Bias Adjustment Possible with Just the Press of a Button

The "EL34 Push-Pull Vacuum Tube Amplifier Kit (TU-8340)" employs a fixed bias method while featuring a "Semi-Automatic Bias Adjustment System" that allows for the necessary bias adjustment during vacuum tube replacement with a single touch.

There are broadly two types of vacuum tube bias (voltage): "fixed bias" and "self-bias." For push-pull amplifiers, the "fixed bias" method offers better efficiency and the advantage of compatibility with vacuum tubes of different characteristics.

However, typically, it is necessary to manually adjust the voltage for each vacuum tube while monitoring a meter. Therefore, we developed the "Semi-Automatic Bias Adjustment System" that allows bias adjustment with a single button press. Additionally, because the bias adjustment block is composed of many components, it is provided as a completed module to simplify assembly.


With careful consideration for sound quality as well as ease of use, the amplifier uses non-inductive PP (polypropylene) film capacitors with excellent high-frequency characteristics for the coupling capacitors. Ample space has been secured for replacing these with other capacitors, allowing users to craft their preferred sound. Capacitors of approximately Ø31×57mm in tubular form can be installed.

The TU-8340 is easy for beginners to handle. Why not take this opportunity to savor the profound world of vacuum tube amplifiers?

TU-8340
Dimensions | Approx. W450 x H200 x D336mm
Power Voltage | AC100V 50/60Hz
Input Terminals | LINE x 1
Output Terminals | Speaker Output Terminals (4-6.3Ω, 8-16Ω) Gold-plated screw terminals (banana plugs usable)
Price | ¥118,000 (excluding tax)