Operations Manual
AD122-96 MKIII
MKIII PREFACE
The MKIII is our 4
th
generation gold series analog to digital converter.
The first gold AD, model AD122 (developed under our old company name – dB Technologies)
was the first converter to reach 122dB dynamic range which is 20 bits of true performance.
While most AD converters specify dynamic range with an “A weighing” curve - a method which
reduces “the accountability” of lower and higher audio frequencies, Model AD122 provided a
122dB with no A weighing.
The second generation converter, The AD122-96 provided was an extension from the standard
44.1-48KHz sampling rate to “double speed” (88.2 and 96KHz sampling). The double speed
range dynamic range was lower then the standard range, and it was upgraded to the AD122
MKII.
The MKII provides 127dB dynamic range (without A weighing), and a consistent clean
performance over the frequency range. The much improved clock scheme provides extremely
low jitter with both internal and external lock. Achieving the state of the art performance
required increased usage of power, with much of it converted to heat. The MKII runs very hot,
which does reduce its reliability.
The MKIII is a redesign of the MKII, with a strong emphasis on heat reduction. The new
converter modules, housed in metal enclosures with massive heat sinks. A new MKIII
motherboard incorporates all of the previous MKII revisions and is powered by a new power
supply, with better control over DC voltages and power dissipation. The clock circuitry is the
same as the MKII. The software is very stable and left unchanged, therefore the features are all
identical to a MKII. The main benefit of much reduced heat is increased reliability. And last but
certainly not least, is the benefit from even lower distortions over the whole frequency range.
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