Joe X

Those amps will give exactly the same power connected to 2 ohm as they give connected to 1 ohm, you need to do nothing, here is what the amp specs say: Same 1500W at 1 ohm or 2 ohm. Only if you connected to 4 ohm you would get less power.

The power 1500bdcp is a constant power amplifier, wire each sub to one ohm (coils in parallel) and then connect one sub to each amp to get 1500W to each subwoofer and you are done.

Check that modeling: Fi 4.11 18 Sundown Zv618: Both based on a 7 cubic feet net @32Hz enclosure. The Fi has a 4 dB advantage over the Zv6 at their rated power and justifiably so since the Fi is a 4500W driver vs 2500W. Check out your fi parameters, I am sure you picked the 12" driver parameters instead of the 18". It is very easy to make a mistake with modeling software, so easy many people don't rely on modeling.

I don't know that worst loses happen in glass windows, rather it occurs in large thin metallic parts like the roof of large vehicles or where ever you se flex happening, Any place you see flex happening you need to apply deadening. Anyways when you have a system level issue you need to post what is your full system components, your electrical (including wiring) and what is your vehicle, your box specs and a lot of pictures. Lastly a wall is not a box firing forward subs and ports, what a wall does is reducing the cabin size, increasing output significantly, a box specially in the middle of a cabin firing forward will probably do worse than a properly placed subs up / port back box.

Each of the two lines ideally should have a 125A fuse if the max current draw is 250A.

Two 12s on your space is possible but would need to look for another form factor, for simplicity here is your request 2x10 T1 subs: Assuming you have the trunk version of that vehicle aim subs and port back, (figure is just an assembly guide). For an amp I would suggest you the pretty decent quality D4S JP23 amplifier, it is half bridge, does rated and has good THD figures for a class D amplifier it's $299. You would wire coils in series and subs in parallel for a final load of 2 ohm. Also you may need alternator and battery upgrades for any > 1K system.

Very fer people have that device as is pretty expensive, the manual should tell you how to go about it but if not, you can always have it looked at by a pro installer.

You can do 12s if you want and be much louder for the same power, as for the Rockford fosgate brand they are good but they are on the expensive side you can go for these instead in the 12 size: https://stereointegrity.com/product/sql-series/ Anyways if you don't care for any of the above a 2x10s box is very doable on your max dimensions Pick an amp that matches or exceeds the subs power handling. just avoid full bridge amplifiers unless you plan for electrical upgrades.

Best thing you can do is transfer youir CD to USB in a PC or: Check out this thread:

Just going by the subs manual for each subs you need 121 liters and 41,2 square inches of port area tuned to 30Hz So the box need to be 242 liters net and 82.4 square inches of port area at the same tuning. So how you get 82.4 square inches with 6" round ports, one 6" round port is 28.2 square inches and 3 are 84.2 almost exactly what is needed so: 3 6" round ports is what is needed according to manufacturer specs based in a 242 liters box and rated power. Since you are overpowering you probably need more port area but at least you do need 3.

You need to open the box (say remove the sub) and connect the DD-1 to the amp output terminals, no other way. You can instead get a box without an integrated amp and then buy a mini amp such as this: https://www.sonicelectronix.com/item-43424-Rockford-Fosgate-Punch-PBR300X2.html

It comes down to the speakers you have purchased If you can list the models of your head unit and the speakers, tweeters, subs that you have purchased it will be easier for me to answer specifically.

The 3 way mode lets you have a fully active front stage, no rear fill and a sub channel and for that you need a 4 channel amp and a sub amp. Likely you use that mode for a sound quality application. Or you can choose two front channels, two rear channels and a sub channel to have the functions you like, you also need 4 channel amp and a sub amp. In the rare case you wanted a fully active front stage and a fully active rear fill you would need a couple of active 2 channel crossovers OR a multichannel DSP and two 4 channel amplifiers and a sub amp, you can use all the functions of your head unit and stay fully active BUT that is a lot of equipment to install. I don't know anyone running their system this way but it's possible.

Who knows but the Taramp Smart Bass 8k is a constant power amp with flexible load options which the others don't have. As you know all those full bridge amplifiers like extremely solid electrical that provides 12.5-15V at all times, if you don't intend to have that better choose a half bridge alternative.

The subsonic (high pass) is generally 4th order not 2nd order filter in most amps so it will need to be set higher to better control excursion, also, WinISD doesn't account for cabin gain so your frequency response just show how the box will play outdoors. But you can still compare your plot with a 4.75 net box tuned to 29Hz (the prefab) to see how much are you expected to gain, that actually is useful information you might be interested in.

There is a 6+ dB gain from doubling power and cone area, There is a 3 dB gain from using professional round ports (around tuning). Those can be dramatic gains as long as you can make it all work as it should.

With that sub the DC resistance is given per coil and BL is given for coils wired in parallel so Re = 1.6 ohm. What is more serious is that they don't provide Xmax which limits your ability to predict maximum power for your situation and where to set your subsonic filter. The parameters you are going to use are the only ones you need to have, the others are not necessary, manufacturers usually will give parameters measured with coils wired in series, if you need to wire in parallel you need to divide Re/4 and recalculate BL through the program, you will get a lower BL value. If you need to measure parameters bear in mind that new subs need to be broken in before any measurements take place or the parameters you get are no good for box designing.

here are the two basic types of 6th order bandpass enclosures: Parallel tuned: Series tuned: As you can see with bandpass enclosures you can never see the drivers from the outside.

Sure you can do that for some moderate improvement, larger improvements involve greater cone area like for example doing 2 15s, if doing a larger than recommended box and tuning higher requires you setting up your subsonic filter higher to prevent sub bottoming out.

Depens on what you mean by "together" but if I imagine right you would have a parallel tuned 6th order bandpass, still that would be useless because in such enclosures the chamber sizes are of different sizes, port area and port tuning of each port are vastly different, in other words that wouldn't work at all.

That looks all wrong, check out this thread to learn to use it: Those enclosures are top slanted, look for a commercial design made for your vehicle and try to see how it is done, generally subs forward / port sideways, these boxes are hard to build try to find a prefab for your vehicle that has the right specs but not as expensive as the one from that guy.

Find the volume level at which your head unit clips and never use at that level, the hard part is going to be finding clipping at the output of the amp since it is inside the box to set your gain properly, you would need to open the box and setup the amp gain that way, very impractical.

i am going to guess you have the ZVX 18v2, the prefab box is almost the size of the suggested box, only the port area is a little low on the prefab but not low enough to be of concern if you are just playing music, here is the difference between prefab (yellow plot) and the suggested spec (red plot) in frequency response: Recommended : use the box sub / port up reverse mounting the sub to see any improvement in performance, Prefab with low port area but performance hit to rated power seems low, only marginal improvements from a rebuild to recommended specs.

You are running 1300W of power in your audio, no need for any other electrical upgrades if just playing music, No need to be checking your voltage unless something in your car is not working properly, the amps will work just fine in the 12-14V range no problem. If you are just curious as to why the voltage is being regulated the way it does, just have your electrical checked and then ask your concerns, to me, if your car works fine and your audio works fine I would just leave it alone.

A D2 sub can only be wired to 4 or 1 ohm so my suggestion is to get an amp that is one ohm stable delivering at least 1200W RMS such as: https://nvx.com/products/xad12-1500w-rms-x-series-full-bridge-class-d-1-ohm-stable-monoblock-amplifier Also when running more than 1kw of power is necessary to check your electrical to be able to support the load and if so check that it is in good condition, more so if you intend to run full bridge amps such as these NVX.