Invented in the laboratories of the Bell telephone company in 1938 for telephony applications, it enabled the development of more powerful relay transmitters to support the rapidly developing network.
The characteristics of this tube are proven without doubt and drew the attention of engineers in the cinema industry who, with the coming of sound to motion pictures, were looking to equip theatres with high quality sound installations. The innovation did not escape pioneering HiFi engineers either who, in turn, adopt it to create amplifiers until now unseen.
The 300B triode was such a good development that it remains, even today, an unbeatable component for building exceptional amplifiers. Its linearity, low distortion and natural harmonic response close to ideal leaves modern transistors in its wake.
Remote-controllable, it is equipped with 4 inputs and having all the different audio controls grouped on the front face. Although it was built around a historical component, the 300B triode, the Nagra 300i amplifier is by no means nostalgic or historical electronically. The approach was to surround the tubes with the most evolutionary technology possible so as to draw the maximum musical quintessence to offer a more global and comfortable use.
The 20 watts RMS power per channel achieved is generous, bearing in mind the type of tube being used. It drives all medium to high sensitivity loudspeakers, which are numerous in todays’ market. The biasing of the latter is easily done by the user, who benefits from the indications on the modulometer located on the front face of the amplifier. This instrument is also able to display the output power of the amplifier and the correct impedance matching between the amplifier and the loudspeakers, making connection to the connectors on the rear of the unit easier.