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Rockford Fosgate T400X4ad Power 400 Watt Class-ad 4-Channel Amplifier

  • Based on 111 reviews
Condition: New
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Availability: Only 3 left in stock, order soon!
Fulfilled by Dynamic Autosound

Arrives Thursday, Nov 6
Order within 14 hours and 53 minutes
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Features

  • Our ultra-compact (1.6 x 4.3 x 8.3) Power T400X4ad 4-channel amplifier produces more power per square inch than any other model we make with 400 Watts of POWER
  • Proprietary Constant Power amps are the most powerful on the market, delivering up to 25% more power across all impedance loads (100 Watts x 4 @ 4-Ohm or 100 Watts x 4 @ 2-Ohm or 200 Watts x 2 @ 4-Ohm Bridged)
  • Proprietary Class-AD technology, featuring Constant Power to produce the same output at both 4-Ohm and 2-Ohm, making it perfect for hybrid, electric, small cars, trucks, motorcycles, and side-by-side UTVs
  • High-level auto turn-on, CLEAN circuit input/output clip detection, On-board Punch EQ with +18dB boost @ 45Hz and 12dB/octave Butterworth crossover make T400X4ad an impressive POWER house
  • Famous Rockford Fosgate build quality ensures that the T400X4ad will handle everything you throw at it! Full 2-year parts and labor warranty

Item dimensions L x W x H: 11 x 3 x 6 inches


Voltage: 12 Volts


Manufacturer: Rockford Fosgate


Mounting Type: Boat Mount


Brand: Rockford Fosgate


Item dimensions L x W x H: 11 x 3 x 6 inches


Voltage: 12 Volts


Manufacturer: Rockford Fosgate


Mounting Type: Boat Mount


Brand: Rockford Fosgate


Number of Channels: 4


Output Power: 4E+2 Watts


Package Type Name: box" or "installation kit


Specification Met: Implied 12v Standard Voltage and Potential Compliance With Industry-specific Audio Standards


Material: Electronic component material and epoxy


Global Trade Identification Number: 88


UPC: 780687342388


Product Dimensions: 11 x 3 x 6 inches


Item Weight: 3 pounds


Item model number: T400X4ad


Is Discontinued By Manufacturer: No


Other display features: Wireless


Whats in the box: A Amplifier With Standard Accessories


Date First Available: July 8, 2014


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Thursday, Nov 6

Yes, absolutely! You may return this product for a full refund within 30 days of receiving it.

To initiate a return, please visit our Returns Center.

View our full returns policy here.

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Top Amazon Reviews


  • Rockford always over performs
As every Rockford amp I've ever owned ( more than 20 ) this little giant puts out crazy numbers, has great sound quality and will last, the only knock I have are the connectors, they can be finicky and the RCA's are not of the best quality, which are easily replaced, other than than this little monster will amaze you, something that small using that little current could put out levels like it does. ... show more
Reviewed in the United States on November 20, 2021 by Charles W.

  • High quality, very underrated!
This amp is great! Started with just one, and now I have several of them. When these small Rockfords first came out, they were expensive, maybe $800. Once production ramped up, they dropped to half that. My amps are in a very high end system with ten (10) active channels - eight (8) of which come through two of these amps. Overall, the system is probably a $15,000 stereo, and this amp has all of the quality you’d need to fit right into a system of that caliber. The info lights on the amp let you set the gains to safe levels without using an external device, so installation is fairly easy. Don’t be fooled by the size, it’s a seriously high end amplifier. The reason it’s small isn’t because there’s less amplifier. It’s because the cooling is active, rather than passive (i.e. it has cooling fans). That means the heat doesn’t need to get spread over a large area. Instead, fans just blow heat away, meaning there’s no need for a large heat sink. Basically, the electronics are full scale, and the cooling solution allows a smaller size. The main reason to get this amp over other 4-channel amps is because of the Constant Power circuitry. Basically, it won’t be louder or quieter depending on which impedance load your speakers have. That means you can run 4-ohms to keep your amps cool without losing any noticeable sound volume. Great product! ... show more
Reviewed in the United States on August 12, 2018 by MVDO

  • Awesome amp.
Best amp I have installed yet. Great sound and very powerful.
Reviewed in the United States on July 2, 2019 by Roel Lerma

  • A very good product
It’s a great product I’ve been using it for years the only thing that I see that I have a 98 Harley Davison and they sold me the brackets kit to put it on top of the radio while they do not work so it’s kind of a waste of money on that part because I didn’t use any of it on that I had to Velcro it to the top of the radio but they swore that that bracket would work other than that it’s a great product sounds awesome very happy with the sound ... show more
Reviewed in the United States on February 13, 2020 by thomas

  • Powerful little 4 channel amp
Clean mids and highs. Lots of dynamic headroom. No cons from me.
Reviewed in the United States on April 28, 2020 by Brian M

  • Amazing sound!
I purchased this amp, 4 rockford speakers, wiring kit with heat sink and you need nothing else. It sounds amazing and cruising 75 mph the sound it puts out can still hurt your ears when you crank it up. Amazing.
Reviewed in the United States on June 14, 2019 by Victor

  • Rockford amp for sxs sucks!!
Haven't had this product for a year yet and both channels have fried. Product might be getting cars but I guess not side by sides.
Reviewed in the United States on September 30, 2021 by Jeremy R.

  • Best set up yet for my GL1800
Weaseled this amp into the trunk and a pair of Polk DB 6.5 components in the dash, Sowchrome speakers in the rear. Now I can finally get a taste of bass at 70 mph. The gl1800 is probably one of the most difficult bikes to make any seriously noticeable improvements in audio quality due to horribly small speaker enclosures. Added a couple of small fans to help circulate air even though it has internal fans. Black bike, no ventilation for trunk. After being left out in the parking lot all day in the hot Texas summer sun, the amp is already so hot you can't keep your hand on it. Made it though the entire summer without overheating. Including some 1 hr long freeway runs at high volume. Sound is clear and powerful. I have the gain set at 3/4 and rarely turn the volume up more than half way. If you have a later model wing and want to make a big improvement without sacrificing your saddlebags and truck space, this amp will fit on the side of the trunk using Velcro and the crossover boxes for speakers can fit on the opposite side. This amp is what Honda should have worked into the bike. And as an added bonus, because I removed the factory amp, I no longer have to remove the seat for tire changes. ... show more
Reviewed in the United States on November 27, 2019 by John

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