Интегральные усилители — Octave Audio V 80 SE

Octave Audio of Karlsbad, Germany, has built the V 80 SE around a push-pull pentode output stage with two output valves per channel. Octave fits four KT 88 valves as standard and offers four KT 150 as an option. Beyond the loudspeaker outputs it has a headphone amplifier, and an MM or MC phono board can be added.

Key specs that matter

Octave rates the V 80 SE at 120 W RMS and 150 W peak per channel into 4 ohm, and 80 W per channel into 8 ohm. Frequency response is 10 Hz to 80 kHz. Distortion stays at 0.1 percent with 10 W into 4 ohm, and Octave quotes -103 dB signal to noise. Input sensitivity is 300 mV on both RCA and XLR, with input impedance of 40 kohm on RCA and 25 kohm on XLR. Minimum load impedance is 2 ohm. The chassis measures 451 x 175 x 415 mm and weighs 23.4 kg. Consumption is 30 W in Eco mode, 180 W idle and 500 W at full power.

Engineering and use context

The driver section uses two ECC82 valves as power amplifier drivers, one per channel, and a shared ECC81 or 6072 as the input valve. A power selector adapts the output stage to the fitted valves. The HIGH position is for KT150 and KT120, and the LOW position takes KT88, 6550, KT90 or KT100, and EL34 with restrictions, with output limited to 2 x 70 W. Valves of type 6L6, KT66, 5881, EL519 and EL156 are listed as unsuitable. Octave notes that the pentode topology keeps the valves within their specification limits. A bias measurement system lets the owner check and set the idle current of all four output valves in a low or high setting. A three position switch selects loudspeakers only, loudspeakers and headphones together, or headphones only, in which case the valve output stage stays off. If Eco mode is on when switching back to loudspeakers, the amplifier waits for a music signal before starting. The headphone output uses a 6.3 mm jack for loads above 200 ohm with distortion below 0.008 percent at 200 ohm.

Pairing

There are six RCA line inputs, one of them a bypass for a home theatre processor and one wired to the optional phono board, plus one XLR input. Outputs include an adjustable RCA preamplifier output for a power amplifier or subwoofer and an RCA tape record output. The Black Box and the larger Super Black Box are passive power supply extensions that add capacitance.

Alternatives

The Octave V 70 Class A is an integrated amplifier from the same V range that runs its push-pull pentode stage in Class A.