Large triode 212E

The 212E is a transmitter and modulation tube with a plate loss of 275 W, developed by Western Electric in the 1910s. Class-A single tube amplifier has difficulty driving a low efficiency speaker, but this unit has a plate voltage of 1,400 V and an output of 40 W. The damping factor of 5 or more is achieved by reducing the output power, so it can drive the low frequency range reliably.

*Two models are available: STC's 4212E (1960-70s production) and Jinzhou Electronics's 212E.

Two-stage configuration with C3g

Equipped with the ultra-reliable C3g, developed by Deutsche Telekom for telephone repeaters. The thin grid lines and large distance between electrodes enable high linearity amplification. Using only two tubes of amplification with the 212E, harmonics and mixed-modulation distortions are suppressed though no-feedback.

High fidelity input transformer

The input transformer makes up for the lack of gain in the two-stage amplification. It is received by a high linearity transformer with a high permeability super permalloy core and does not add anything extra.

* The input impedance is 1.5 kΩ, and should be driven by equipment with an output impedance of 300 Ω or less.

Original regulated power supply

We utilize a dual regulated power supply with a switching regulator in the first stage and an after-analog regulator in the second stage, which has been optimized for audio based on many years of knowledge in power supply development.

Changes from 212PA

Additional Input Connections; Balanced inputs have been added to provide greater connectivity.

Capacitors in High Voltage Power Supply; Polypropylene capacitors have been used instead of oil capacitors to achieve a clearer sound.