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Rockford Fosgate Power T800-4AD
4-channel car amplifier 150 watts RMS x 4
Item # 575T8004AD | MFR # T800-4AD
This item is no longer available.
Our take on the Rockford Fosgate Power T800-4AD by Crutchfield's Buck Pomerantz
Rockford Fosgate's Power Series Amplifiers
Rockford Fosgate has a well-deserved reputation for building high-quality mobile audio products. Their Power Series amps occupy the top of the amplifier food chain, with fine-tuned audio controls, extreme durability, and proprietary technologies that deliver stronger, more reliable performance than most other amplifiers on the market today.
The Power Series T800-4ad 4-channel amp delivers 150 watts per channel into 2 to 4 ohms, plenty enough to get maximum performance from your high-quality speakers or components. The T800-4ad can drive loads as low as one ohm, which is handy for multiple-speaker systems. Or you can bridge your T800-4ad to blast up to 400 watts per channel to a pair of subwoofers. Either way, you can depend on plenty of extremely clean, powerful sound from this Power Series amp.
Rockford Fosgate's high-tech solutions yield more power
Power Series amplifiers actively monitor their speakers' performance using Rockford Fosgate's Constant Power technology. A speaker's impedance naturally fluctuates as it performs. So, just like your cruise control increases the engine's RPM to maintain your car's speed uphill, Constant Power circuitry maintains this amp's output by increasing its internal voltage and current when the speaker's impedance rises. This results in up to a 25% increase in the amp's total power output.
Rockford Fosgate combined analog and switching technologies (Class AD) to produce this highly efficient, full-range amplifier that has very low distortion. It's also stable down to one-ohm per channel, so you can be sure even low-impedance speaker systems will play safely, as well as loudly.
Dynamic Thermal Management
Power Series amps use Rockford Fosgate's patented, award-winning "Dynamic Thermal Management," a 3-stage cooling system that uses forced air to dissipate heat evenly across the amp and out through the large heatsinks. This results in cooler internal components, higher efficiency, and lower distortion.
MEHSA is a Rockford Fosgate proprietary process that increases the heat transfer from the output transistors to the heatsink. This allows the heat to escape more readily from the amplifier, so that the transistors stay cooler.
"Differential Input" circuitry helps eliminate any electronically induced noise or hum that could be picked up by the input cables, allowing only clean signals to enter the amplifier. You get more music with less heat and noise in a stylish package that's up to 40% smaller than previous models.
What's in the Box:
- 4-channel amplifier
- Four 1-1/2" Self-tapping screws
- Installation & Operation manual (English/ French/ Spanish/ German/ Italian)
- Amplifier Performance Verification Certificate
- 4-channel car amplifier
- 150 watts RMS x 4 at 2 to 4 ohms (200 watts RMS x 4 at 1 ohm)
- 300 watts RMS x 2 bridged output at 4 ohms (400 watts RMS x 2 bridged output at 2 ohms)
- CEA-2006 compliant
- Dynamic Thermal Management cooling system
- Differential Input circuitry eliminates hum
- variable high- and low-pass filters (50-500 Hz, 24 dB/octave)
- variable bass/treble boost (0-18 dB at 45 Hz, 0-12 dB at 12,000 Hz)
- optional remote bass/treble boost
- Class-AD amplifier design with Constant Power
- preamp inputs
- 4-gauge power and ground leads and a 100-amp fuse recommended wiring and hardware not included with amplifier
- no onboard fuses when installing multiple amps in a system, an additional 100-amp in-line fuse between the distribution block and the amplifier is recommended
- 13-9/16"W x 2-1/4"H x 8-1/8"D
- warranty: 2 years
- Our 60-day money-back guarantee
Features and Specs
|RMS Power Output (Watts x Channels)||
150 x 4
|Peak Power Output (Watts x Channels)||N/A|
|Power at 2 Ohms (Watts x Channels)||150 x 4|
|Bridged Power (Watts x Channels)||300 x 2|
|Minimum Impedance Bridged||2|
|Minimum Impedance Unbridged||1|
|Best Frequency Response||20-20000 Hz|
|THD at Rated RMS Power||1%|
|Signal to Noise Ratio||75 dB|
|Low-Pass Crossover Frequency||50-500 Hz|
|Low-Pass Slope (dB/octave)||24 dB/oct|
|High-Pass Crossover Frequency||50-500 Hz|
|High-Pass Slope (dB/octave)||24 dB/oct|
|Bass Boost||0-18 dB|
|Bass Boost Frequency||45 Hz|
|Speaker Level Inputs||No|
|Parts Warranty||2 Years|
|Labor Warranty||2 Years|
Class A/D: The T800-4ad is a Class A/D amplifier, using dynamic switching frequency control to combine the sound quality characteristics of Class-A with the efficiency of Class-D. This technology allows the amplifier to produce more power with less current draw from the vehicle charging system.
