Owner`s manual

Preface
Please take the time to carefully read this instruction
manual prior to installation or use of your Reference CD7
compact disc player. Because it is a highly advanced elec-
tronic instrument, there are several facts and procedures
you should know before you place it in operation.
Introduction
We believe the CD7 breaks new ground in the retrieval and
transmission of digital data from the CD format. In fact,
that's a large part of the fun: just as in the past, when a
new cartridge and tonearm combination brought music to
life with startlingly improved resolution, subtlety and
dynamics, so too you will discover layers of musical infor-
mation you never knew were there in the mirrored surface
of the compact disc.
What's the reason for this superior performance? Well, a
look inside the CD7 reveals a wealth of proven Audio
Research design philosophy. Circuit boards are Audio
Research engineered, with robust construction, careful
hand soldering and layouts optimized for lowest digital
noise. Sophisticated electronic “jitter stripping” techniques
help minimize jitter in the overall circuit. Advanced
massive power supply design, with two transformers and
extensive regulation, has proved crucial even in digital
applications like the CD7. The BNC and XLR digital outputs
are transformer coupled and are driven by a high-current
balanced line driver. Mechanical damping theory has also
been applied to internal mounting of key components and
to critical aspects of the transport and chassis structures
(including tuned polymer feet), to minimize vibration-
induced noise.
Both the analog output stage amplification and the power
supply regulation are all-tube and handled by a total of
seven class A triode operation 6H30 vacuum tubes (four
for the analog stage and three in the power supply).
A bitstream digital-to-analog converter and a high-current
pure class A analog output stage allow the CD7 to be used
with a line-level preamplifier or integrated amplifier. Both
single-ended (RCA) and balanced (XLR) outputs are includ-
ed. Alternatively, the owner may use the CD7 as a high-
quality CD transport in conjunction with an external digital
processor.
The CD drive mechanism itself represents the latest think-
ing from digital engineers, and offers performance clearly
superior to older drives. In part, this is because even the
servos of the CD7 drive operate fully in the digital domain,
whereas older transport models were actually hybrid
designs using analog servos, which placed greater demands
on power supply reserves. The CD7 laser also has a
superior eye pattern for more effective resolution of CD
data and, again, lower jitter.
In appearance, the CD7 is pure Audio Research: heavy
bevelled front panel, with handles flanking the controls on
the right and the readout display on the left. Both controls
and display readout are recessed within bevelled openings
for a more sculptured appearance. A convenient handheld
remote control of all front-panel functions and additional
functions is also included.
On the rear chassis panel you will find BNC coaxial and
XLR digital outputs. (An RCA/BNC adaptor is included with
each unit.) Analog outputs include single-ended (RCA) and
balanced (XLR).
Warnings
1. To prevent fire, or shock hazard, do not expose your
CD7 to rain or moisture.
2. This unit contains voltages which can cause serious
injury or death. Do not operate with cover removed.
Refer servicing to your authorized Audio Research dealer
or other qualified personnel.
3. The detachable power cord on your CD7 is equipped
with a heavy gauge, 3-conductor cable and a standard
three-prong grounding plug. For absolute protection, do
not defeat the ground power plug. This provides
powerline grounding of the CD7 chassis to provide
absolute protection from electrical shock.
4. For continued protection against fire hazard, replace the
fuse only with the same type and rating as specified at
the fuse holder.
5. Do not operate the CD7 player without the supplied
CD7 clamp installed on the CD.
6. Whenever the CD7 is powered up the door covering the
drive mechanism/tray area should remain closed after
inserting or removing a CD, so as not to block the front-
most ventilated area of the top cover. Following this
procedure will maintain proper ventilation and also mini-
mize dust intrusion on the lens and drive mechanism.
Packaging
Save all packaging in a dry place away from fire hazard.
Your CD7 compact disc player is a precision electronic
instrument and should be properly cartoned any time ship-
ment is made. You may not have occasion to return your
unit to the factory for service, but if that should prove
necessary, or other occasion requiring shipment occurs, the
original packaging will protect your CD7 from unnecessary
damage or delay.
Model Reference CD7
1