 Acoustic suspension was invented in 1954 by Edgar Villchur, and brought to commercial production by Villchur and Henry Kloss with the founding of Acoustic Research in Cambridge, Massachusetts Speaker cabinets with acoustic suspension can provide well controlled bass response, especially in comparison with an equivalently-sized speaker enclosure that has a bass reflex port or vent.The bass vent boosts low-end output, but at the tradeoff of introducing phase delay and accuracy problems.Sealed boxes are generally less efficient than a reflex cabinet, so a sealed box speaker cabinet will need more electrical power to deliver the same amount of acoustic bass output.