Constant Power: The amp is 1Ω stable and the power output doesn't vary much with impedance:
- 4Ω: 150 watts RMS x 4
- 2Ω: 150 watts RMS x 4
- 1Ω: 200 watts RMS x 4
- 4Ω: 300 watts RMS x 2
- 2Ω: 400 watts RMS x 2
Differential Inputs: Differential input circuitry measures the voltage of both the positive and negative sides of the input signal, then subtracts the voltage common to both conductors (noise), resulting in only the original signal. This allows only clean signal to enter the amplifier.
Cast Aluminum Heatsink: The cast aluminum heatsink dissipates heat generated by the amplifier's circuitry. The inherent advantage of casting provides a 30% improvement of cooling over conventional extrusion heatsink designs.
Dynamic Thermal Management (DTM): DTM Evenly distributes excess heat across entire amplifier heatsink.
MEHSA³: MEHSA³ (Maximum Efficiency Heat Sink Application-Third Generation) 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.
NOMAD: NOMAD (NOn-Multiplying Advanced Decision) is an intelligent protection circuit that uses an analog computer to make real time decisions regarding temperature, voltage, current and impedance. The unit is protected without limiting sound output unless needed.
DSM (Discrete Surface Mount): In the manufacturing process high speed robotics are used 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.
Power and Protection LEDs: The LEDs are located on top of the amplifier. A blue Power LED illuminates when the amplifier is on. A red Thermal LED will 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.
Gain Control: The amplifier has independent gain controls for the front and rear amplifier sections, each is continuously variable from 150mV to 5V.
Crossovers: The amplifier's internal front and rear crossovers have independent controls; each can be set to high-pass, all-pass (full range), or low-pass. The crossover point is continuously variable from 50-500 Hz and the slope is 24 dB/octave.
Punch EQ: Punch EQ works along with the crossover switches, and like the crossovers there are independent front and rear Punch EQs dials. When the crossover is set to low-pass, 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, 0-12 dB at 12 kHz. When the crossover is set to all-pass, both the bass and treble boost circuits are active.
2/4-Channel Switch: The 2/4-channel switch changes the T800-4 between 4-channel and 2-channel input mode. When operating in the 2-channel mode, the amplifier produces 4-channels of output with connections to only the front channel inputs.
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 100-amp fuse (not included) must be installed on the power wire. If a wiring kit is used that includes a fuse with a value other than 100-amps, that fuse should be replaced with a 100-amp fuse. The remote turn-on terminal is also a captive c-clamp and will accept wire sizes of 12- to 24-gauge. A Phillips-head or slotted screwdriver (not supplied) is required to tighten/loosen the terminals.
Speaker Connections: The 4-channel nickel plated clamp wire connectors will accept 8-gauge to 18-gauge wire. A Phillips-head or slotted screwdriver (not supplied) is required to tighten/loosen the terminals.
RCA Input Jacks: The front and rear RCA input jacks are nickel-plated to resist signal degradation caused by corrosion.
Remote Punch EQ (PEQ): An RJ-45 jack is provided for connecting an optional wired remote PEQ control (item number 575ROCKPEQ). If you use the remote PEQ, the rear Punch EQ control on the amp is disabled, and replaced by the remote.
Note: Previous model (prior to 2007) Punch Bass and Para-Punch remotes will not work with this amp.
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