Its a 4 way system with TAD 2001 in Autotech Poland made JMLC 1400 horns, then TAD 4001 in JMLC 270, then dual Jbl 2220 alnico fifteens in selfdesigned Front Loaded Horns then EighteenSound 21" in 12 feet 1 fold subhorn with pressure released rear chamber. Subhorn actively lowpassed at 75 and driven by HOLTON/Aussieamplifiers 350 watt Toer of Power. sensitivity 92db@20hz! Rest of system passively X/O at 600 and 8K. Nortcreek 8 awg ibductors and Mundorf silver in oil caps. Sens from 75-22K= 112 dB. 75-22K driven by all out choke input,interstaged 300B