Designed by Siegfried Linkwitz: Google Audio Artistry Vivaldi review in Audio Adventure and see in what high esteem these unique, beautiful models are held.No cabinet, , but a handsome black mesh cloth allowing the frame to appear enclosed, w. lovely real rosewood strips running down each side,Each 'enclosure/frame' contains 2 8' midranges w/ silk dome tweeter in between, and two 12' woofers back to back; all except tweeter in full dipole radiation. The dipole woofers' cancellation of output at sides of speaker virtually eliminate room boom; true musical bass notes and sounds come from these Vivaldi's, and it's a revelation that also allows for wide open, natural uncolored midrange; realistic voice quality, and 3-D soundstage well beyond any monopole box speaker Linkwitz filter network from the master. The beautiful speakers sound like Quads that play loud and have amazing, lifelike bass, no kidding! Owner has loved them, never plays loud music, physical condition near mint. Local buyer, pickup or meet conveniently. Cash or bank check only. A giveaway price for a far more realistic loudspeaker than 90% of today's high-priced spread; someone will be super -lucky to get these. And they are lovely.