Tubes & Topology
At the heart of the Soul 170P are four TUNG-SOL KT170 beam tetrodes, operating in a Class A push-pull configuration. The amplifier also features:

Voltage Amplification Tubes: 2 × 12AU7

In the voltage amplification stage, two JJ 12AU7 tubes are responsible for initial signal gain, providing the necessary voltage amplification before driving the output stage. Their low distortion and noise characteristics contribute to stable signal handling.

Driver Tubes: 2×6SN7

Employed in the driver stage, the JJ 6SN7, known for its musicality and powerful drive, contributes to a sound that’s both emotionally engaging and analytically revealing.

Rectifier Tube: 1 × 17AX4GT
This classic rectifier tube supplies a stable DC voltage to the driver stage, ensuring reliable performance and a refined sound with beloved tube body musical expression.

Flexible Operating Modes
StereoMode:60W(Ultralinear, per channel)
MonoMode:120W(Ultralinear, per channel)
Users can easily switch between Stereo and Mono operation using a secure rear-panel switch, allowing the Soul 170P to be used in both two-channel and high-power mono configurations.

Negative Feedback Circuitry
To achieve a more refined and natural sound presentation, the Soul 170P employs a carefully tuned Negative Feedback (NFB) circuit. Cayin engineers applied a moderate global feedback loop, striking a balance between control and musical expression. In addition, the Soul 170P features two selectable NFB levels—High and Low—allowing users to fine-tune the amplifier’s sound signature.

Choose Low for a more open, expressive, and emotionally engaging sound, or High for tighter control, improved precision, and a more analytical presentation. This flexibility allows the Soul 170P to fully showcase their character across a wide range of speakers and musical genres.

Dynamic Auto Bias
The Soul 170P features a fully integrated Dynamic Auto Bias servo circuit, allowing seamless power tube replacement without manual adjustment. This system precisely regulates the operating status of each KT170 tube, ensuring optimal matching and extending tube lifespan—all while maintaining operational safety and tube longevity