I have about $300 budget. Thats maximum... Including me making a box. I was thinking 4 infinity refrence 8" subs... Or 2 10" obsidian audio subs. Or like one ssd 15... Idek if i could fit any of this in my truck where i want it. The back seat behind the drivers seat.. So i still need 2 seats in the back aswell. Its a toyota tundra access cab. I hopefully an getting a hifonics brz.1800 on monday for a bday presant... If not iv been wastig all my time thinking and hoping for it. But id like to try and fit any of those in back there for some hard hitting bass.. I was told a price for the obsidians and it seemed fair.. Im kind of leaning toward them. I feel that the 8s would be alot more fancy looking. And have alot of tight punch bt not get quite so low... I believe the 15 would hit the lowest... But the least surface area so wouldnt be as loud... So im mostly stuck between the 8s and the 10s. The 8s just would look sexy... But they also wouldnt handle as much power... Not quite as much.. Im planning on running at 2 ohms 1200rms. Am i heading in the right direction? Idk about the sub choice for the eights.. They are cheap and "pretty" so i liked them. The obsidians should bang tho... So opinions please! And if i dont get the amp im sorry i even posted bt im thinking positive here...

Well the obsidian 10s are out... I read the email wrong... Terrible price. But if someone could reccomend another brand of 10" subs that would be great.

a pair of sundown sa10's or ssa dcon 10's

Single 15" has more cone area than two 10's (about 30% more cone area) & only a hair less than four 8's (though depending on the actual Sd of the 8's, the single 15" might end up having more cone area), however an SSD is going to have significantly more excursion capabilities than those Infinities so overall displacement would be significantly higher with the single 15", which means potential output would be the greatest with the single 15" out of those options.

How much room do you actually have to allocate towards the enclosure?

Also there's absolutely no reason at all four 8's would have more "punchy bass" than a single 15".

As of right now out of the options you listed I see no reason not to go with the single 15" as long as you can fit a proper enclosure.

Ahh id have to go and measure.. But its an odd shape and stuff but i definatly could fit like one 15. I would probably just use round ports and make it easy on myself.. Do i want to use the roof to load off of? I aim the sub towards the back of drivers seat and port can go anywhere really.. Just i dont want people hitting the sub with the two seats still used quite frequently. But honestly i couldnt give you a number for the space... I could probably fit about 4 or 5 cuft... If the box is formed to the seat and stuff.

The SSD is an excellent sub woofer. Very versatile and can perform very well. Quite a good value and made here in the USA.

4 8s - 200.96sq

2 10s - 157.0

1 15 - 176.63

in theory 4 8s have the most cone area but if u account for suspension & actually cone area then 1 15 shud be very close

id keep things simple & do 1 15

I am not sure how you would fit 4-5^3ft net enclosure in your truck and have full use of the rear seat. It is a 70/30 split bench, right?

Have you looked under seats or behind the rear seat area as a location for a enclosure?

As I recommended in another thread the Sundown SD-2 might be well suited for your install. The mounting depth of those drivers is minimal compared to most and no pole vent. This opens up the possibilities for very small enclosures which may not work for other drivers.

I give up the 30 part. Lol so i have the passengerside backseat and the middle Seat the driver side is all for subwoffer! Haha but im gunna order the ssd soon. What options should i get?

I changed my mind to the sound stream rub.1600 aswell.