If your wireless wall speakers have Bluetooth technology, you will be able to reach up to 10 metres before experiencing audio cutting out, depending on your smart device and any obstacles between your device and the speakers.
On the other hand, if you have WiFi wall speakers, the range spans across the entirety of your home. As long as your smart device and the speakers are both connected to the same WiFi network, you will be able to control the audio from anywhere in the house.