8
SPEAKER WIRING
Diamond Audio recommends using speaker wire of at least 16 gauge.
Lay out the wire in the vehicle from the individual speaker locations to the
amplifier(s). Observe safe wiring precautions.
Your
D7 Professional Reference Series Amplifier
will accept speaker wire
up to 10 gauge directly. Locate the speaker terminal block on the end of the
amplifier. Strip approximately 1/2 inch of insulation from the wire, insert
the wire into the terminal, and tighten the Allen screw. Repeat for all speaker
wires. Please observe our recommended minimum speaker impedances to
prevent possible damage.
Banana Jacks using up to 8 gauge wire can be inserted into the speaker block.
Remove the set screw completely and insert the Banana Jack into the end of
the block.
The two sets of speaker outputs on the D7401 are paralleled inside the
amplifier for convenience in installation.
CROSSOVER SECTION
All Diamond Audio D7 amplifiers employ the most flexible internal crossover
sections currently available in mobile audio. They feature third-order 18dB/
octave Butterworth filters. These filter networks sum to a flat response at their
-3dB break points. This results in a smooth and seamless transition from one
frequency band to the next. Butterworth filters provide maximally flat
frequency responses when compared to other filter structures.
All crossover controls are mounted on the top of the amplifier. The internal
subwoofer crossover features a 18dB/octave Lowpass filter and a 18dB/octave
Subsonic filter. The Lowpass Filter is continuously variable from 50Hz to
5kHz and the Highpass from 15Hz to 1.5kHz.
The D7401 amplifier also provide a separate fully-independent crossover for
the output RCA jacks providing filter control of any other amplifier. It is
continuously variable from 50Hz to 5kHz; High, Low, Bandpass or Full Range.
When switched off, they are completely out of the signal path.
13
THERMAL MANAGEMENT SYSTEM
All
D7 Professional Reference Series Amplifiers
feature our
Intelligent Thermal
Management System
. All amplifiers feature one or two (depending
on model) internally mounted temperature-controlled cooling fans.
Care should be taken to allow adequate “breathing room” (approximately
2 inches) on all sides of the installed amplifier to allow the system to operate
at peak efficiency.
Cool outside air is drawn into the amplifier through the side vents on each
end panel. The air is then drawn over the top of the main circuit board, down
through the fan over the internal heat sink fins (in two directions) and out
through exhaust vents on the bottom of each end panel. In this way, the
cooling fan(s) remain nearly inaudible under almost all listening conditions.
When D7 amplifiers operate at high power for prolonged periods, the
temperature sensors instruct an intelligent monitoring circuit to speed up the
fan(s) until the amplifier has cooled down to its normal operating temperature.
Amplifier models D7401 also features our unique Power-Flow Busbar. The
shroud connecting and covering the two internal cooling fans of these amplifiers
is made of solid nickel-plated copper. Each end of this fan shroud is soldered to
full width pads on the main circuit board. The center
of this shroud is attached to the fans at eight points. The high current ground
path for the speakers now travels over the cooling fans through the shroud,
which functions as a busbar. At the same time, these high current signals are
completely isolated from the circuit board traces that carry low-level signals.
