Audio Note DAC-5 Owners manual

DAC5 Special

Owner’s Information

The DAC5 Special is a Level 5 digital to analogue
converter, developed for the best possible sonic
performance rather than technical specifications. To this
end, the DAC incorporates thermionic valve technology
to produce the most accurate sound possible and has
been brought to maturity through a development process
we call comparison by contrast, which is currently
unique to Audio Note. The article from which this
technique is based, named ‘Audio Hell’, is available
from Audio Note by request.

Please read this manual carefully in order to obtain the
best possible performance from your DAC. Audio Note
wishes you many happy years of listening pleasure.

Technology

Extensive research into the fundamental properties of the data stream itself have
shown beyond doubt that regardless of the theoretical and measurable advantages of
the signal manipulation employed in all currently available digital products, such as
higher over sampling, noise shaping, re-clocking or jitter reduction, the result is this:
all these corrective measures greatly interfere with the critical time domain
requirements of the signal, based as current theory is, on an assumption that music is
similar to book keeping data which of course it is not. Music is a time continuum
from beginning to end, which when broken is irreparably damaged and no amount of
clever manipulation can ever restore it to its original time-frequency-amplitude
duration or relationship, regardless of what the theorists may tell you.

The DAC5 Special uses the revolutionary and currently exclusive Audio Note digital
technology dubbed 1x oversampling™ direct from disc™ circuit topology. The
technology in essence dispenses with all the correction measures inherent in all other
D/A converters and presents the digital signal directly to the converter after
reformatting. In other words, all products in the Audio Note DAC range have no
oversampling, no jitter reduction, no noise shaping and no re-clocking. Having
removed all the digital filtering that is part of the oversampling, all filtering is done in
the analogue domain where it appears to be easier to retain good wide band phase­frequency and dynamically coherent behaviour than in the digital domain. The end
result being the reproduction is more reminiscent of master tape in quality.

They use the highest grade Analogue Devices AD1865, 18Bit stereo converter chip
because we found this chip to be the best sounding available (yes, even better than the
20Bit versions!). This is fully compatible with 16-bit 44.1kHz technology as well as
48kHz and can also be used with the 24-bit 96kHz DVD-A standard as the DAC chip
will only loose resolution at the 20th, 22

nd

and 24th Bit, a truncation that mildly reduces

the resolution. Tests have shown that this information loss is inaudible when
compared to comparable methods used in digital technology, which involve either
oversampling, up sampling or other digitally derived signal manipulations or
“improvements”.

The DAC5 Special features Black Gate filter capacitors, Audio Note copper foil
signal capacitors and tantalum resistors everywhere, an ECC82, 6463 zero feedback
output stage, an improved choke smoothed and 6X5, ECL82, OB2 valve rectified
power supply, balanced outputs, Perma 50% nickel double c-core output transformers
and improved I/V interface transformers.

Unpacking & Installation

Please take care when unpacking the DAC5 Special. We recommend that you store
the packing materials in case the unit requires shipping at a later date.

Next, select a suitable location for the unit, ensuring that adequate ventilation is
provided (the valves generate a fair amount of heat). In the interest of safe, reliable
operation, situate the DAC well away from dampness or direct sunshine.

Worthwhile sonic improvements may be obtained by locating the unit on a
specifically designed audio component support system; we tend to prefer natural
materials such as wood.