My jh1200 2400watts sounds great with the car off but when i start the car it jumps in an out everytime the bass hit it goes to protect an iv tried several differant radios, iv changed rca jacks everthing battery wire remote wire speakers is this a comon problem with this amp

SOURCE: feedback/maxing out speakers.....

its connected directly to the head unit

SOURCE: Audiobahn A 18001DT

the remote of amp. is not a ground it is a pos.+ 12 vlts look the back of your car stereo red the remote and conect to remote of the amp. if no sign remote of the car stereo conect to the 12 vlts of your bat.

SOURCE: THUNDER 5601 WHEN VEHICLE TURNED ON, SUBS BOOM, THEN WORKS OK. ALSO WHEN RADIO TURNED OFF

If the amp produces no boom with no signal input cables connected, I'd suggest using an LOC.

Let me know if you have any other questions.

SOURCE: my mtx thunder 1501d car amp making noise in the subwoofers

This is common with pioneer head units, the rca jacks are not properly grounded and this lets engine noise come through the rcs cables. This thread explains a fix http://www.caraudio.com/forum/showthread.php?t=337644.

SOURCE: i have a mtx thunder 1501d..i have the power cord

Hello tonytone54, The ground should go directly to the vehicle frame, never through a cap, fuse, or anything else. Also, if you are connecting positive through a cap, make sure that you charge the cap before connecting it. Hope this helps.