What is the problem here?- subwoofer related

[Explorer96xlt]

well, i got my Kappa perfect 12.1's all installed. They are installed correctly, my amp gain is set correctly, and they are in a 1.00 cubic foot box (a peice). My problem is that they dont sound like they are playing to their full potential. I have read reviews on the KP12.1 and all the reviews have been super positive, but not these subs, theyy have sort of a muddy sound to them. any ideas?

I havent yet installed my 4gauge wire(previously 8ga), which i plan to do this weekend, and i havent stuffed my box with polyfil yet, these are my last two options.

thanks in advance

oh yeah, and i am using the infinity 611a amp, so its a strong, reliable amp, not a cheap one..thanks again

-alex

 

[DOZIER]

Maybe you could try adjusting your amplifier a little. Play with it and see if you can change that muddy sound to a nice crisp thump.

 

[Explorer96xlt]

i've adjusted it everyday now for the past week, and still cant figure it out, im a little leary about adjusting the HP and LP crossovers, b/c i dont know what i'm doing in that area, but i THINK i have the idea of it

 

[Wagonized]

make sure both coils are connected if its a dvc

where are your crossovers set at in the amp and deck?

 

[Dan Whitaker]

i've adjusted it everyday now for the past week, and still cant figure it out, im a little leary about adjusting the HP and LP crossovers, b/c i dont know what i'm doing in that area, but i THINK i have the idea of it

Make sure you have the LP filter on. This is what you want for your subs.
LP will let higher frequencies get to your subs which is not a good thing.

 

[Explorer96xlt]

They are single coils, my lp and hp filters are both set in the middle, i read that the lp is only used for ported enclosures, which i dont have, i have a sealed enclosure

 

[Dan Whitaker]

They are single coils, my lp and hp filters are both set in the middle, i read that the lp is only used for ported enclosures, which i dont have, i have a sealed enclosure

That is incorrect. You want the filter set on LP regardless of sealed or ported.

With it set where you have it all frequencies are getting to your subs. you only want low frequencies to go to your subs. This is more than likely why you are getting a muddy sound.

Click on the Real Car Audio link below in my sig.
There is a lot of infromation there.

 

[Explorer96xlt]

so i want the LP filter all the way up, and the HP filter off?

 

[Dan Whitaker]

Yes. Subs are designed for low frequencies only hence the name sub.

Think in the terms sub-zero tempatures.

The car audio forum I belong to as mentioned above is a good place to learn the technical aspects.

It is a very freindly site.

Like here, flaming has a zero tollerence.

 

[Explorer96xlt]

what is the point of my HP filter then?

 

[Dan Whitaker]

The HP filter is what you would use for amping your full range speakers be it your front or rear ones.

 

[Explorer96xlt]

i see, i see..alright, i think i understand now

 

[Wagonized]

A HP filter on a sub amp is also reffered to as a subsonic filter. Usually set around 20-30 hz so the sub doesnt play too low of frequencies and bottom out.

 

[toypaseo]

I am voting that polyfill will solve your problem.

 

[Explorer96xlt]

while i'm at it, can anyone explain clipping to me? My amps clip light will sometimes go on, but the subs dont sound distorted at all, dunno..

 

[davesexplorer]

The highpass on 2ch/4ch+ models should be used to protect mids/woofers/tweeters/coaxes etc. from low frequencies that a smaller speaker isn't designed to reproduce. If the manufacturer lists frequency response say 85-22khz for a set of coaxes, you'll want to set it around the lower figure moving it up slightly if you are not sufficiently powering it.

Some mono amplifiers come with a "hi-pass" filter too, termed subsonic or infrasonic filter, these will act in the same manner as above, blocking out lower frequencies that some subs simply weren't made to produce, if the cabinet is ported you can cut off the frequencies below tuning etc. If this can be turned off, turn it off, you shouldn't need it in a sealed enclosure like you said.

The lowpass shouldn't just be "turned all the way up", typically when I start setting things for the first time I'll use 80hz if the rest of the speakers in the system are quality and play decently low, otherwise 100hz. That means the amp will send the subwoofer roughly 100hz and down (without getting into the specifics of slope/ db/octave etc.)

What head unit are you running?

(I know I repeated some stuff but it fit in with what I was talking about.)

 

[Explorer96xlt]

Im running an Alpine cda 9857 with 2 volt preamp output

 

[davesexplorer]

Well you should have 650ish watts, a couple nice efficient subs, the cabinet affords each 1ft^3 sealed - within their specs...

All I can say is play with the settings, I see the amp has a DBO circuit, which is a bass boost/subsonic filter all in one.. sounds kinda like what my orion 2500d's had. Try with it off, playing with the settings, on the alpine - turn the subwoofer output all the way up (should be like +15 or so) this will get the maximum subwoofer rca voltage out of it, then get your gains set.

 

[splferrell]

i know whats wrong small boxes 1 cu.ft. have a higher fb when you try to play low hz it makes it sound muddly you will have higer spl with the small box but i would go bigger if you have room i would recomend ported box tuned low 30~25hz

 

[splferrell]

clipping is were the input singal is not the same as the output,caused by turning it up too loud or by the amp gain being up too high, a clipp singal can burn up a subs coil faster then too much power a tad bit into clipp sould be ok. frist turn the radio up to were it sounds best then turn your amp gain up till its a lil bit into clipp