Rockford Fosgate P400-4 400 Watt 4-Channel Amplifier

From the Manufacturer

From the Manufacturer

Manufacturer's Description (November 1, 2008)

If you're considering a new car audio system or just want to upgrade your current system, Rockford Fosgate equipment is a solid foundation on which to build. Rockford is one of the oldest and most respected brands in car audio history, and has been pumping out high quality, great-sounding gear since 1973. By pioneering ideas like the Punch EQ (boosting frequencies below 45Hz and above 20Khz for improved in-car music response) and using MOSFET circuitry to power in-car amplifiers, Rockford Fosgate paved the way for modern in-car electronics and hasn't slowed down since.

The P400-4 features an ultra-small small footprint, and a clean, simple design that looks great no matter where it's installed.

Dynamic Thermal Management ensures even heat dissipation across the entire heatsink for maximum efficiency and cooling.

Rockford Fosgate amplifiers combine raw, clean power, with sleek, smart designs that are easy to install and look great in any car. All Rockford amps are CES-2006 compliant, which means the power listed is the actual power delivered, and each amp includes a birth certificate to prove it. But don't let the small size fool you; this petite powerhouse, which can easily fit under any seat, packs quite a punch! The P400-4 is the perfect companion for two pairs of coaxial or component speakers, or a pair of speakers and a simple subwoofer system. The P400-4 delivers 50 watts of clean power to for channels in stereo mode, or 200 watts per channel when bridged down to a two channel amp. But what exactly sets a Rockford Fosgate amplifier apart from the competition? Plenty.

Keeping Things Clean and Cool
The amplifier's job is to produce power, and lots of it. But a side effect of creating power is heat, and that is an electronic component's worst enemy. Rockford tackles this problem by incorporating a cast aluminum heat sink, Dynamic Thermal Management, and MEHSA³ technology to every amplifier, resulting in a significant reduction of the amplifier's operating temperature. The cast aluminum heat sink surrounds three of the four sides of the amplifier's circuit board, which maximizes the cooling surface area, and since the heat sink is cast it offers 30% better cooling ability over extruded designs. When combined with Rockford's patented Dynamic Thermal Management (DTM), cooling efficiency is taken one step further. DTM distributes heat evenly across the heat sink where other heat sink designs can create dangerous hot spots in the amplifier. Rockford also developed MEHSA³ technology for the MOSFET (metal–oxide–semiconductor field-effect transistor) power transistors. MEHSA³ (Maximum Efficiency Heat Sink Application- Third Generation) maximizes heat transfer from the MOSFETs to the heat sink for up to five times better heat transfer. By keeping the internal components cool, the amplifier maximizes efficiency, produces more power, and reduces distortion for increased sound quality.

Not only does the P400-4 produce lots of clean power, it also delivers exceptional sound quality. Differential input circuitry measures the positive and negative input signal as it enters the amp and subtracts the voltage common to both conductors (noise), resulting in a crisp, clean signal for maximum sound quality. The use of TRANS-ana circuitry, borrowed from pro-audio company, Hafler, also adds to the sound quality recipe. The TRANS-ana circuit simplifies the audio signal and allows it to travel through the amplifier as a low voltage signal before it reaches the amplification stage. This improves the sound quality of the signal, delivers cleaner performance, and improved reliability.

The P400-4's TO-247 MOSFET power transistors offer 60% more metal tab area than the industry standard TO-220 MOSFETs, which means more power, better cooling, and improved sound quality.

Once the signal reaches the amplification stage, it's greeted by much beefier MOSFETs than what is traditionally used in most amplifiers. Rockford uses TO-247 MOSFETs compared to the somewhat standard and less efficient TO-220 MOSFETs. TO-247s offer 60% more metal tab area, which means more power capacity, better heat dissipation, and lower impedance capability. In other words, these things produce some serious power with very little effort.

The Punch EQ can be tweaked to deliver up to an 18dB increase at 45Hz for subwoofers, or up to a 12dB increase at 12kHz for speakers. This improves overall sound quality and overcomes audio response problems common to the automotive environment.

Rockford Fosgate built a reputation around the Punch EQ, which is incorporated into their Punch amplifiers, and allows the amp to better shape the sound quality of your speaker or subwoofer system. When using the high-pass crossover, the Punch EQ can boost high frequencies above 12kHz anywhere from 0-12dB. This frequency range is often lost to road noise and other factors, and the Punch EQ allows you to dial up that range for perfect sound. If the low-pass filter is on, the Punch EQ can add a bit of boost (up to 18dB) to the 45Hz frequency range. This gives you the ability to dial in a little extra rib-rattling bass to your music that can be lost due to the compact size of most car interiors.

Making the Connection
All controls and connections are located on one edge of the amplifier, making it easy to access all controls and guaranteeing an easy, clutter-free installation. The P400-4 will accept up to 4-gauge power and ground wire, and all connections are neatly housed in c-clamp type connectors that terminate inside the amp's chassis. This adds a cleaner appearance to your install and ensures no \"fly-away\" wires can stray to other terminals causing possible shorts.

All connections are recessed into the amplifier's chassis and located on the bottom edge of the P400-4, for a clean, uncluttered install that looks great in any car.

Speaker connections also use a similar clean audiophile design, and will accept up to 12-gauge wire for maximum signal transfer to your speakers or subs. The amp features a single RCA connection flush with the amp's chassis, further enhancing the overall clean appearance.

An RJ-45 jack is for connecting an optional remote-mounted Punch EQ control and is located next to the crossover and Punch EQ controls. The remote PEQ controller can be installed up front and within easy reach to give you on-the-fly control of your Punch EQ settings.

Pushing Power
The P400-4 is a flexible amplifier and is stable at two-ohms. This amp is perfect for powering front and rear speakers in four-channel mode, delivering 50 watts of clean power to each speaker. Or you can mix things up a bit and use the P400-4 to drive two front coaxial or component speakers at 50 watts RMS and bridge the rear channel to deliver 200 watts to a subwoofer.

What’s in the Box
P400-4 amplifier, Installation & operation manual, Warranty