Obviously you realize that your overloading your subs capabilities in fact its next to impossible for any single sub to be able to accurately reproduce this kind of music.
No,your missing a big part of the picture,it hasnt sounded bad on every system you've played the music on.
Take a look at the table top's bass response capabilities,it has none or very little,no matter what you do its only going to reproduce the highest of bass notes,more like deep midrange than a real bass response,this is why the vocals sound clear on the cheap system,your klipsch has the capability to reproduce the lower bass notes & with so many hard hitting low notes going on at once & at the speed they are happening there's no way any standard single sub will keep up,it's not going to happen.
You've got some choices in solving this problem,first off & the easiest & no cash solution is to take some of the load off of your sub,i would guess that your sub is set at it's lowest possible setting,this is not good for that type of music,you can adjust your sub to help clean up the vocals & to get a cleaner bass response.
Start out with the db level of the music just beyond the point where the bass gets muddy & start raising the bass response until the vocals start to sound right & the bass becomes clear,you will lose some bass response but it shouldnt be very audible & it should stop the smearing of the bass,the response you will loose is down in the 10hz to 20 hz range & those frequiences are more felt than heard but they will reek havoc on a sub that is multi tasking.
If after doing this & the vocals & bass response sound the way you want but you still miss a bit of the IMPACT OR SLAM THAT YOU FEELyou can restore that effect by adding another sub that can dig very deep to atleast 20hz but preferably 10hz & let the other sub reproduce all the higher octave bass notes.
You need to understand that the type of bass response required to handle these type of constant low octave bass notes are way beyong most single driver single xover subwoofers capabilities to start with,a normal bass note in the extreme lower octaves is more like a slow droning effect where the single note lasts for several seconds & the notes are not a constant,in death metal these notes are constant which is whats leading to your sub being overloaded & over worked & is gaurenteed to be causing all of the smearing of the bass.
