UNICO
CD: CD PLAYER
£1,495
Unico CD is an integral part of the Unico range, both in
appearance and in electronic design. It employs
leading-edge technology and features some of the latest and
best components, including D-to-A conversion chipsets from
Crystal and a microprocessor from Philips which takes care
of disc reading and information display functions. All the
necessary information is shown on a large 8192-pixel screen
capable of both text and picture display. The screen is
back-lit and has fully automatic brightness adjustment
which adapts to the ambient lighting to provide ease of
reading at all light levels.
The transport chosen is a high-quality CD-Rom mech normally
used in computers. The motors incorporated in the transport
are of the low-vibration, brushless, asynchronous type. The
laser has a glass lens, which is superior to the plastic
lenses used in most CD players. The guides and supports for
the moving parts of the tray are lapped steel (not
plastic), and the output signal from this transport is an
S/PDIF. As an added bonus this mech is mounted on a rubber
suspension to reduce the possibility of vibration affecting
the reading capability of the laser diode.
Digital signal processing is carried out first by a CRYSTAL
CS8414 chip which provides clock-jitter reduction and
correction and control of the audio data. Next follows the
(optional) CRYSTAL CS8420 chip which takes care of
oversampling at 96kHz, with a clock at 24.576 MHz. The
output from this chip is fed to the CRYSTAL CS9342
converter which has a maximum capability of 24 bit/192kHz.
The signal is filtered by a passive network and sent to a
valve preamp stage which operates in pure Class-A using 1 x
ECC82 double triode for each channel. Audio output signals
are provided in both balanced and low-impedance unbalanced
(>100 Ohms) mode. On the rear panel there is provision
for a digital input and output, in the optional version
with oversampling.
All the electronic circuits are fed from one large,
low-flux power transformer designed specially by Unison
Research for this project. 5 separate stabilized power
supply stages are used, of which the one providing anode
voltage to the valves is a power MOSFET stage.
Input stage
- Double triode ECC82 configured in a first Pure Triode Input Stage followed by a second triode stage with Bias Active Control.
- Anode voltage and heater current (dc) are stabilised.
Output stage
- Improved Dynamic Class A Symmetrical Stage employing a Power MOSFET Complementary Pair