Experiment highlights / Vacuum Tube Amplifier / Invention Discovery Series / Otona no Kagaku product version / otonanokagaku.net

Vacuum Tube Amplifier

The role of battery-powered vacuum tubes

The vacuum tubes in the kit are battery powered, which makes them better suited to experimenting and modification. The directly heated tubes start working as soon as you turn the power on. The tubes use pentode connections for higher volume.

2P3: This is an output tube that amplifies power. It handles the sound output by the speakers.
1B2: The vacuum tube amplifies the voltage.

Specially made pin straightener for straightening the pins at the base of the vacuum tube is also included.

Vacuum tubes cannot be plugged into sockets if the pins are bent. This tool gathers in the tips of the pins and squeezes them to straighten out any bent ones.

Independently-developed multi-cellular horn speakers optimal for the vacuum tube amplifier

The efficient speaker system exploits the power of vacuum tubes to the maximum. Our full-range speaker with 40-diameter mylar cone and neodymium class magnet has an old-school multicellular horn.

Frequency characteristics experiment with a straw

You can test frequency characteristics (magic voice) by inserting straws into the back of the speaker to make the straws resonate.
* Straws are not included.

Independently-developed output transformer

We developed our own irregular EE core transformer with a core material carefully selected to get the most amplification performance from the vacuum tubes.

Experimental modifications of the amp circuit

You can experiment with the circuits to change the sound volume and amplification rate. Make modifications with the triode connection circuit and power-up circuit.
* You will need a soldering iron to make modifications.