Model number TU-8100
Price JPY 29,480 (incl.tax)
[JPY 26,800 (excl.tax)]
Difficulty 1 2 3 4 5
Assembly time5-6 H
Target ageGeneral
Tools required
Phillips screwdriver ,Diagonal cutter ,Longnose pliers ,Scissors ,Pen knife ,Soldering iron


This is a compact single stereo power amplifier kit with multiunit tubes for the audio equipment "PCL86(14GW8).
This amplifier is equipped with 2 line input terminals as the high-sensitivity stereo mini jack (front) which can be directly connected to a portable music player as well as the normal pin for LINE IN (RCA) jack.
AC adapter is used as a power line so that the amplifier can be used worldwide.

Thanks to its structure of generating high voltage for vacuum tubes through the built-in inverter circuit, no hum noise is generated.
With simple modification on PCB, i.e.changing the jumper on the PCB, ECL86 (6GW8) can also be used instead of PCL86 (14GW8) regardless of the voltage difference.

What are done for better sounding;
Regarding the output transformer, the characteristics are improved by large.
In addition, for coupling capacitor, we adopted a PP film capacitor with non-inductive structure.
A special burn-injury protector with damping structure is developed; without interferring heat release, they grip the vacuum tubes from sides and top, and moderate unnecessary oscillation. They come with the amplifier as standard equipment.
For the speaker terminals, screw-type binding terminals are adopted. Commonly used banana-plugs can also be used. The input jacks are gold-plated. (RCA jack and 3.5mm 3-pole jack)

Power control by microcomputer;
A microcomputer is equipped to enable a soft-start and B power delay after heater power soft start - like what a rectifier tube does. Very vacuum tube-friendly sequence.
In addition, problem monitoring is executed for safe operation. For vacuum tube amplifiers, damage to the tubes and parts rarely occurs when the plate current of the output tubes becomes uncontrollable due to an output tube malfunction, a contact failure in the socket, or poor soldering. In this model, the microcomputer monitors the 6 key voltages and shuts down both the heater and the B-power source when there is a problem, and indicates it by flashing LED.
New design;
The basic configuration is a standard vacuum tube amplifier, but it is fit in a very compact chassis; W14xD14(cm), and the operation is also simple; only 1 volume knob so that anyone can intuitively operate. The color is noble metallic (light gray/silver metallic).
Although this requires soldering, all the circuitory factors are already mounted on the PCB, and wiring which some users find difficult is omitted from user assembly stage. Easy to assemble and disassemble, and easily maintained.


Vacuum tube: PCL86 x 2pcs
Rated output: 2W + 2W
Rated input: 500mV(INPUT-1), 150mV(INPUT-2)
Frequency response: 23-33,000Hz
Residual noise: 40microV(IEC WEIGHTING)
Corresponding speakers: 4-8ohm
Output terminal: Binding terminal (Banana plug can be used.)
Supply voltage: DC12V, approx.2A(fixed)
AC adapter: World compatible 12V@4.17A Switch mode power supply
Dimension: W142xH136xD178mm (including projections)
Weight: Approx.1.8kg (excluding AC adapter)