Wnuanjun Full Range 2 Inch Speakers 15 W DIY Soundbar Boombox Unit Portable Radio 10 W 20 W 4 Ohm Speaker HiFi Bluetooth Speaker 55 mm (Size: 8 Ohm 10 W) : Amazon.de: Electronics & Photo
DIY 2.1 Walnut Soundbar and Subwoofer (active, w plans) : r/DIY
How to Make Your Own Soundbar : 8 Steps - Instructables