Meet BRAVEN Fuse: a smart gadget that lets you mix and fade multiple audio streams. It links to smartphones and speakers via Bluetooth and comes with onboard controls, allowing you to change source volume and other settings. The device is lightweight and compact. It measures less than 5″ long and comes with a 1200 mAh rechargeable battery that lasts up to 7 hours. The BRAVEN Fuse is available for under $100.