Boston Acoustics HS 40MDNT Midnight (Ea) Horizon Series 2-Way Loudspeaker (Discontinued by Manufacturer) 4-1/2 woofers and 1 soft dome tweeters Recommended Amplifier Power - 10-100 watts Frequency Response (3dB) - 86Hz-25kHz Bass Unit - 4-1/2 (114mm) DCD with Phase Plugs and MagnaGuard Crossover Frequency - 2400Hz