PA speakers, for a public address or PA system, are designed to provide highly amplified sound while preserving quality. These loudspeakers are best suited with a high quality amplifier and microphones for the best pro audio result. Avico announcement horn speakers are also available, suited for commercial use. The weatherproof model is specifically designed for outdoor event spaces. The Samson selection includes active loudspeakers, high performance passive loudspeakers, and active subwoofers, designed for professional musical performances. An active speaker means there is an amplifier system included, while passive models require an amplifier connection to produce audio. Active speakers may not provide as high quality amplification as a separate device. Sizes include 12 inches, 15 inches, and 18 inches.