Naim CD555 CD Player
The CD555 Digital-to-Analogue Converters are mounted in a "quiet room". Apart from ensuring that all critical signals reaching the DAC have immeasurably low jitter the chips are inside a shielded enclosure to keep their environment free of the varying electric and magnetic fields that inevitably occur in a CD player, so enabling the converters to do their work isolated from all external influences.
Key features of this fabulous player include a separate power supply from a transformer secondary winding, which is triple regulated, right through to the critical master clock and de-jittering circuitry. Special attention has also been paid to reducing capacitive coupling of high frequency noise from other supplies into this super quiet clock supply through interconnect cables and wiring looms. Two Burndy interconnects between the power supply and head unit discretely carry the digital and analogue supplies, and extend the principle of reducing capacitive coupling between power supplies as far as possible.
The power supply incorporates significant upgrades over existing designs. More regulators have been used to isolate the supplies to various parts of the circuit, minimising their interaction.
Other noteworthy design features of the CD555 include:
Machined, heavy, solid, transport tray to reduce resonance and vibration amplitude.
High mass design to improve suspension characteristics, providing isolation from the chassis and other components.
Low infra red reflective coatings around the CD to reduce eye pattern interference and noise.
Extremely low inertia and low resonance CD clamp.
Philips CD-Pro mechanism with a die-cast chassis.
Very heavy brass sub-chassis - separate for digital and analogue electronics.
Analogue stages, I-to-V conversion, filtering and output driver are built from discrete components.
Seven-pole output filters.
Separate low jitter clock circuit with its own multi-stage regulated power supply.
Post-digital filter de-jitter circuitry to eliminate jitter.
DACs are isolated from electric and magnetic fields.
Motorised top loading door.
Design features of the 555 PS include:
Seven regulated power supplies including a separate one for the clock circuitry.
Five secondary windings on the transformer.
A transformer that is 40 per cent larger than that in the XPS2.
Separate dedicated analogue and digital output sockets (Burndy) to minimise high frequency noise modulation of analogue supplies.
Backward compatibility with the CDS3 and CDX2.
Can be used to enhance the performance of the Naim HDX hard disk player or DAC.
A low resonance case with isolating feet.
Analogue Outputs DIN, RCA
Line Outputs Fixed (level) 2.1V rms at 1kHz
Output Impedance 10Ω maximum
Minimum Load Impedance 10kΩ
Frequency Response 10Hz – 20kHz, +0.1/-0.5dB
thd+n <0.1%, 10Hz -18kHz at full level
Phase Response Linear phase, absolute phase correct
De-emphasis ±0.1dB referred to main response
Infra Red RC5
Remote Input RCA on rear (RC5)
RS232 RJ45 (fitted but optionally connected)
CD Formats Red Book
Disc Compatibility CD, CD-R, CD-RW
Power Supply Options 555PS, 2 x 555PS
Dimensions 114 x 432 x 314mm (H x W x D)
Front Brushed and black anodised
Case Brushed and black anodised
Naim CD555 CD player