2001 jeep TJ
Crutchfield Customer Review (What's this?)
Very satisfied Good upgrade for my system
Pros: Easy install and setup
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Item #: 575P400X4
$269.99 Earn up to 270 Rewards points
Rockford Fosgate's Punch P400X4 amplifier can put out 50 watts RMS to each of your front and rear speakers, plenty of power for clean music even at high levels. You can use the amp's high-pass filter to remove low bass from your speakers so they'll play more efficiently. You can also switch this amp into 2-channel mode to drive a couple of subwoofers with up to 200 watts RMS each. The amp's low-pass filter comes in handy for getting the right sound from your sub/enclosure combo. The Punch EQ2 includes bass and treble boosts, in case you want to add some boom and sizzle back into the mix.
P300X2 control panel shown as example
Once again, Rockford Fosgate steps away from the crowd with their C.L.E.A.N. technology (Calibrated Level Eliminates Audible Noise) — a setup system that ensures your music will sound as clean and powerful as possible. It works like this: play the setup tone on the included test CD, adjust the receiver volume until a red clip light on the amp goes out, then turn the amp gain up until a blue light comes on. It's that simple — your amplifier is now set to match your receiver's output. When your receiver reaches maximum clean volume, you'll get maximum clean power from your Punch amp. At quiet listening levels, you'll hear less background noise and more of your music.
If that blue light turns solid red while you're playing music, the amp's telling you that your source is distorting and you should turn it down, or risk damage to your gear. The amp's built-in computer keeps tabs on the output current, ensuring that plunging speaker impedances (they change during play) or even a short circuit won't hurt anything.
Rockford Fosgate's Dynamic Thermal Management system uses forced air to dissipate heat evenly across the amp and out through the high-mass heatsink, efficiently drawing heat away from vital internal parts. Their proprietary MEHSA cooling process maximizes the heat transfer from the MOSFET devices to the heatsink, allowing the heat to escape more readily, so the transistors stay cooler and work better.
P400X4 connection panel and input clip light
Very satisfied Good upgrade for my system
Stuart, Nashville, TN
Very satisfied Good upgrade for my system
Pros: Easy install and setup
It has been years since I have upgraded a car stereo but I have always been loyal to Rockford Fosgate. This amp is the perfect amplifier for those that are looking to take their factory stereo to the next level. I was really surprised at just how much more power this amp puts out over the factory head unit. I used to turn my stereo up to 20 before I could hear it clearly. Now I can hear it clearly at volume level 6. Hats off to RF for making excellent products.
Pros: Adds clean undistorted power loud built in crossovers
Cons: None yet
I can't believe I thought powering my speakers through the Pioneer head-unit sounded good. This Rockford Fosgate amp is a revelation. Not so much in loudness but in liveness and immersive sound. I run it through Focal Integration speakers, which had a "colored" sound when powered by the head-unit. Through this R-F amp the Focals have clarity and vehicle-filling sound. I think this amp and speaker combination adds to the liveness effect, given that Focals have a reputation for "revealing" sound. Recordings I have heard for years have a fresh perspective, especially over HD radio.
Pros: The featured Trans-ANA circuitry is a deal-maker.
Cons: I think a bypass switch for the punchEQ and crossover circuitry would be nice. I'm a flat-EQ listener and also the Focals are pretty punchy already.
Good amp for the money.
Installed this amp to power my component speakers. 2-6x9's and 2-6 3/4" speakers. Super easy to install, and the SMART no clipping is really easy to setup. Sits very nicely under my passenger seat.
Pros: Super easy setup, enough power for component speakers. Sounds AMAZING!
Cons: Using the SMART clipping setup, i felt the speakers were a bit under powered. I increased gain a bit above their recommended level and now it sounds good.
bought the p400x4 to power a set of p1675 components for the front and a set of p16 coax in the rear. it works great in my set up and the c.l.e.a.n. system makes it easy to set the gains
Pros: good for the money
Cons: none so far
I got this amp on sale. At that price point it is a truly excellent performer. Musically solid with very little coloration and decent power for a nice set of components in the front and co-ax in the rear.
Pros: - High performance for the price - Good power and clarity
Cons: - At this price point I really can't complain. It certainly isn't a high-end 4-channel amp, but it performs at a good mid-level for a good sale price.
Works very well, I love the auto setup of tuning it so yur speakers aren't clipping or getting any distortion and I personally think that there putting out a lot more power than 50rms id say more like 75 80 great amplifier
|RMS Power Output (Watts x Channels)||
50 x 4
|Peak Power Output (Watts x Channels)||N/A|
|Power at 2 Ohms (Watts x Channels)||100 x 4|
|Bridged Power (Watts x Channels)||200 x 2|
|Minimum Impedance Bridged||4|
|Minimum Impedance Unbridged||2|
|Best Frequency Response||20-20k Hz|
|THD at Rated RMS Power||1%|
|Signal to Noise Ratio||85 dB|
|Low-Pass Crossover Frequency||50-250 Hz|
|Low-Pass Slope (dB/octave)||12 dB/octave|
|High-Pass Crossover Frequency||50-250 Hz|
|High-Pass Slope (dB/octave)||12 dB|
|Bass Boost||0-18 dB|
|Bass Boost Frequency||45 Hz|
|Speaker Level Inputs||RCA|
|Parts Warranty||1 Year|
|Labor Warranty||1 Year|
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:
Cast 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 to 12V.
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 the terminals.
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.
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Rockford Fosgate's C.L.E.A.N. gain-setting system on their Punch amps makes setup as easy as playing an audio track and adjusting a couple volume knobs.
I have had it before and it is a great amp. [ Joseph May 22, 2016 ]
Size and features. The anti clip set up is a nice feature. [ MICHAEL Feb 05, 2016 ]
Rockford Fosgate has a reputation for consistent quality and excellent power output. There latest amps do not disappoint. [ Chance Dec 26, 2015 ]
I would recommend the p600x4 to get the most out of the speakers. The p400x4 would work too just wouldn't be as loud or hard hitting as the 600. [ TREVOR Feb 18, 2015 ]
I like mine. Has plenty of power. I don't have a subwoofer. [ Bobby Feb 17, 2015 ]
I replaced factory speakers. I can't compare them to yours but I like them. Just remember that the Twitters are separate and have to be mounted separately. [ Bobby Feb 17, 2015 ]
no. it does not [ RICHARD Jun 22, 2014 ]
No it doesnt [ BRIAN Jun 17, 2014 ]
Yeah, you can. But honestly I would just go buy the P300X2, and a mono block for your sub. Bridging for the sub on this amp will only give you like 250 watts rms to your sub. And that's like...max. Also I'm not entirely sure if you can make 2 channels high pass, and the other 2 low pass. Just be sure you buy a 2 ohm DVC sub if you're going to bridge it. [ Luke May 24, 2014 ]
All of our products display the RMS power ratings. This provides a more real world ideal of the power you will get from the unit and avoids the numbers game that gets played with Peak power. You can find some good tips on choosing speakers here: http://www.crutchfield.com/learn/blogs/av_tips/archive/2007/05/31/car-speaker-tips.aspx?showAll=N [ Jeff Feb 08, 2014 ] Staff