Cyrus Classic PRE
The latest update to a preamplifier that has been part of the Cyrus product range for over a decade.
This preamplifier provides a significant step up in performance from previous versions by using everything that Cyrus learnt when developing the fantastic XR Series, but retaining the familiar design of the Classic series. The circuit design has been completely re-designed and the majority of the internal components have been upgraded by the Cyrus R&D team, which has resulted in sound improvements that will help the Classic series retain a loyal fan base for years to come.
The analogue preamp features relay input selection for the five analogue inputs and a precision gain control for volume. The design is intentionally wide bandwidth.
Phono MM Input
The phono MM input stage design features dual active gain stages and passive RIAA equalisation.
The unbalanced outputs are provided for close wired systems where the power amplifier is located close to the Classic PRE. The balanced outputs are recommended for longer cable runs in systems where the Classic PRE is driving power amplifiers placed close to the system speakers or active speakers.
High Capacity Power Supply
The Classic PRE power supply includes a 74VA toroidal power transformer delivering power to a high capacity power supply reserve. Within the circuit design, a total of 11 independent power supply regulators regulate, then sub-regulate quiet power. Digital control circuits are assigned a separate mains power supply, completely isolated from the signal circuitry.
The Classic PRE includes a port for the PSX-R power supply. Power from the PSX-R is routed internally to the analogue stages of the preamplifier to provide a more stable, low-noise power supply for the analogue preamp and post-DAC stages of the D/A converter.
Power SupplyVoltage: As plate on rear of unit
Dimensions (WxHxD): 215 x 75 x 365mm
Material: Die cast chassis
Line audio performance
Input Impedance Line: 28kΩ
Output impedance Line: 47Ω
Output impedance Bal (per phase): 47Ω
Max input voltage: Line: 2.5V
System gain Line: 6dB
System gain Bal: 12dB
Max output voltage Line: 2.5V
Max output voltage Bal: 5V
Frequency Response (-3dB) Line: <0.5Hz, >100kHz
Signal to Noise Ratio (unwtd) Line (ref 2V out): 110dB
THD Line (ref 2V out): <0.001%
Phono audio performance
Input Impedance: 47kΩ
Max input voltage (1kHz): 25mV
Phono stage gain (1kHz): 40dB
RIAA tolerance: <0.5dB
Signal to Noise Ratio (unwtd) (ref 2V out): 83dB
Digital audio performance
Input voltage: 500mV pk-pk
Input Impedance: 75Ω
Sample rate range (SPDIF): 32k - 192k
Audio formats (SPDIF): PCM stereo
S/N ratio (unwtd) (Pre-out, 0dB fs): >97dB
THD (Pre-out, 0dB fs): <0.003%
Recommended headphone impedance: 16Ω - 330Ω
Output power (16Ω load): 138mW
Max output voltage (330Ω load): 1.85V
Signal to Noise Ratio (unwtd) (35mW//16Ω): 90dB
THD (35mW//16Ω): <0.01%