Cayin Soul 170P Flagship Class A Push-pull KT170 Tube Power Amplifier

Cayin Soul 170P Class A KT170 Tube Power Amplifier

The Cayin Soul 170P combines over 32 years of Cayin's vacuum tube expertise with a powerful Class A push-pull design. Featuring four TUNG-SOL KT170 power tubes, it delivers rich musicality, natural detail, and impressive dynamics.

As the first Class A amplifier in Cayin's Soul Series, the Soul 170P offers selectable Stereo and Mono operation, adjustable negative feedback, and Dynamic Auto Bias for outstanding performance and flexibility.

Key Features

• Class A Push-Pull Design: Four TUNG-SOL KT170 power tubes deliver natural, dynamic sound.
• Stereo & Mono Modes: 60W per channel in Stereo or 120W in Mono (Ultralinear).
• Selectable Negative Feedback: High and Low settings for personalized sound tuning.
• Dynamic Auto Bias: Automatically regulates power tube operation without manual adjustment.
• Point-to-Point Wiring: Hand-assembled construction minimizes signal interference.
• Premium Transformers: Custom toroidal power transformer and wide-band EI output transformers.
• Advanced Protection: 60-second soft-start, MCU protection, and tube fault monitoring.
• Flexible Connectivity: Balanced XLR and RCA inputs with 4Ω and 8Ω speaker outputs.

Premium Vacuum Tube Configuration

The Soul 170P features a carefully selected tube complement for musicality, clarity, and reliable performance.

• 4 × TUNG-SOL KT170: Class A push-pull power amplification.
• 2 × JJ 12AU7: Low-noise voltage amplification.
• 2 × JJ 6SN7: Driver stage for precise, dynamic performance.
• 1 × 17AX4GT: Rectifier tube supplying stable DC voltage to the driver stage.

Stereo & Mono Operation

The Soul 170P supports two operating modes to accommodate different speaker and system requirements.

• Stereo Mode: 60W × 2 (Ultralinear)
• Mono Mode: 120W (Ultralinear)

A secure rear-panel switch allows easy selection between Stereo and Mono configurations.

Selectable Negative Feedback

Two negative feedback (NFB) settings allow users to adjust the amplifier's sound character.

• Low NFB: More open, spacious, and expressive sound.
• High NFB: Tighter control, greater precision, and improved focus.

Dynamic Auto Bias

The integrated Dynamic Auto Bias servo circuit automatically regulates each KT170 power tube, eliminating manual bias adjustments while supporting consistent performance, operational safety, and tube longevity.

Premium Construction

Hand-assembled point-to-point wiring and carefully selected components help minimize interference and preserve signal integrity.

• Silver-plated internal wiring
• Custom-wound toroidal power transformer
• Wide-band EI output transformers
• Aluminum alloy anti-resonance feet

Intelligent Protection

• 60-second tube soft-start circuit
• MCU-controlled protection system
• BMI indicators for power tube fault detection
• Automatic safety protection during abnormal operation

Technical Specifications