help with amp

[rich_1989]

got a problem with my system,

brought a vibe 1200w slick sub with a alpine 700w amp with 350 normal running.

not a toal ICE noob as this is my third system install and others were easy how ever they wer standard jobs including RCAs to th back of the HU etc,
wher as this was different. first off i had to splice into the rear speakers and put the wires into some converter (cnt remember what its called)
which converts to RCA plugs, all my wiring is spot on. had to splice into remote cable in back of head unit as im using standard HU (YE YE i kno its not as good as aftermarket HU but looks flush with dash and is the 4x40)

all power and earth are fine. now heres my problem...
when runing the sub it sounds good on some cds and not on others. both running the same kind of music etc, for instance cd 1 is electro house, base is poor, cd 2 is gatecrasher anthems and base is good, when i tune it for one cd the next cd is too loud!
now i am a noob at tuing amps to be honest. i dont know how the LPF works! gain im not too sure on, and base is simple anough but can any1 give any sergestions on this prob?

thanks for ya help ppl

 

[alexbleubolt]

all depends on the music, and as the HU doesn't have a sub output you won't get proper bass control on all songs

 

[rich_1989]

so th base control ure onabout is the reason why its not pickin up on all the bass lines? anyway ov fixin this prob without aftermarket HU?

 

[alexbleubolt]

not really, if you have fitted some cross over box (which you sort of mentoned above) you still won't really get the sound your after. best just get a new HU with sub out.
I had similar problems, but now i have alpine x100 it's perfect

 

[rich_1989]

ok m8 looks that way to me too....

i dont mind th cash 4 a decent HU its jus the standard HU is flush with dash in that black rubbery stuff, plus got the standard cd autochanger and the remote satalite control thing on th wheel i dont want loose, goin be a ball ache sort it out but need perfection!!! gonna go have a wack at routing the
in line converter though the amp in the high input option rather than RCA, wont do anything prob coz th whole situation is usless but goin try bits and bobs and have a propa pro check out the set up coz iv hurd you can get top notch inline converters which sort it out! but doubt that!
any sergestions on keepin th autochanger and satilite stick on a aftermarket HU?

 

[wallop]

Head unit settings;

Bass----'0'
Treble----'0'
Loudness----'off'
User EQs----'off' or flat/natural
Volume level----Just before distortion is apparent through front speakers...

Basic amp settings;

Gain/sensitivity control----set to minimum, (fully anti-clockwise)
Filter/crossover switch----set to LPF or low
Crossover frequency----set to approx 80hz
Stereo/Mono----set to Mono

Play a cd your familiar with, gradually increase the gain/sensitivity control on the amp until you hear distortion through the sub, then back off slightly.....

You can then adjust your crossover frequency to suit your own taste, (from a starting point of 80hz I would expect adjustment to be downwards)....

Use the gain control to match the subs output level to the output level of the front end, (the gain shouldn't be adjusted upwards at this point, if the front drowns out the sub, then lower the head unit volume level and then reset the amps gain as before), this process won't take minutes, it will possibly require tweaking over a few days to get right.....

Once you get it right your system should be fairly linear, so your sub can be heard at all volume levels without any hint of distortion.....

Once the gain has been set you can adjust your head unit to taste, but each alteration at the head unit will affect the RCA input voltage at the amp and as such will affect the gain setting.....Remember this to avoid clip at higher volumes....

 

[rich_1989]

thanks for your help ppl but giv into the dark side and brought a aftermaker HU took me 3min install and sound quallty is miles better as i knew, jus didnt want giv in. however will be able to reintall the satilte stalk with wiring addapter however CD changer is gone for good!!