McCormack DNA-750 Owner's Manual

Beyond

Your

Expectations

Within

Your Reach

DNA-750

Mono

Power Amplifier

McCORMACK

AUDIO CORPORTATION OF VIRGINIA

Thank you for purchasing a McCormack Audio DNA-750 Power Drive. This amplifier was
hand crafted with top quality, highly reliable component parts. We are confident that you
will be well satisfied with its sonic performance and find pleasure in its functional beauty.
Before you enjoy these experiences, however, please take a few minutes to read this
Owner's Manual and acquaint yourself with the instructions for optimal operation. This will
ensure your listening pleasure today, and for many years to come.

DNA-750 Owner’s Manual 1

INSTALLATION

We recommend that you save the box and packing materials. Store them in a dry
environment. It is best to use the original package should you need to transport your
DNA-750 Power Drive.

Place your DNA-750 Power Drive on a stable surface in a location which allows adequate
ventilation. If it is sitting on a carpet, use either a flat board or Tip Toes underneath to
keep the ventilation slots unobstructed. Do not locate it in direct sunlight or expose it to
extremely high temperatures (above 70 degrees centigrade/154 degrees Fahrenheit).
Allow at least four inches of open space on each side, and six inches of open space both
above and behind. Do not block the ventilation slots on the top or bottom, or the heat
sinks on each side.

All DNA-750 Power Drives sold in the United States are configured for operation on a
60Hz ac power line producing between 108 and 126 volts. Export versions of the DNA­750 will have the correct operating voltage and frequency clearly marked on the back
panel of the unit, near the ac power cord. In all cases, the actual line voltage should be
within + 5/- 10% of the nominal rated voltage.

Electromagnetic Interference (EMI)

Considerable care has been taken in the design of the DNA-750 to minimize its
susceptibility to radio freq uency interference and other forms of EMI. Choice of materials,
physical layout, grounding practice, and power supply design have all been specified with
a view to reducing the impact of electromagnetic fields on the performance of this unit. At
the same time, however, our primary goal is the accurate reproduction of recorded music
in the normal home environment, and we have elected not to compromise this objective
by the application of heavy -handed RFI filters, or by using grounding practices that
reduce RFI at the expense of degraded audio performance. We find that the approach we
have taken has worked extremely well, resulting in only rare instances of EMI problems
which could be treated locally as needed, rather than co mpromising the performance of
our product in the 99.9% of installations where EMI is not a problem.

Care in installation can often avoid EMI induced problems. The following practices should
generally be observed in any application, and will be especially important where EMI may
be a problem.

Interconnect cables should be kept as short as possible (3 meters or less), and shielded
cable should be used (cable which has two center conductors, and a separate external
shield connected at only one end).

Physical location and cable “dress” can be an important factor in minimizing hum pickup.
The installation should situate the preamplifier well away from the power amplifier, and
power (ac mains) cords should be dressed to remain at least 4" (100mm) away from
input/output cables.

DNA-750 Owner’s Manual 2