Accuphase DP 70 Brochure

Page 2

Discrete D/A Converter That ACCUPHASE Boats To The World
Incorporates GIG Type 5-Pole Low-pass Filters & Four-times
Dversampling Digital Filters

In the analog disc world. components such as
tape recorders, cartridges. tone arms. and
headshells have their own effects that modify the
original sound However, in a digital system in
which the Signals are encoded and processed.
such modification of the actual sounds hardly
takes place. A defective digital system may
cause dropout or distortion of sounds. In de-
veloping a digital system, therefore. the utmost
emphasis must be placed on how to prevent
such dropout and distortion of the actual sounds
and to improve the system's performance up to
the theoretical upper limit before pursuing perr
fection of sound quality, This should be the basic
policy of manufacturers of digital audio systems.
Without adhering to this policy. manufacturers
should never attempt anything that may result in
modification of the actual sounds nor attempt to
compensate for the dropped out or distorted
sounds by means of sound modification
technique,

In developing a digital audio system. there is
one problem to be solved. Since digital signals
contain radio-frequency noise components in a

wide range. extending up tothe bandwidth equi- .

valent to VHF band of TV broadcasting frequen-
cy. these noise components interfere with the
audio signals and cause inter-modulation distor-
tion. which degrades the sound quality This
degradation is sometimes witnessed when aur
dio equipment is placed very close to a compur
ter radiating strong spurious waves, Therefore,
eliminating the interference of the digital signal
and radio-frequency noise inside the equipment
and eliminating the spurious radiation from the
equipment are important points in improving the
sound quality. To suppress the radioefrequency
noise components. the applications of radio-
frequency technology is indispensable. Conse-
quently. it can be said that digital audio equip»
ment is not refined by digital Signal technology
alone. but through a unique integration with
other disciplines based on radio-frequency
technology and audio technology.

With this philosophy in mind. Accuphase has
developed a CD player in which theoretical up-
per-limit performance is achieved.

The quality of the sounds recorded in a studio can be
reproduced with utmost faith in your own listening room. This is
why the digital audio system is so attractive with the growing
acceptance of CD technology, In short. a new era of listening
excellence is unfolding in the audio world.

To prepare for the advent of this Digital Audio Era. Accuphase
has been focusing for years on the development of the best CD
players possible. And so now enters the DP-70, which is the
cream of Accuphases lastest technology, This is a completely
new. one-ol-a-klnd CD player that provides extraordinary

performance and deep listening satisfaction.

With this philosophy in mind. Accuphase has
developed a CD player in which theoretical up-
per-limit performance is achieved.

The D/A converter, which converts a digital sig-
nal to an analog signal. is the heart of the CD
player, The DP-70 uses discrete D/A converters
which employ supervprecision. highvperformr
ance elements.

The discrete D/A converter is employed in the
DP-70 to obtain the theoretical-iimit-precision in
16-bit digital-to-analog conversion. With the dis-
crete D/A converter. a total distortion. close to
the theoretical-limit and extremely difficult to
obtain with the LSI converter is achieved.
Filters are employed to eliminate highrfrequency
noise components contained in the analog sig»
nal. These highrfrequency noise components
interfere with the audio signal. ln the DP»70, the
most advanced 5-pole GIC type Butterwonh
IowApass filter and four-time oversampling digi-
tal filters are employed. The band-pass ripple cf
the digital filter is plus or minus 0,00005dB,
Additionally. the attenuation of -100dB is
achieved. These can be said to be amazing

values.

The digital circuit and analog circuit are electrie
cally isolated by employing optocouplers. so
that digital signals are input to the D/A converter
through super-high-speed optocouplers. In ad-
dition. the digital and analog circuits have their
own independent power supply to maintain their
isolation.

The DP»70 weighs 21 kg and belongs among the
extremely heavy class of CD players. This heavy
chassis is extremely effective to kill vibration and
resonance generated by the disc drive system.
Emphasis is placed on the simplicity of opera-
tion. Only four keys appear on the front panel,
Other controls keys are hidden in the subpanel
at the lower part of the front panel. Therefore.
you can operate the DP-70 as if you are operat-
ing a conventional analog player. The DP-7r j
be fully remote controlled by the remote mn-
mander attached as an accessory. We believe
the appearance of the DP-7O on the market will
contribute toward up grading the quality of CD
players in the audio industry.

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