Summary: I needed a new amp for my car and i love JL products . Im convinced this is a JL outside with counterfit internal components because of the static lact of clarity. My 240 watt alpine sounds much better than this 400 watt "JL". Only 3/4 of the channels worked.
Summary: The XD400/4 is my fourth 4-channel amp to grace my cars throughout the years. I am running a Pioneer DVD head unit, through the JL amp into Focal Access components in an Audi S4. After ~5 weeks of burn-in, tweaking, tuning, etc, I still could not achieve a sound with which I was satisfied. My reference material (Dire Straits/Brothers in Arms SACD, Nils Lofgren/Acoustic Live, Elton John/(various SACDs) lacks the dynamic punch I've had with every other system.
Pros: Form factor/size, solid construction, tight bass control
Cons: Lacks dynamics, disappointing upper frequencies, listener fatigue on long trips
Summary: First of all i do not write reviews at all, i dont think i am good at it but i bought this thing to run my mids and highs and got a 500/1v2 to run my pioneer 12" 1000rms sub and boy dose this work, my set up was not professionaly installed so the 500/1v2 got fried duty to lack of experience by my friends, so i decided to use my XD400/4 to run mids and bass and boy dose this thing work, i had to brige it to get enought power to the sub aprox 150rms and i also bridged...
Summary: OK, when i first saw this amp on the website i was looking for a 4 Channel that would not take up the whole trunk. Once I installed it & did my fine tuning, i was truly impressed,and it's so small that friends ask me WHERE IS THE AMP!! I have it running a 6 inch in the doors & 6 by 9. Upgrade coming soon. Thanks Crutchfield.
Pros: Small footprint,easy to set up,and the power nice and clean. Not amp pop went comes on are powers off.
Summary: I have a 2001 Mustang convertible. I had to find an amp theat would fit behind the rear seat. This was that amp... I completely tore out the stock sound system (Mach 460). I paired this amp with a Pioneer AVH-P2400BT. For speakers; JL Audio C5 570's in the front and C3 600's in the rear. I still cannot believe how awesome my system sounds! Running 70 mph down the highway with the top down is no longer an issue!
Pros: SIZE, Easy to Instal, SIZE, very powerful unit
Summary: I really liked my setup with this amplifier but after 2 years it started to give me trouble. It was suggested by Crutchfield to replace the speaker but that didn't fix the problem and the installer told me to look into a new amplifier. I didn't think that this was a trial and error fix. Now my right rear subwoofer and speaker cut out when I start up the car.
Pros: It has as nice sleek design that looks neat and tidy. There are many features that are adjustable. The wiring setup makes changing connections easily accessible.
Cons: The amp really needs to have a ventilation/heat exchanger setup.
Summary: First off this is the first time I've ever installed an amplifier, and while the thought of drilling holes and running all those wires was intimidating I'm really glad I did it. It was easily installed under the passenger seat of my Subaru Forester with lots of room to spare. The end result is worth it, my music is noise free and this can really push a set of high end speakers to the limits... OMG can this thing get loud!
Pros: Zero noise, minuscule footprint compared to other amps with similar wattage, no heat buildup at all.