The VBT (TBI) Magellan passive subs are small, attractive and very quick and tuneful, and should mate well with your Maggies. Put one in your corner, or for even better response use one beside each speaker.
If you want to move, more air, I've also used the RBH 1010 subs with great results (two 10" aliminum drivers). Clean and tight. They make both a passive and active model.
I agree with Java that the interior of a hot, vibrating subwoofer cabinet is not the best place to put an amplifier. People spend tons on amp stands and footers and vibration control and then use powered subs where there's more vibration going on than anywhere else in their system.
BTW, I also agree with Gallant that diploe subs are a really good idea with dipole mains. They're a great answer for problem (boomy) rooms. I'm presently using some Linkwitz Orion diploes to great effect.
If you want to move, more air, I've also used the RBH 1010 subs with great results (two 10" aliminum drivers). Clean and tight. They make both a passive and active model.
I agree with Java that the interior of a hot, vibrating subwoofer cabinet is not the best place to put an amplifier. People spend tons on amp stands and footers and vibration control and then use powered subs where there's more vibration going on than anywhere else in their system.
BTW, I also agree with Gallant that diploe subs are a really good idea with dipole mains. They're a great answer for problem (boomy) rooms. I'm presently using some Linkwitz Orion diploes to great effect.