Teac
Esoteric D-70 DAC, ex-dem, immaculate condition complete with remote control,
box, and paperwork.
The Esoteric D-70 D-A converter is circa 2006, using the Burr Brown PCM1704 DAC
chipsets which are still in production today and used by Naim Audio DAC.
AC
voltage 220-240V.
UK listed
price £6000.00.
Product Information
The D-70
is an advanced D/A (digital-to-analog) converter that can handle multiple
2-channel linear digital source signals. When 176.4 kHz or 192 kHz is used, 2
XLR inputs are used simultaneously to enable stable transmission. (AES 3
standard.)
The Ultimate in Sound
Reproduction Available from the Compact Disc Format
Refined Digital Output
Technology & Refined Asynchronous Memory Link
Handles 24 bit Input with a
Wide Range of Sampling Frequencies (32 to 192 kHz)
Advanced newly-developed Refined Digital Output Technology (RDOT)
The traditional belief is that the upper limit of human hearing is 20 kHz. In
real life, however, information at frequencies over 20 kHz exists, and it is
generally recognized that the presence of this information can significantly
enhance the listening experience. However, when a CD is recorded, on account of
the limitations of the sampling frequency, the audio upper limit is restricted
to 20 kHz. RDOT provides a way to overcome this limitation and break the 20 kHz
barrier, using the Fluency theory. The RDOT filtering utilized in the D-70 is
equivalent to 24-bit/96 kHz input - a significant advance over the current
16-bit/44.1 kHz standard. When this new RDOT is employed, sources with up to
192 kHz sampling frequency, including the latest generation of audio discs, can
be read. Using a higher frequency allows the "gaps" to be filled
between the existing samples, effectively doubling the sampling frequency. The
listener finds it easier to distinguish the sounds of individual instruments,
even when many instruments are playing at the same time, and the quality of
recorded reverberation is significantly improved, resulting in greater realism,
and a much closer approach to a live performance.
TEAC's unique RAM link using new circuitry (Refined Asynchronous Memory
Link)
In order to achieve an ideal jitter-free D/A converter, we have installed a
full 128Mbits' worth of RAM Link buffer at the first stage of the DAC. The
object is for the buffer to eliminate jitter completely, regardless of the
amount of jitter or the frequency bandwidth. This results in an effective
zero-error operation. The large amount of RAM in this buffer allows all
incoming jitter to be absorbed completely in the buffer, and the data to be
transferred, using the internal high-precision clock, to the next stage of the
DAC. Key benefits of using a large RAM Link buffer:
Allows high bit-rate and
high-frequency sampling
Extended continued playback
is possible, and the high RAM
capacity makes it unnecessary to
continually adjust the clock frequency.
In order to produce a
jitter-free stream, the optimum position for a buffer is immediately
behind the digital filter. However, when oversampling takes place, and if
there is a large amount of data to be buffered, then the RAM must be large
enough to take account of this. On the D-70, both these aims have been
achieved, with a buffer whose capacity is enough to handle the demands
made on it
Servo-free direct clocking system
In the D-70, a servo-free direct clocking system is used, which comes close to
the ideal of clock control. In systems where a clock other than the one derived
from the digital audio signal is used, typically PLL (phase-locked loop)
technology is used to keep the clock frequency as constant as possible. However,
in high-end equipment such an approach leads to problems when designing
circuitry that will not compromise the audio quality. The new method employed
in the D-70 to maximize audio quality is to use a DAC locked to a direct
crystal-controlled fixed-frequency clock. This allows the conversion to be
carried out independently from the input frequency and input jitter is
therefore eliminated. In the case of non-synchronization, the RAM Link buffer
mentioned above eliminates any potential problems.
32kHz - 192kHz wide-ranging input sampling frequency, with 24-bit input
The D-70 is an advance
