Setting w/ 2x12" 800w max subwoofer - Volfenhag ZX-8300 Car Audio Amplifier

It sounds like the subwoofer may be experiencing a problem with its power supply or amplifier. The "boom" sound you are hearing could be caused by a fluctuation in the voltage or current going to the subwoofer. I would recommend checking the power supply and amplifier to make sure they are functioning properly. Additionally, you may want to check the subwoofer's settings and ensure that the crossover frequency is properly set. If the issue persists, it may be best to contact Harman Kardon customer support for further assistance.

set gain low. the other is your filtering frequency as at what hertz you want to listen at switch threw them for your best sound.

HPF on/off affect Sub woofer output. Check other items too. Do you have the instruction book? if not visit books.jvc.com

Buy a quality 2 channel amp. About 600 rms and set one channel as your highs using your crossover and then the second channel on "low" position for your sub. wire directly in to your low's channel with your sub at 2 ohms and then wire your speakers to the other channel.

off the same amp? you have two way different sounding speakers man. you can buy 2 identical speakers from the same company and brand and series and they will play differently every time. you have 2 speakers with nothing in common so you will hear a difference and maybe interference because of the different ohm levels.

I have the same set of speakers and im running a kenwood 2 channel amplifier thats bridged and it works well.

there is four diff. modals db-12 street 1000watts max 4ohm.
dbxi-12 1500 watts max 4ohm
dbxi-12 1500 watts max 4ohm single voice coil.
dbx-12os 3000 watts max 2ohm.
hope thats what u need if u need more help feel free to email me [email protected]

you best type of enclosure will be a sealed enclosure or you can build it with a partition in the middle seperating the 2 subs and port each side.

heres a link that will give you the specs for your sub
http://www.lanzar.com/manuals/MAXP104D-124D-154D.pdf

Sensitivity is a representation of efficiency. The higher the efficiency, the better the sound quality.
Xmax is a measure of the "throw of the cone peak to peak. This is a direct representation of the volume of air the subwoofer will displace..
A High X.Max subwoofer will displace more air - and therefore produce more SPL in a vented enclosure.
Sensitivity on these subs aren't crucial, because the customer is looking for LOUD and will purchase a large class D Mono amplifier to power it - characteristically low in sensitivity as well due to the way the power is inverted. Highly efficient, yet low sensitiviy.
I am definately a basshead! My show car has (4) 15" Cerwin Vega Stroker PROs. (one of the most highly EFFICIENT high xmax subs available) (86dB). (36-44mm Xmax (adjustable for SQ or SPL)
If you are looking for SPL, High XMax, Low sensitivity, and lots of power is the way to go. Generally, to increas SPL by 3dB, yuo must either increase surface area of driver 2x or double the input power. Slot ports, aeroports, and loaded horn ports can also increase your dB level by up to 3dB as well.
Properly constructed enclosures have an effect as well. Instead of wasting some of your power on vibrating the enclosure, it should be braced properly to reduce the wasted energy.
All of these tips will add tou your satisfaction of the product. You can make a $100 sub sound phenomenal in a proper enclosure, and a $400 sub sound like $hit in a prefab or poorly constructed one.

Your original question - with all things equal except the subwoofer, the subwoofer with the higher Xmax should yield the most SPL - due only to the fact of air displacement.

If you have additional questions or need clarification dont hesitate to ask.

You're in warranty. Appers to be a common problem. Soundstixks should either tell you how to fix it or replace your system.