Power amplifiers stereo — Orpheus Lab Absolute Stereo Amplifier A Three S200

The A Three S200 is the two-channel power amplifier in the Absolute line from Orpheus Lab, a company founded in 2001 in Switzerland that designs, assembles and tunes its products in Yvonand. The Absolute range also includes the Absolute 22D preamplifier, the A Four I200 integrated and CD and SACD players, and the S200 carries over technology developed for the Opus II series of the Heritage line. The chassis is anodised aluminium with curved edges.

Key specs that matter

Rated output is 200 W per channel into 8 ohm in Class AB, and the amplifier can deliver instantaneous peaks of 850 W (56.7 V, 15 A) for up to 200 ms. Gain is 26 dB through the XLR inputs and 32 dB through RCA, with input impedance of 94 kohm balanced and 47 kohm unbalanced, and maximum input levels of 2 Vrms and 1 Vrms respectively. THD+N is 0.004% (-88 dB) at full power into 8 ohm at 1 kHz and 0.001% without a load. Dynamic range exceeds 114 dB balanced and 112 dB unbalanced. Bandwidth is flat within 0.1 dB from 5 Hz to 24 kHz and reaches 0.7 Hz to 85 kHz at the -3 dB points. Orpheus quotes an output impedance of 0.0 ohm and a damping factor above 3000. The unit measures 440 x 420 x 148 mm, weighs 30 kg and draws up to 930 W.

Engineering and use context

Each channel uses six hand-matched high-resolution MOSFETs in its current stage, and every one is governed by a bipolar control stage inside a multi-point feedback topology. The layout is dual mono - each channel has its own 880 VA toroidal transformer and 48 mF of reservoir capacitance. A bias current of 125 mA gives an idle dissipation of 15 W per channel, and at rest the unit settles about 15 degrees C above ambient. Protection trips on overload above 9 A peak, blocks DC components below 5 Hz and mutes the outputs automatically when the mains supply is interrupted.

Pairing

The balanced gain and input ceiling match a balanced preamplifier like the Absolute 22D from the same range, while the higher RCA gain lets a single-ended source or preamplifier with a lower output level reach full power. The high current capability and very low output impedance let the S200 hold control over low-impedance or difficult multi-way loudspeakers, and its power rating covers large floorstanders in bigger rooms.

Alternatives

The Orpheus Lab Heritage Ultimate Power Amplifier is a larger stereo model from the Heritage line, rated at 2 x 250 W and switchable to mono or bi-amp operation.