This product for sale is the SUBWOOFER ONLY.... unfortunately you will need the other speakers for this woofer to work.   This is a perfect sub if you have the other speakers... so if you have this system and your sub is bad, then this would get you back up and running.

Logitech Z-640 specifications

Below you will find the product specifications and the manual specifications of the Logitech Z-640.

The Logitech Z-640 speaker is a wired, 5.1 channel audio output device designed to enhance your audio experience. With a total speaker power of 71.2 W, it provides a high-quality sound output. Featuring a subwoofer RMS power of 25.7 W, the Z-640 delivers deep bass that adds richness and depth to your audio. The satellite speakers have a combined RMS power of 45.5 W, ensuring clear and balanced sound reproduction. The speaker is bundled with full product support software, allowing for easy installation and troubleshooting. The connectivity technology of the Logitech Z-640 is wired, meaning it connects to your audio source via cables for a reliable connection. With a signal-to-noise ratio (SNR) of 75 dB, this speaker minimizes unwanted background noise, resulting in clear and crisp audio output. Constructed with premium materials, the Z-640 is built to last and guarantees durability over time. Overall, the Logitech Z-640 speaker is designed to provide high-quality audio output, with deep bass and balanced sound reproduction. Whether you're listening to music, watching movies, or playing games, this speaker system aims to enhance your audio experience with reliable performance and clear sound.