Cayin CS-55A KT88 silver

The Cayin CS-55A KT88 is a stereo integrated tube amplifier, the result of several decades of experience in tube electronics design. It delivers 2 × 40 watts of power in ultralinear mode and 2 × 22 watts in triode mode. This model features a USB digital-to-analog converter compatible with high-resolution files, as well as a phono preamplifier for MM cartridges. It combines traditional analog technologies with modern digital features, all in a carefully crafted design focused on balanced and precise sound reproduction.

Renowned expertise in the world of tube amplifiers

For over a quarter of a century, Cayin has established itself as a benchmark in the field of high-fidelity tube electronics. The brand cultivates a distinctive sound philosophy, favoring a warm and harmonious reproduction reminiscent of the legendary amplifiers of the 1960s and 70s. The CS-55A KT88 fits perfectly into this tradition while incorporating contemporary technologies to meet the needs of modern audiophiles.

This balanced approach between tradition and innovation makes the CS-55A KT88 an exceptional product. Its ability to faithfully reproduce every musical nuance, from the most delicate timbres to the most dynamic passages, is a testament to Cayin’s expertise in the art of tube amplification.

A sophisticated internal architecture

At the heart of the CS-55A KT88 lies a carefully designed architecture that combines premium components with artisanal manufacturing techniques. The amplifier features three oversized transformers—one for power supply and two for output—ensuring stable power delivery and generous power reserves.

The output stage includes four KT88 power tubes operating in push-pull class AB configuration. They are accompanied by two 12AU7 tubes and two 12AX7 tubes for the preamplification and power tube control sections. This strategic combination of eight tubes in total achieves an optimal balance between dynamics and musicality.

One of the major strengths of the CS-55A KT88 is its entirely hand-wired point-to-point construction, a traditional assembly technique prized by audiophiles for its superior sonic qualities. The ventilated chassis with its high-end finish also houses audiophile-grade capacitors, carbon film resistors, and high-quality ceramic tube sockets.

Remarkable sonic versatility

The CS-55A KT88 stands out for its ability to adapt to different listening preferences thanks to its dual operating modes. The ultralinear mode delivers 2 × 40 watts into 8 ohms, emphasizing dynamics and bass extension. For a more intimate and warm listening experience, the triode mode offers 2 × 22 watts with a sound coloration particularly appreciated for vocals and acoustic instruments.

This adaptability also extends to the choice of power tubes. While supplied with KT88 tubes renowned for their tonal balance and bass extension, the amplifier can also accommodate EL34 tubes, which provide a warmer coloration, especially for vocals, at the expense of slightly less extended bass response. A dedicated selector allows you to adjust the transformer windings according to the tube type used, ensuring optimal performance regardless of the chosen configuration.

The frequency response generously extends from 5 Hz to 44 kHz, amply covering the audible spectrum and allowing you to fully enjoy high-resolution recordings.

Successful integration of digital and analog technologies

What truly sets the CS-55A KT88 apart from most traditional tube amplifiers is its built-in USB DAC. This high-quality digital section supports audio streams up to 32 bits and 384 kHz, allowing you to fully exploit the potential of high-resolution digital music from a Mac or PC.

For vinyl enthusiasts, the amplifier also includes a phono preamplifier compatible with moving magnet (MM) cartridges. This dual analog and digital compatibility makes the CS-55A KT88 a complete solution for all music formats, from the most traditional to the most modern.

The elegant anodized aluminum front panel houses a generously sized headphone jack that benefits from the same attention to detail as the rest of the amplifier. Listening tests with high-end headphones such as the Focal Stellia reveal perfect tonal balance and remarkable dynamics, with a sound that is both smooth and precise.

A captivating listening experience

Listening impressions of the CS-55A KT88 are unanimously glowing. The amplifier instantly impresses with its controlled tonal balance and natural dynamism. Its sound signature is characterized by great clarity in the mids and highs, smooth and melodious vocals, and an ability to reproduce the subtlest details.

This combination of smoothness and dynamism prevents any listening fatigue, even after several hours of continuous use. It is precisely this ability to combine analog warmth with modern precision that makes the CS-55A KT88 such an appealing amplifier.

Connectivity and practical features

The CS-55A KT88’s connectivity meets all the needs of modern audiophiles. On the rear panel, you’ll find two RCA line inputs, an MM phono input, and a USB input for computer connection. The speaker terminals are equipped with an impedance selector, allowing you to switch between 4 and 8 ohms for optimal adaptation to different types of speakers.

The streamlined front panel features the power switch, a high-quality Alps volume potentiometer, the source selector, and the headphone output. A Soft-Start circuit protects the transformers and extends their lifespan.

Among the advanced features, there is external bias adjustment with a display instrument, allowing users to optimize tube performance without opening the device. The amplifier also comes with a convenient remote control for comfortable operation from a distance.

Technical Specifications

General Overview

• High-fidelity integrated tube amplifier using KT88 technology
• Dual operating modes:
  • Triode mode for a softer, more intimate sound
  • Ultralinear mode for greater dynamics and power
• Exceptional versatility:
  • Compatible with analog and digital sources
  • Built-in high-resolution digital-to-analog converter
  • Integrated phono preamplifier for turntables
• Sound reproduction characterized by a rich and detailed soundstage, warm timbres, and outstanding musicality

Audio Performance

• Output power:
  • 40 W + 40 W (RMS) in Ultralinear mode
  • 22 W + 22 W (RMS) in Triode mode
• Frequency response: 5 Hz – 44 kHz (–3 dB)
• Total harmonic distortion: 1% (1 kHz)
• Signal-to-noise ratio: 92 dB
• Input sensitivity: 270 mV
• Input impedance: 100 kΩ
• Output impedance: 4 Ω, 8 Ω (selectable)

Connectivity and Inputs

• Audio inputs:
  • 1 × USB (built-in digital-to-analog converter)
  • 1 × Phono MM (integrated phono preamplifier)
  • 2 × Line (CD, AUX)
• Outputs:
  • Speaker terminals with 4 Ω / 8 Ω impedance selector
  • Front-panel headphone output (jack)
• Accessories: remote control included

Digital Section (USB DAC)

• Compatibility: Audio Class 1.0 and 2.0
• Resolution: 16 – 32 bits
• Sampling rate: 44.1 kHz up to 384 kHz
• Compatible operating systems:
  • Windows XP, Vista, 7, 8
  • Mac OS (10.6.3 and above)

Phono Section

• Type: moving magnet (MM) phono preamplifier
• Input sensitivity: 3 mV
• Input impedance: 47 kΩ
• RIAA accuracy: less than ± 0.25 dB
• Total gain: 40 dB
• Signal-to-noise ratio: 68 dB

Architecture and Components

• Tubes:
  • 4 × KT88 (power tubes, compatible with EL34)
  • 2 × 12AX7/ECC83 (preamplification)
  • 2 × 12AU7/ECC82 (preamplification)
• Transformers:
  • 1 × toroidal transformer for power supply
  • 2 × EI output transformers with wide bandwidth
• Construction:
  • Hand-wired point-to-point assembly
  • Audio-grade capacitors
  • Carbon film resistors
  • Ceramic tube sockets
  • Soft-Start circuit

Physical Characteristics

• Dimensions (W × D × H): 360 mm × 334 mm × 180 mm
• Net weight: 17 kg
• Maximum power consumption: 270 W
• Design:
  • Anodized aluminum front panel
  • Vented metal chassis with premium finish

Operating Conditions

• Operating temperature: 0 °C – 40 °C
• Relative humidity: 20% – 80%