An HDMI audio splitter is a device that allows you to send audio signals from a single HDMI source to multiple audio outputs. This is useful when you want to connect one HDMI device, like a Blu-ray player or gaming console, to different audio systems, such as a soundbar or home theater system. These splitters work by taking the audio signal from the HDMI source and distributing it to various outputs without losing quality. They are commonly used in setups where high-quality sound is essential, ensuring that you can enjoy your media through different audio devices simultaneously.