sleeper of a capacitor. It is made in the USA by RTI Electronics, a 27 year old company that is, as RTIE likes to say, "an industry leader in the design and manufacture of high quality audio/video Teflon capacitors." Which is true, as many high-end capacitors, no matter how labeled, are actually made by RTI Electronics. A huge upgrade in sonics over typical polypropylene coupling capacitors.

Kits are now available without tubes. In addition to the pure-tube line out, the PCB holds a class-A, single-ended, unity-gain, solid-state buffer output stage, for driving low-impedance headphones (32 to 600-ohms).

New Solo high-voltage Janus and PS-2 regulator kits.

New and Improved TCJ Stepped Attenuator Kit

New circuit board! 24V Aikido Tube Line Stage and Headphone Amplifier

9-Pin stereo Aikido PCB boards are four inches by ten inches, with eight mounting holes. Boards are made in the USA and come with schematic and recommended part values and design examples.

This is a stereo Aikido PCB that accepts 5687s in the output tube position. These wonderful and relatively cheap tubes are a natural for driving high-impedance headphones and high-capacitance interconnects.

Octal stereo Aikido PCB boards are four inches by ten inches, with eight mounting holes. Perfect for use with 6SN7 and 12SN7 tubes. Boards are made in the USA and come with schematic and recommended part values and design examples.

Single channel Aikido printed circuit boards for 9-pin tubes. Perfect for stereo and 5-channel systems and for use in monoblock power amplifiers.

A single channel Aikido line-stage amplifier printed circuit board for octal dual triodes, such as the 6AS7, 6BL7, 6BX7, 6SL7, 6SN7, 12SL7, 12SN7, 12SX7, 5691, 5692, 6080, B65, ECC32, ECC33…

Aikido Line Stage Amplifier Kit. Includes tubes, resistors, PS and heater bypass capacitors, two sets of coupling capacitors (PIO and film), two printed circuit boards, ceramic tube sockets, and board stand offs.

Aikido Line Stage Amplifier Kit (octal-based & stereo). Includes tubes, resistors, PS and heater bypass capacitors, two sets of coupling capacitors (PIO and film), printed circuit board, ceramic tube sockets, and board stand offs.

Custom Aikido Line Stage Amplifier Kit (Octal & dual-mono). Select only what you need: tubes, resistors, PS and heater bypass capacitors, two types of coupling capacitors (PIO and film), printed circuit boards, ceramic tube sockets, and board stand offs.

Aikido Line Stage Amplifier Kit (9-Pin & dual-mono). Includes tubes, resistors, PS and heater bypass capacitors, two sets of coupling capacitors (PIO and film), two printed circuit boards, ceramic tube sockets, and board stand offs.

5687-based Aikido line stage amplifier kit. Includes tubes (EH 6CG& & NOS JAN 5687), resistors, power-supply and heater bypass capacitors, two sets of coupling capacitors (PIO and film), printed circuit board, ceramic tube sockets, and board stand offs.