BAT VK-80i Amplifier: Automatic Biasing on 6C33C-B Output Triodes

BAT VK-80i Amplifier
BAT VK-80i Amplifier

The Balanced Audio Technology (BAT) tube amplifier, model VK-80i, uses 6C33C-B output triodes with a fully balanced signal path.

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For 55 watts per channel, the VK-80i uses four 6C33C-B outputs, which means it’s far superior to the common 6550/KT90 tube tetrodes.

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There are no traditional fuses in the circuit – in case of abnormal operation parameters of the output stage, the VK-80i goes into safe mode. After that, it is enough to turn it off and on again, which will restore normal operation. The fuseless protection circuit is combined with an advanced automatic bias circuit. There is no need to manually set and adjust the correct output lamp offset. The auto offset circuitry also ensures that your VK-80i will sound great for the first few minutes of listening.

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The manufacturer has documented a THD level at full power of 3%. Frequency range – from 8 Hz to 200 kHz, power consumption 400 W in standby mode, 800 W – at full power. Input switching – 1 XLR, 3 RCA. Volume control – resistive ladder, 90 steps, 1 dB per step. Comes with a full metal remote control. The Balanced Audio Technology (BAT) tube amplifier, model VK-80i, is available in silver or black.