KJ04 is a passive speaker and requires an amplifier or receiver to produce sound. It cannot be connected directly to a turntable, computer, or phone. The speaker uses a 1 inch tweeter allowing for more room at the high-end. For bass, a 3-inch driver is used for smooth, rich, low frequency sound. All provides more accurate reproductions of sound with smooth treble & vocal clarity with low distortion. The KJ04 is designed to fit perfectly on shelf, desktops or wall mountable. Its well-balanced sound signature and vocal clarity are a great fit with a wide range of usage scenarios, from background music to home theater. Amplifier is required and not included. Speaker wire is required. Material: Wooden body Bass: 3 inch Treble: 1 inch Impedance: 6 Ohm Rated Power: 15W Sound Pressure Level: 75dB Frequency response: 65Hz - 20KHz Size: 4.72 inch x 5.51 inch x 7.28 inch Weight: 1040g