ok, my friend is looking to get 2 15's for his car, I told him about the mags and he doesnt believe me, I told him 1 15'' will slap hard enough but the still wants to get 2. Can someone please let him know that 1 15'' will be enough bass.
Your friend has a lot of things to consider. If he plans to run over 1500+rms or even less (depends on cars stock alt and such) which IMO is the range where you need to start upgrading your charging system. So instead of getting two 15"s get 1, and then use the other money to upgrade your charging system. Would be nice to upgrade anyways. And then add another subwoofer and amp later. Thats my opionion, but it depends if he has the money or if he is going to do the charging system upgrades already. Show him some videos on www.realmofexcursion.com