CEA-2006 Compliant: CEA-2006 is a system of testing and
measurement methods for mobile audio amplifiers. This voluntary standard
advocates a uniform method for measuring an amplifier's RMS power output and
signal-to-noise ratio. The criteria for measuring power uses a DC input voltage
of 14.4 volts and the RMS power output is measured with 1% or less Total
Harmonic Distortion plus noise (THD+N) over a frequency range of 20 Hz to 20 kHz
(for full range amplifiers). Signal-to-Noise ratio is measured in weighted
absolute decibels (dBA) at a reference of 1 watt into 4Ω. CEA-2006 allows
consumers to compare car amplifiers and receivers on an equal basis. Using
CEA-2006 criteria, the Rockford Fosgate P400X4 is rated as follows:
- Power Output:
- 4Ω: 50 watts x 4-channels
- 2Ω: 100 watts x 4-channels
- Bridged: 200 watts x 2-channel (into 4Ω)
- Signal to Noise Ratio: 85 dBA (105 dB at rated power)
Aluminum Heatsink: The cast aluminum heatsink dissipates heat
generated by the amplifier's circuitry. The inherent
advantage of casting provides a 30% cooling improvement over conventional
extrusion heatsink designs.
Dynamic Thermal Management (DTM): DTM evenly distributes
excess heat across the amplifier's entire heatsink.
MEHSA³ (Maximum Efficiency Heat Sink Application-3rd Generation):
MEHSA is a Rockford Fosgate proprietary process that increases the heat transfer from
the MOSFET devices to the heatsink. The multi-layer insulated metal MEHSA substrate
operates with minimal thermal resistance, spreading heat both downward and outward
to quickly dissipate heat from each device across the heatsink. This allows greater
power output, enhanced thermal stability, and maximum reliability.
Trans-ANA (TRANSconductance Active Nodal Amplifier): Trans-ANA
is a circuit that allows the audio signal to pass through the amplifier at low
voltage. The signal is directly level-shifted to the fixed high voltage rails
via a pair of drive transistors. Signal linearity is assured by an active node
formed by the drive transistors at ultrasonic frequencies. The result is crystal
clear sound quality.
NOMAD (NOn-Multiplying Advanced Decision): NOMAD is an intelligent
protection circuit that uses an analog computer to make real time decisions regarding
temperature, voltage, current and impedance. The amplifier is protected without
limiting sound output unless needed.
DSM (Discrete Surface Mount): High speed robotics are used in
the manufacturing process to place 1% tolerance parts and large board traces. DSM
improves the efficiency of the circuit, decreases cross-talk from other discrete
components and lowers operating temperature.
CLEAN Set-Up: Rockford's integrated level setting technology,
CLEAN (Calibrated Level Eliminates Audible Noise), replaces sophisticated test
equipment with input/output clip LEDs, allowing you to match the source unit's
output to the amp's gain, and optimize the amp's output. The input clip indicator
works in conjunction with the audio source volume, illuminating red when the source
reaches it's clipping point. The output clip indicator works in conjunction with
the input level dial on the amp, illuminating the appropriate color depending on
the audio content used for the setup.
Power and Protection LEDs: The LEDs are located on top of
the amplifier. A blue Power LED illuminates when the amplifier is turned on. A
red Thermal LED illuminates if the amplifier overheats. The yellow Protect LED
illuminates if a short circuit or too low an impedance is detected at the speaker
connections. When any of the protection circuits engage, the amp automatically
shuts down until the problem is corrected.
Balanced Differential Inputs: Differential inputs eliminate
noise picked up by signal cables by measuring the voltage of both the (+) and (-)
input signal, then subtracting the voltage common to both conductors (noise),
resulting in only the clean signal entering the amplifier.
Input Level: The front and rear sections of the amplifier
have separate input level controls. To accommodate the varying range of signal levels
from today's factory and aftermarket radios, the input levels are adjustable from 150mV
Crossover: The amplifier's internal crossovers are also
independent for the front and rear channels. The slope is 12 dB/octave and
both can be set to high-pass, all-pass (full range), or low-pass operation.
The crossover points are variable from 50 Hz to 250 Hz.
Punch EQ: Both the front and rear amplifier sections have
Punch EQ circuits, the function of which changes with the crossover switch. When
the crossover is set to low-pass, the Punch EQ acts as a variable bass boost; 0-18
dB at 45 Hz. When the crossover is set to high-pass, the Punch EQ acts as variable
treble boost, 0-14 dB at 12.5 kHz. When the crossover is set to all-pass, both the
bass and treble boost circuits are active.
Input Switch: With the input switch in the 2-channel position,
connecting only the front inputs will send the signal to both the front and rear
sections of the amplifier. In the 4-channel position, both front and rear inputs
must be used.
Power Connections: The power and ground terminals are nickel-plated
captive c-clamp wire connectors and will accommodate up to 4-gauge wire. An external
60-amp fuse (not included) must be installed on the power wire. The remote turn-on
terminal will accept up to 12-gauge wire. A Phillips or flat-head screwdriver (not
supplied) is required to tighten/loosen the terminals.
Speaker Connections: The four pair of speaker output terminals
are also nickel-plated captive c-clamps and will accept up to 8-gauge wire. A
Phillips or flat-head screwdriver (not supplied) is required to tighten/loosen
Signal Input: The front and rear RCA inputs will accept either
a line-level or speaker-level input. A speaker-level signal can be connected using
a Speaker Wire to RCA adapter (sold separately). When using a speaker-level input
signal, the auto turn-on feature is active and the remote turn-on terminal becomes
a 12 volt output to turn on/off up to two additional amplifiers or other components.