What are the smallest speakers that are clean and flat down to 20hz?


Also what bass driver or drivers do they use?

Thanks.
128x128mapman
Yg Acoustics Kipod II Signature. Bass is covered by only an 8" driver in active sealed inclosure.  Deep, deep bass. 
What are the smallest speakers that are clean and flat down to 20hz?

Also what bass driver or drivers do they use?

Thanks.
mapman

Without being EQ'ed the lowest bass I have heard from a large sized bookshelf, has been a pair of Sonus Faber Extremas, that have an ABR using a Kef B139 with voice coil for switched resistive damping to tune to the room, with a pair of Krell 250 monoblocks up them.

Cheers George 

Also realistically speaking 20hz wave length is 56.6 ft long you need a combination of at least that in all directions to eliminate room nodes. so that much bass in any room with out treatment is going to give you issues.

http://www.acousticfields.com/wavelengths-in-our-rooms/