The D3 Series Amplifiers provide a wide range of power and features that make them an
excellent choice for a variety of car audio sound system configurations.
D3 Amplifiers use an unregulated power supply for good control of output power. This
power supply design helps yield maximum power transfer with a minimum of heat loss.
On board noise filtration is used to keep unwanted noise from leaking into the system from the
amplifier. Each D3 amplifier comes complete with thermal, short, and load protection circuits
as well.
INTRODUCTION
The Diamond Audio D3 Series Amplifiers incorporate the following features:
Full frequency response with low distortion and exceptional signal to noise performance.
Advanced circuit design that features stereo, mono and mixed mode operation for use in a
variety of systems.
Variable high-pass/low-pass electronic crossover with a 12 dB per octave slope and fully
adjustable range (55 Hz~550 Hz).
Variable bass boost circuit to reinforce low frequency signals.
Adjustable input level controls with ground loop isolation accepting a wide range of input
signals.
Remote turn-on with "soft start" muting to prevent turn on "thump" .
Pulse-width modulated (PWM) MOSFET power supply with low AM RFI and protection
circuits for overheating and speaker shorts.
Nickel-plated input/output connectors and an external automotive type fuse.
Aluminum heat sink for efficient heat dissipation.
Low profile, compact size for space limited installs
TABLE OF CONTENTS
Description
Specifications
Power and Speaker Connections
Input Connections and Audio Control
Setting the Gain
Setting the Crossover
Setting the Bass Boost
Troubleshooting
System Diagrams
DESCRIPTION
1
2
The following figures show the power/output end panels for each amplifier along with a key
to show the layout of each amp.
All connections and controls for the D3 Amplifiers are located on the end panels.
Plated connections ensure excellent conductivity and good looks. Easy to understand controls
make setting the amplifier up correctly an easy task.
SPECIFICATIONS
4 Ohm Stereo Output
2 Ohm Stereo Output
4 Ohm Mono Output
Frequency Response
Signal-to-Noise Ratio
THD
Input Sensitivity
High Level Input Sensitivity
Power Supply Operating Range
Dimensions
POWER AND SPEAKER CONNECTIONS
Fig.1 D3 400.2
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2
3
4
5
6
1.Left Speaker Output
2.Right Front Speaker Output
3.Remote turn-on lnput
4.Ground lnput
5.12v lnput
6.40 Amp Fuse
Fig.2 D3 400.4
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2
3
4
5
6
7
8
1.Left Front Speaker Output
2.Right Front Speaker Output
3.Remote Turn-on lnput
4.Ground lnput
5.12v lnput
6.40 Amp Fuse
7.Left Rear Speaker Output
8.Right Reart Speaker Output
132w@1%THD
210w@1%THD
420w@1%THD
20Hz~20KHz
>100dB
.05%
250mV~2.5V
500mV~5V
10.8V~15.6V
2 1/4" H x 8 1/2" W x 12" L
57w@1%THD
88w@1%THD
182w@1%THD
20Hz~20KHz
>100dB
.05%
250mV~2.5V
500mV~5V
10.8V~15.6V
2 1/4" H x 8 1/2" W x 13" L
D3 400.2
D3 400.4
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2
2
3
4
4
4
4
5
