Adding subs, questions.

[rotwiler]

I bought a custom made fiberglass box off here from another forum member. Box is made super strong, so my question. Airspace should be around 1.7-8 total. Holds 2 (12s) sealed but is not sperate airspace. Was thinking, should I go with a nice 1000 watt rms subwoofer powered by a 900-1000 watt rms amp or go with 2 500-600 watt rms subs? If I went with 1 I could just cover the sub hole. Other question, I see the PAC amp pro 4_adds full sub freq, but at $249 seems high if just using for a sub. Any other options out there to get all the lows not cut by the factory alpine amp?

 

[autokraftgt]

Watts aside, you need to find two subwoofers that requires .80-90 cu/ft airspace/EA, and performs well and fits. OR find a nice sub that likes more airspace near the 1.7-1.8 cu/ft and fits. The single most important factor is finding a sub that suites your enclosure whether its a single 12 or two of them. If you go with a single 12" and the enclosure is a bit big...you can add something to take up some volume in the enclosure to get you where the airspace needs to be. Throwing a sub into too small of an enclosure (or too much airspace) will negatively effect the performance and sound of the sub(s). A sub in a proper enclosure with 500 watts will sound night and day better than a sub that is being choked/or swimming in too much airspace with a 1000 watts. Remember to take the subwoofers "displacement" into account when deciding on a sub...airspace requirements are after the subwoofer's displacement has been accounted for. Your second question has been covered a zillion times but Iam sure someone will chime in on that subject.
Personally I would try to find two 12's that perform well under a cubic foot each....however, a super nice single 12" with a 1000 watts should provide plenty of output as long as it is happy in the enclosure. My current project is a single Arc Black 12 with 1000 watts in a 1.1 cu/ft sealed enclosure

 

[TomT]

A pair of these shallow mount JLs might be just the ticket.

http://www.woofersetc.com/c-23-subw...dual-4-ohm-w3-thin-line-series-subwoofer.html

Have you picked out an amp yet so you can determine the optimum final load needed?

 

[rotwiler]

I haven't decided on amp yet. I have a old school mtx 2150x that has been laying around unused for years, but is 2ohm and only like 500 Watts rms. It is missing the line level input harness, so would need a loc, so may just go with a different amp. Measuring depth, I have enough depth I don't need to do a shallow sub.

 

[TomT]

You have depth but there are not that many good 12" subs that will work in .75 cuft of airspace (assuming a pair and deducting for displacement).

If I had your box right now, I'd go this route:


Wire the subs for a final load of 4 Ohms (this makes the amp work less hard) and that Zapco will give them a hair under 1,000 watts.