Octave V 70 Class A Integrated Amplifier

The V 70 Class A is Octave's Class-A integrated amplifier — a design born from Andreas Hofmann's ambition to bring the bewitching midrange purity of Class-A operation into the tonal profile of Octave's popular integrated amplifiers without accepting the traditional Class-A tradeoffs of low power, limited dynamics, and excessive heat. The result is what Octave calls a Class-A push-pull amplifier in a pentode circuit — a new circuit concept enabled by a new Class-A technology.

The core innovation is Dynamic Bias Control. In technical terms, Class-A means a higher quiescent current setting and therefore lower distortion (almost exclusively second-order harmonics k2), but also limited full modulation with less power. Push-pull concepts deliver 4-16x the output power of Class-A but with inharmonic distortions (odd harmonics k3 and k5). Hofmann's Dynamic Bias Control finds ways to dynamically shift the limited dynamic range and power of the Class-A concept according to requirement — creating a self-regulating Class-A amplifier with approximately twice the output power of conventional Class-A designs: 50W RMS with up to 70W peak (with Super Black Box).

The V 70 Class A uses an auto-bias circuit that self-adjusts to the tube being used and requires no adjustment controls. Octave's proven BIAS measurement with colored LEDs remains available to verify that all four output tubes are working properly. Power preselection (High/Low) allows optimal adaptation to different power tubes: KT 120 or KT 150 for Power High, KT 88 or 6550 at Power Low.

Standard Octave Power Management, Protection System, ECO Mode, Home Theater Bypass, Power Selector, Regulated Preamp Output (for direct subwoofer connection), and (Super) Black Box Connection. Silver or Black chassis. Available at LMC for audition.