Logitech today announced the Z-5450 Digital speakers, which it says are the world’s first THX-certified 5.1 speaker system with digital wireless dual rear speakers. Each of the independent rear speakers can be placed anywhere within 28 feet of the speaker system control center, requiring only a power outlet. The system also offers 315 watts of power. The Logitech Z-5450 Digital speakers will be available in the US this month for a suggested retail price of US$499.99. Logitech also extended its Z-series family of speakers to include the new Logitech Z-4 speaker system, a 2.1 system with a new three-driver satellite design. The speakers are available in black and white and will be available in the US and in Europe in October for $99.99.