The frequency response of the one π loudspeaker is 70Hz to 20kHz, +/-3dB. The two π is 65Hz to 20kHz and the tower two π is 40Hz to 20kHz. Each has nice smooth rolloff, slightly overdamped, so room lift brings up the bottom end without making them sound boomy.Kits include the speaker drivers, the connector panel, hook up wires, "π" logo decal and a printed copy of the plans. For larger speakers that incorporate a compression tweeter and crossover network, kits also include the crossover, Zobel woofer damper, and all cable assemblies are completed and ready to install. Every kit containing a compression driver also includes the horn flare and the bolts to mount the driver to the horn.