Cayin CS-55A EL34 silver

The Cayin CS-55A EL34 integrated amplifier represents a perfect balance between the warm sound of tubes and the demands of modern music. This carefully crafted model delivers 2x38 watts in ultralinear mode and 2x20 watts in triode mode, allowing it to efficiently power a wide range of loudspeakers. Equipped with an MM phono section for turntables and a high-resolution USB digital-to-analog converter supporting signals up to 32 bits/384 kHz, this amplifier serves as a bridge between the analog and digital worlds.

Thoughtful Design in the Service of Musicality

The Cayin CS-55A EL34 showcases the brand’s expertise with its meticulous construction. The amplifier features three substantial transformers (one input transformer and two output transformers) and a total of eight high-quality tubes. The output stage includes four EL34 power tubes operating in push-pull class AB1 configuration. These power tubes are paired with two 12AU7 tubes and two 12AX7 tubes for the preamplification stage.

The anodized aluminum front panel and the ventilated chassis with its refined finish give the device an elegant look that fits seamlessly into any interior. The hand-wired point-to-point assembly and the soft-start circuit reflect the attention to detail and the durability of the components.

Remarkable Versatility

The CS-55A EL34 stands out for its exceptional versatility. Despite its entry-level position in the Chinese manufacturer’s lineup, it offers comprehensive connectivity with two stereo RCA line inputs, an MM phono input for turntables, and a USB-B input for computer connection.

This extensive connectivity allows you to use a variety of audio sources, from the most traditional to the most modern. The amplifier can thus serve as the nerve center of a complete audio system, capable of playing both vinyl records and high-resolution digital files or online streaming services.

A Dual-Faceted Sound Experience

One of the most remarkable features of the Cayin CS-55A EL34 is its ability to operate in two distinct modes, selectable via the supplied remote control.

In triode mode, the amplifier delivers a particularly warm and textured sound, with a spacious and airy soundstage. This mode is ideal for ambient music, live recordings, or baroque music, where the reproduction of room acoustics is essential. Power is then limited to 20 watts per channel.

In ultralinear mode, the bass response is more extended and the power increases to 38 watts per channel. While the musicality is slightly less pronounced than in triode mode, it remains exceptional compared to a conventional solid-state amplifier. This mode is perfect for more dynamic tracks that require more power.

High-Level Audio Performance

The Cayin CS-55A EL34 offers an extended frequency response from 5 Hz to 44 kHz, which is more than sufficient to fully enjoy high-resolution digital tracks. The signal-to-noise ratio of 92 dB ensures clear and precise sound reproduction, while the input sensitivity of 270 mV allows compatibility with a wide range of audio sources.

When listening, you’ll find the harmonic richness characteristic of tube amplifiers, with an open stereo image and convincing tonal balance. The amplifier handles all registers with authority while maintaining great finesse, provided the paired speakers have adequate sensitivity and do not feature overly complex crossovers.

A High-Performance DAC Section

The digital-to-analog converter built into the Cayin CS-55A EL34 is a major asset for fans of digital music. Via the USB 2.0 input, it can process digital audio signals up to 32 bits/384 kHz, thus covering all currently available high-resolution formats.

This DAC section allows you to connect a computer directly to the amplifier, turning it into a complete audio system for playing digital files or accessing streaming services. The combination of a quality DAC and tube amplification delivers a rich and detailed soundstage, with a characteristic warmth that softens the sometimes excessive harshness of digital sources.

A Phono Section for Vinyl Enthusiasts

The integrated phono preamplifier is compatible with moving magnet (MM) cartridges, allowing you to connect a turntable directly without the need for an external preamp. For moving coil (MC) cartridges, however, an external preamplifier will be required.

This phono section offers an input sensitivity of 3 mV and an input impedance of 47 kohms, standard values that ensure compatibility with most turntables equipped with MM cartridges. The signal-to-noise ratio of 68 dB guarantees clear reproduction of vinyl records, with minimal background noise.

Comparison with the KT88 Version

The Cayin CS-55A is also available in a KT88 version, which uses different power tubes. The EL34 version presented here stands out for its slightly warmer sound, especially appreciated on vocals, but at the expense of a less extended bass response.

The KT88 version, on the other hand, offers a different sonic balance, with greater authority in the bass range, but slightly less finesse and transparency in the mid and high frequencies. The choice between these two versions will therefore depend on listening preferences and the speakers used.

Technical Specifications

Construction and Design

• Handcrafted build with high-quality point-to-point wiring
• Two wide-bandwidth EI output transformers
• Specially designed toroidal transformer for power supply
• Audio-grade capacitors and resistors for smoother and more accurate sound reproduction
• Japanese-made ALPS motorized potentiometer
• Easily installable tube protection

Amplification and Tubes

• Preamplification tube configuration: 2 × 12AX7/ECC83 and 2 × 12AU7/ECC82
• Amplification stage: 4 EL34 tubes in push-pull class AB1 configuration
• Switchable between triode and ultralinear modes
• Output power:
  • 20 W + 20 W (RMS in triode mode)
  • 38 W + 38 W (RMS in ultralinear mode)
• External bias adjustment with BIAS indicator on top of the amplifier
• External tube selector (EL34 / KT88) on the rear panel for easy replacement

Audio Performance

• Frequency response: 5 Hz ~ 48 kHz (-3 dB)
• Total harmonic distortion: 1% (1 kHz)
• Signal-to-noise ratio: 92 dB
• Input sensitivity: 280 mV
• Input impedance: 100 kΩ
• Output impedance: 4 Ω, 8 Ω

Connectivity

• Four pairs of inputs: USB, PHONO, CD, AUX
• Compatible with various audio sources

USB DAC Section

• High-performance USB audio technology using USB 2.0
• High-resolution digital signal decoding 32-bit / 384 kHz
• Internal USB DAC with asynchronous clock
• Compatible with Audio Class 1.0 and 2.0
• Resolution: 16 - 32 bits
• Sampling rate: 44.1 kHz up to 384 kHz
• Supported operating systems: Windows XP, Vista, 7, 8, Mac OS (10.6.3 and above)

PHONO Section

• Input sensitivity: 3 mV
• Input impedance: 47 kΩ
• RIAA errors: less than ±0.25 dB
• Total gain: 40 dB
• Signal-to-noise ratio: 68 dB

Physical Characteristics

• Dimensions (W × D × H): 360 mm × 334 mm × 180 mm
• Tubes used: 2 × 12AX7/ECC83, 2 × 12AU7/ECC82, 4 × EL34
• Net weight: 17 kg
• Maximum power consumption: 270 W

Additional Features

• Remote control included
• Soft start function (about 30 seconds)
• Memory of last operating state after shutdown

Operating Conditions

• Temperature: 0 °C ~ 40 °C
• Humidity: 20% ~ 80%