you think if i lower the treble on the headunit it will go away, i usually keep the treble all the way up
didnt think about that
i'll see what happens tomorrow if i turn it down
no, that's not what i'm saying at all. if you turn the treble down for the entire system all you'll get is a dull sound.
quick crash course:
on sound properties, click here
after you've read that, bass sound is generally anything below 250Hz. Treble sound is generally anything above 5KHz (that's 5,000Hz) anything in between is generally known as midrange.
subwoofers are designed to run at low frequencies, usually below 120Hz. this maximises the sound quality you get out of the speaker and it has a huge effect on the overall sound system performance.
subwoofers are generally connected to amplifiers. what you're trying to do is filter out
any sound with frequencies higher than around 120Hz (i use 60Hz) out of the sound signal BEFORE it reaches your subwoofer.
in order to achieve this, you need to split the signal coming out of your head unit. some head units can do this. mine can. all i do is go to the "low pass filter" setting and set it to 60Hz. what this does, is: it sends a sound signal that contains only frequencies that are 60Hz or lower to the amplifier.
if your head unit doesn't have this, your amplifier may have it. some amplifiers have a "low pass filter" built into them, either via switches or via a knob. see if your amplifer has either of these. and if so, set it to something between 50Hz and 120Hz, experiment a little. so the signal going to the speaker is still being split, but in this case, the amplifier is doing the job, not the head unit.
if you don't have a low pass filter either at the head unit or at the amplifier, you'll need to get a crossover network.