A:AnswerT15 would be best. You get a pair for around $90 but it depends on if you’re using a receiver or amp. You may need powered speakers as Klipsch makes some good ones.
A:AnswerYes, but it's cost prohibitive.
By the time you replace the Bass radiators with real drivers
& a proper crossover for them?
You're better off buying the Pioneer SP-F52's
which these POLK's were made to compete against
but fell way short.
Just don't buy this speaker to start with.
Spend your cash on a better, Hi-Fi speaker.
~ peace
A:AnswerThe bottom speaker is just there to accentuate and reverberate the sound of the others. They put a lot of R&D into this effect and how it was affected. It helps with mid and low sounds.
A:AnswerThese are 6 Ohm speakers, if you have an impedance setting on your amp like my Yamaha does then you set it to low, and if you run more than 2 speakers the other speakers must be the same Ohm rating or higher. Like these 6 Ohm speakers, and say 2 more 8 Ohm speakers in addition. You may also use a speaker selector switch to add in others if your amp can handle it to get the best sound.
A:AnswerThese speakers only have one active driver. The lower two are passive radiators. They have no sound passing through them, they are only there to enhance the bass output.