Decision concerning subs

[Stratous]

I am just getting started with my automotive audio adventures. I started with a few power acoustic amps, polk audio mids and highs and two 12" audiopipe eye candy subs.

I was not happy with the amplifiers, so I picked up an audiopipe 30001.d to boost my base.

My delima is as follows. I want to increase my base, but add SQ and actually use most of the power available to me with the 3000.
My significant other doesnt want me spending massive amounts of money and I dont really want too either. I really want to get two 12" RE Audio SXX, but dont like the price tag and the fact that I will have wasted my money on the audiopipe 12's that I currently have. I could keep the two AP and add two RE Audio SEX 12's but would be pushing the limit on space available. I really would like to build a transmission line enclosure for the two SXX 12's.

what would be best
2 RE Audio SXX in a transmission line
2 AP's + 2 RE Audio SEX in sealed or
2 AP's in sealed and 2 RE Audio in ported (assuming I can find space)

The space I have is about 13"x48"x20"

If anyone has alternatives, please feel free

Thanks

[bjorno]

Originally Posted by Stratous

..I want.. add SQ and actually..best..
..2 RE Audio SXX in a transmission line..
..The space I have is about 13"x48"x20"..

Hi,

Suggestion: Try to use up all of your available space= Your External dimensions,3/4" wood in a single folded OD-TL box using two 2 RE Audio SXX drivers:
See the pictures where MJK:s and Hornresp simulation programs are used.

b

[johnr66]

You have a bout 6 cubic feet of internal volume to work with. What is the internal volume of the box you have now? Most car rigs are short on box volume.

[bjorno]

Originally Posted by bjorno

Hi,

Suggestion: Try to use up all of your available space= Your External dimensions,3/4" wood in a single folded OD-TL box using two 2 RE Audio SXX drivers:
See the pictures where MJK:s and Hornresp simulation programs are used.

b

The volume used in the OD-TL box shown in the pictures here above, is wasting half of the in reality suggested available space.

When I simulated the OD-TL (See the new pictures here below) I noticed that the FR was too flat for to be used in a car, so I decided to cut the volume in half but still hosted in the total available volume.

This operation resulted in the pictures shown in my first post.

b

[Stratous]

I have one enclosure with two chambers, one is 1.7 cubic feet the other is 1.3 cubic feet. The subs sound good, but I really dont like the location of the box.
I have a 06 ram, Since I still have children I did not want to remove the back seat, so I took the center console out of the truck and built the sub box there. It extends from the front seats to the back seat. I have since taken the back seat out and installed two bucket seats which opened up the entire center isle.
I would like to utilize that space for a new box, preferably a T-Line box with two really good subs. If I can convince my wife to allow me to buy the RE Audio SXX 12's then I will at least have the subs.

[Stratous]

I finally settled on three Skar VVX12's.
I plan to install them into a wedge shaped enclosure


Height 1 =20" (Back of wedge shape)
Height 2 =10" (Front of wedge shape)
Depth=45" (as measured from front of truck to back)
Width=15" (distance between seats)
That will be about 5 ft3, I may add an inch or 2 to the length and height to make it 5.25, or I will add a 4x17x15 on the bottom.
I would like for the subs to fire upward. The box will be in the cab of the truck placed between the front seats and extending back to the wall of the cab.
Can any assist me in designing a port, where should it be located and should it be a slot or tube?
I would like to tune for about 38hz. I have inserted the specs on the woofers.

Thanks

Fms 22.1Hz Res 101.8 Re 3.8 Qms 4.57 Qes 0.45 Qts 0.41 Rms 10.0 Kg/s Cms 0.16 mm/N Mms 330.8 gr Nref 0.14% Bl 19.8 SPL 83.3 dB VAS 59.2 L Rp 33.3 Lp 60.0 mH Cp 1126.1 uF Le 3.37 mH RMS 600watts

[bjorno]

If you connect 3 SkarVVX12 drivers in parallel you will end up with a requirement of 1 ohm load handling for your car-sub-amp.

The drivers are not well suited for ported designs.

A port tuning at 38 Hz lend to a very peaky low end FR tail because of the suggested '5cu,ft' = a too small volume..

..if not making the box tuned aperiodic ==> the port must be stuffed with damping material in order to achieve a flatter response.

b

[johnr66]

Placing the sub as far back as possible in the vehicle cab would produce the deepest bass. At least this was my experience with cars and hatchbacks. I used to shake the house with one 12" driver in a 2.3 cu ft ported box. If I moved the box from the cargo area to behind the front seats, the bass would become less deep and more boomy. I would consider a bandpass arrangement with the port towards the back. The drivers would be internal so the kiddies won't spill or put junk in them.

[Stratous]

I had planned to wire the voice coils in parallel and the subs in series for a 3 ohm load. As I am new to this hobby, I dont really understand the chart you posted. I do know that the manufacturer of the Skar subs reccomends a ported design.I had hoped to place a slot port near the back of the enclosure opening up to the cab. Would one port be enough or should I do two or even three. I intend to use one of the available programs to assist me with port placement. Building a sealed enclosure is easy, porting properly seems a bit more envolved. Does anyone have a recommendation for the enclosure design program?

[revboden]

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