Summary: This is truly an amazing amp. I have it hooked into a Kenwood 6190HD head unit and "stock" Dynaudio speakers. You have to give it time to break in. But when it does, it sings. The control is amazing. Imaging is fantastic. Voices and instruments hang in the air like they would in a high-end home audio system. I like road trips now, because I get to listen to my music on this gear. Very pleased.
Pros: Amazing sound and control. Not too large. Runs pretty cool.
Summary: started off with the hd1200/1 for my 13.5W7AE. blew me away, then i decided to buy this amp for my CDT HD series speakers. what an amazing difference this amp made in my vehicle. after putting this amp in you can clearly tell that my speakers are getting super clean power. setup is a breeze, amp is small, and 150 watts x4 RMS is plenty. the clarity is unbelievable with my EQ settings "Flat.
Pros: small amp, efficient, clean power
Cons: this amp doesnt have a built in HD tuner (i kno that makes no sense but i had to put something in this dialogue box) :)
Summary: First off this footprint is an ideal size and that's it ! I've been wanting to try this amp for awhile to complete my Jl set setup...HU alpine iva w205, Jl zr650csi, Jl tr650 all wiring Jl..its not what I expected at all for $$$$$ period I'm putting my polk pa660 right back in it seems even at 75 rms was warmer in sound and pushed the setup beyond it needed vs the HD and the gain isn't even 3/4.
Pros: Size, size, size
Cons: Better amps out there for less $$$$ your buying the name in this case...
Conclusion: I dont personally run this amp, but a close friend of mine does whom ive helped install/tune his system. The size of the amp is pretty small, so you have more options for amp placement. This is a powerhouse to, and sounds great. The only complaint, is that it uses a connecter for the speaker terminals instead of wiring directly to the amp (this is me personally, its a lot easier for isntall purposes and you dont run the risk of stripping out the phillips screws on most...
Summary: Acabo de recibir mi jl audio hd 600/4 y estoy un poco desepcionado, lo compre por que pense que sonaria mejor que mi alpine pdx 4.150 , pensando que el jl hd seria mejor, pero no fue asi, el hd tiene unos agudos un poco chillones , el pdx es bastante calido ,los ajustes y ganancias practicamente estan igual. sinceramente no valio la pena gastar 800 dlls cuando puedes comprar un alpine pdx 4.150, mi hu es una alpine cda-117,mis bocinas son dls iridium 6.3 3 way .
Conclusion: I decided to get serious with my new car and the audio system and did a hell of a lot of research and it certainly paid off. This is the best amp I have ever had, and may I say I've been a DJ for 26 years and this JL HD600/4 amp can handle anything! Combined with JL C5650 Audio speakers and a 12" sub, the sound for me is just superlative with so much headroom and zero distortion. Thanks also to Sonic Electronix for such a great deal.