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

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.

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!

Best amp I have installed yet. Great sound and very powerful.

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

Clean mids and highs. Lots of dynamic headroom. No cons from me.

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.

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.

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.