Усилители мощности стерео — Cayin Soul 170P

The Soul 170P is the stereo valve power amplifier that Cayin, the Chinese maker of tube electronics, lists as the flagship of its Soul series and as the partner to the Soul 170C preamplifier. It is the first Soul model built around Class A operation. Launch was set for November 2025 at EUR 7,500, in matte black with side panels of solid North American walnut.

Key specs that matter

Four TUNG-SOL KT170 beam tetrodes run in push-pull Class A and give 2 x 32 W RMS in triode mode or 2 x 60 W RMS in ultralinear mode. Bridged to mono, one chassis delivers 64 W in triode or 120 W in ultralinear. Frequency response spans 8 Hz to 70 kHz at -3 dB, and distortion is 0.2% at 1 W and 1 kHz, under 2% at rated output. Signal-to-noise ratio is 105 dB through RCA and 102 dB through XLR. Input impedance is 18 kOhm, and sensitivity is 820 mV with low feedback or 960 mV with high feedback. The chassis measures 430 x 420 x 238 mm, weighs 37.5 kg and draws up to 420 W from the wall.

Engineering and use context

Voltage gain comes from two JJ 12AU7 valves and the driver stage from two JJ 6SN7, while a 17AX4GT valve rectifier feeds the supply through a custom toroidal power transformer. A Dynamic Auto Bias servo watches each KT170 and keeps it at its operating point, so a replacement set of output valves needs no manual bias work. Two negative feedback levels can be selected, and a switch moves the output stage between triode and ultralinear connection, trading power for the triode mode figures above. Every unit is hand built, and its point-to-point wiring and silver-plated internal cabling are there to keep signal loss and crosstalk low. A soft-start circuit and MCU-controlled protection logic look after the valves during switch-on and use, the front panel is brushed aluminium, and removable covers guard the tubes.

Pairing

Selectable XLR or RCA inputs accept the Soul 170C or any line-level preamplifier or DAC with volume control. Separate 4 ohm and 8 ohm output taps let the transformers match the nominal load of the chosen speakers. Speakers with moderate to high efficiency suit a single unit in stereo, while owners of harder loads can buy a second chassis and run the pair as mono blocks.

Alternatives

The Cayin M-845D is the brand's other power amplifier, built as a mono block rather than a stereo chassis.