It depends on your priorities. All of these connections will ultimately allow you to play music from your device wirelessly, but there are pros and cons to each of them that might sway your decision. For a start, what device you own might make a difference. Bluetooth is pretty universal, and also arguably a lot more straightforward.
Google’s Chromecast and Apple’s AirPlay both work using your home Wi-Fi network, whereas Bluetooth is a different, standalone technology. It works via a direct connection between wherever you have your music stored – such as your phone or laptop – and your speaker. That means Bluetooth is the thing to use outside of the house, as it isn’t reliant on any other technology.
However, if music quality is important to you, Wi-Fi speakers are better than Bluetooth. Chromecast pips AirPlay here, as it supports high resolution music (up to 24-bit/192kHz), while Apple’s tech only supports playback to CD quality (16-bit/44.1kHz). Bluetooth is currently limited to around the same, but it will depend on your equipment as to whether it can manage it.
Other things to consider – Wi-Fi speakers generally have better range and also allow for multi-room playback with other compatible speakers in your home. Bluetooth is generally limited to a single device, though some companies are now allowing you to ‘daisy chain’ speakers together to play the same song across several speakers. Wi-Fi multi-room is more flexible – you can play different songs on different speakers.
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