The easiest way to get more boom is by putting in more subs rather than more power. For an example, if you wanted more bass, and you had the choice between:
2 subs running at 200 watts each or
4 subs running at 100 watts each
They're both pulling the same amount of power, but you'd theoretically take the second choice. This is because the power consumption of an audio system is expontial. This means when you double your amp power, you're not doubling you volume.
Each time you want to gain 3 dbs in volume you either have to double your power or your cone area (doubling up on woofers). So if a sensitivity rating of a sub was like 88 for one watt of power, to get to 91, you need to go to two watts. Then, to get to 93 you need 4 watts. Then to get to 96 you need 8 watts. To get to 99 you need 16 watts. So as you can see, those competitors that get up in the 150's and such, the power required for every extra watt is costing them in blood.
So if you can't pay in blood like that, you can pay in space by just buying more subs that way. If you had two subs in parallel, that would draw your 2 ohm load and you'd be running 2 subs on one channel. So you'd pull out twice your output and double your cone area, and you'd be doing that for both channels.
I didn't mean that you'd have to buy new subs and an amp, just that your other choice is to try and buy a more powerful amp if you didn't want to get more subs. Sorry about that.
Technically, as long as you set the ohm loads up right, you can have one amp powering a whole bunch of subs. In one old car audio mag, there was some guy who put like 20 or so Bazooka tubes to two amps.
There are lots of ways you can achieve this. Another way might just be to put your subs in a bigger box to allow for more excursion. It'll give the bass even more boom. Or just start buying cheaper subs and put lots of 'em in!
