Right now atm I have 2 Pioneer Champ. Series Subs, with a Kenwood KAC-9105D Powering them. Planning to atleast Upgrade my Subs, and I am really interested in Fi. Going to SPL here, but dont want to spend a TON for my setup. So I was thinking of getting 2 Fi SSD12s but they would cost me almost 500 just for the speakers after shipping. And I would most likely have to upgrade my amp because it probably wouldn't push them both hard enough. OR I could go with a Fi SSD15 Will be about half the price and I wouldn't really have to upgrade my amp because it pushes 900 at 2 ohms an >900 at 1ohm. So my question is in a ported box would 1 Fi 15 be comprable to 2 Fi 12s.