Joe X

You need to verify the model of the subs by removing one and verifying that is: Titanium Power SD1255 Here are the specs: I found: FS-38HZ QMS-6.8 VAS-0.906 cu. ft CMS-0.0123 in/LB MMS-6.87 OZ QES-0.5 RE-2/4 OHMS DVC BL-4.3 LB/a QTS-0.466 Pe = 1600W peak

Forgot replying to you, my apologies you need a 4" round port for that sub and the dimensions given are insufficient, I recommend going with a slot port which can turn inside the box and gives you options on box dimensions.

You can forget about impedance rise, as long as you are not a competitor or you are not fine tuning an exotic type of enclosure, you just need to have a good working electrical system that is in the level of the amp you are using, good wiring correctly installed, a good amp that does the power it claims, and proper gain settings procedures, it is worth learning about that as well as owning a cheap little scope or a DD-1, if you can source 2K to your subs you will see a big jump in output and you will be pretty satisfied with the results.

It is recommended that you use an amplifier that provides RMS power at least the same RMS power of all your subs, in your case 2500W , if you like skar I would go at least for the RP 2000 and light electrical upgrades for your car. the RP2000 is a tried and true amp and at 220 is pretty cheap. generally speaking I would recommend Korean half bridge amps which can work fine on minimal electrical upgrades.

The Skar Audio RP 1500.1D 1500W RMS amp which has been tested to do rated power requires a 120A fuse. So your amp simply does not do rated power at all just looking at the fuse it uses. And the fact that your 60A fuse in the power line never blows just gives you an idea how little power you are actually running looking at the math Power = 120A x 13V = 1560W or just above the power rating. For 60A fuse: Power = 60A x 13V = 780W which never blows so you not even that (you don't even need electrical upgrades at this power). Factoring in amplifier efficiency at 60A you would be delivering about 300W to each driver but again not even that. I am going to guess you are actually delivering 200W to each 1250W driver or barely moving. If you are comfortable at that level you could just leave it like that but what needs to be done to get those subs moving is a new amp and an electrical to match, a cheap amp that does 2500W RMS is the D4S JP23 1.5 which is 299 and is ideal for systems with light electrical upgrades.

There are many mini amps, the Rockford Fosgate amp for sure is high quality and does above rated power but there are many others, check them out: https://www.sonicelectronix.com/ci1743-mini-amps.html

You do two 12s in that vehicle, but anyways post your max dimensions for a box height, wide, depth and what amp you have.

What is your amp brand name and model? What are the specs of your wiring and electrical (battery,alternator)?, do you have a big 3 upgrade?

As long as you have used glue rather abundantly and left the box alone enough time for the glue to dry completely you should be fine, the parts come already cut so caulk or other stuff to patch up holes should not be necessary. EVLs motor is not that powerful or the subs need that much port area so I say that even if the box is prefab it should do fine, 4 cubic feet net and about 50 square inches of port area should be enough. You should leave the 6x8 speaker slots in the rear deck open and open a big hole in the center and hope for the best. Look up proper gain setting procedures for your electronics which involve getting a cheap handheld scope or a SMD DD-1 to do the job correctly. Let us know how it went.

You can overpower a sub without clipping and yo can get a sub blown without any clipping, The thing is that a clipped signal contains significantly more energy than it's undistorted counterpart so you have to avoid clipping at all costs. The amplifier can't tell if you are overpowering a driver, the clipping light just means that the amplifier is generating clipping distortion even if you can't hear it and that has nothing to do with the sub.

A few questions: 1) what vehicle is it 2) what music you listen 3 how much measured space you have for the box HxWxD 4) what sub and box you had in your car you liked the lows if any. Answer those and I should be able to tell you what may work.

The ski hole is not going to be enough for a ported setup and you would need to open up the rear deck, sure enough it's a mercedes and probably you won't be inclined to cut holes on it so you may have to live with whatever you get or do a 4th BP blowthrough which the sub seems not ideal for it.

I am thinking that if they offer that 0.5 ohm warranty and you purchased that warranty then you simply had the awesome luck of getting a dud, as you say it didn't even bother to go into protect, I think you will get a replacement amp tested to work well at 0.5, still I would absolutely pass on using the replacement on the same sub and just sell it or keep it for a one ohm setup of the future. As for the CAB go it should work perfect and cool at 2 ohm.. hopefully, let us know how did you like it besides the annoying size.

One important thing here is that many european cars need the rear deck opened so that sound waves get into the cabin so you may need to do that. You can have port to the side, many SPL designs go that way, digital designs enclosure suggestions use port to the side, you just need abundant clearance for the port to work well. Also bear in mind that WinISD is a basic program and the plots obtained are really coarse representation of what you will get, you need to experiment where to aim sub and port, what location is best for the box, better aesthetics and functionality in car audio many times mean worse performance, my recommendation is setup the way is best for sound, for example fire back the sub and since it is exposed use a grille to protect it if that's better than firing forward.

1) larger enclosure plays peakier with better low end but with a loss of sound quality. You need to watch out for over excursion at lower power levels with a bigger box, you can check that with WinISD, keep maximum excursion below Xmax at all costs. 2) port area is judged by airspeed, lower airspeed is better, for slot ports I would keep around 26 m/s or less, for aero ports if its just round pipe would keep within 30 m/s, if it has professionally designed flares 35 m/s or a little more. If the form factor of the port is high or you have turns in the port its better to go for lower airspeed. 3) with WinISD add a linkwitz transform filter to simulate cabin gain frequency response, bear in mind that you need to disable it when looking at all the other plots.

Try to turn on just one single amp and do it with the car running this time, see how that goes.

Port area needs not to be an exact value, just needs to be large enough for air not to rush in and out too fast which hurts your output and produces noises. Generally a 16 times net volume of the box in square feet should be a safe bet but evaluating the physics of the situation (driver, box, power) you can figure a much more adequate number as I did in my last post, if you give some more port area than needed your box becomes larger and heavier than needed to virtually no gain in performance. The only thing you need to bear in mind is that the resulting port is not too long like more than 40 inches

Yes but the sub needs to placed in a way that is away from the inner end of the port.

Do the box so you can fire the subs and port to the rear to avoid rattling and open up that rear deck and hopefully enough output reach the cabin, that is actually THE problem with those VIcs, lots of space but then sound gets trapped in there, build a custom rear deck or as you say get some grilles so that it looks nice. Also go for a larger box with generous port area so that the box is efficient even if it plays a bit peaky, you will need every bit of possible output so that you can still get a decent experience at the front seats, let us know how it went.

The sub will easily play below 35Hz, it is no sundown X but it will still do pretty good, take good care of it setting your subsonic filter properly and not letting it see too much power, place the box near the rear end of your vehicle to play louder.

Newer subs taking less space is pretty common these days and the way of the future, you can see space wasting brands like DD audio and SoundQubed now have many models working in fairly compact enclosures.

So here is a suggestion, power: to sub rated, amp subsonic filter to 28Hz, minimum port clearance 1 1/2", figure is just an assembly guide: NOTE: If building outside you need to build a cardboard dummy box to test fit in it's way inside. NOTE: your subwoofer looks beat up and poorly repaired don't push it hard at all.

Is a single reflex bandpass box ported directly to the cabin, easier said than done: It's an advanced project that you can get done wrong in a million ways. In fact I don't know if it can even be done properly.

I believe that you can place a single 15" in that trunk size instead of a single 12", doing that would make you as loud as if you were powering 10000W RMS due to the increased cone area.

What is the vehicle?