i have a rockford fosgate 400.2 amp and the gain input goes from 150mv to 5 volts, is the 5 volts with the gain all the way down or up? when i was setting my gain with a 60 hz 0 db test tone yesterday mine only reads 1.6 ac volts on the dmm at volume 22 of 30 (volume 23 it clips) and on the gain there is voltage marks and it's near the 3 mark, plus i can't turn my head unit any higher or it clips, then i noticed the bass sounded cleaner, but not even loud, before i used to have the gain 3/4 the way but idk if i was clippin it or not, i don't get this do i need a new head unit with better preouts? or are my ears really unsensitive to bass? thanks for the help.
Almost all HUs clip/distort around 85% mark on the volume setting. What you need to find out is what your pre output voltage is on the HU. Match that with the amp. Usually the 150mv is on the right and 5v or the max is on the left. Your owner's manual will tell you exactly how it's set. From your description, it sounds like your HU is 2v out. Don't go past the clippign point, or else you will risk blowing your sub as well as the amp. If you assume the 150mv is on the right, then the gain/level should be half way or a bit to the right. Try that and see.
so i looked in my HU's manual and it said 2.2v max and that's max volume on the HU with EQ FLAT. I even checked with a dmm and it read that with a 60 hz 0 db tone to make sure. ok so my gain on my amp has these markings by it, all the way on minimum it says "1" then all the way up it says "11" so i should put it in between the "1" and "3" mark on the gain, would that work too, i hope the output is enough to push my l5 cuz on "1" it doesn't even move.
If your gain goes from 1 to 11, then somewhere between 5 and 4 should equal to 2v. Just what kind of sub do you have? Is it DVC or SVC? Is the amp bridged or is it powering each VC(if it's DVC). Is the amp class D or AB? If it's AB, is it set for sub? Look for frequency cut off.
ok. kicker solobaric 12" L5, yes it's DVC, amp is bridged, have it wired for 4 ohms, didn't want to wire it for 1 ohm. amp is class AB, yeah, i have it on LPF. The frequency cut off for the crossover on the amp is 12 db/octave.
Okay, you might have to test the amp separately. Hook up a full range speaker on the amp, pick ch1 or ch2, doesn't matter, connect the amp to the HU or a portable cd player, set the gain/level, turn up the volume and see if you get music. Test with low, med, and high volume setting. If everything works, then the problem with your sub lies somewhere in the bass/frequency setting. Something is cutting off the lows to the subs. Double check your settings on the amp.
you were right on havin the gain near the 5, i hit the 20 v with the left channel and didn't get the 40v till i had my HU on max volume, i'm beginnin to think this amp won't do 400 rms bridged without bein clipped to hell.