The Wireless DJ is rated to be able to transmit at a range of up to 165 feet (50 meters). For most of this review, I placed the transmitter and receiver one room apart, about 15 feet away, and the system performed flawlessly. However, to test its range, I moved the receiver to another room about 45-50 feet away from the transmitter - this put 3 indoor walls between the PC and the stereo.
The sound became jumpy when I did this, so I adjusted the direction that the transmitter and the receiver were facing as recommended by the manual, and then placed them at the limit of their cords away from any other electronic devices. I also shut off my wireless router and went so far as to shut off my Bluetooth-enabled cell phone, to try to reduce all possible interference sources. After all that, the signal appeared to gain a little strength, but I wasn't able to completely eliminate the interference. (In fairness, one other factor that I wasn't able to control is the high wireless traffic in my building - I can usually pick up 5 or 6 strong wireless connections at any given time in my apartment...)
The manual recommends that the wireless DJ be placed well away from any wireless networking devices and I did notice a slight increase in performance when I shut my own router off. I talked to Logitech about this problem and they stated that the Wi-Fi traffic could definitely play a part in decreasing the overall range of the wireless DJ system. Those who live in apartments with the potential for a situation similar to mine should keep in mind that they might not have as much flexibility when it comes to range.