In case you missed them at ISE 2018, Luxi brought over from USA the “world’s thinnest power amps.”
Only 1 inch (2.5 cm) tall, their AMP-902 is a 45W x 2 stereo power amp and their AMP-801 is a 80W mono 70/100V power amp. Each has 4 inputs including a mic input and a balanced line input.
Luxi Electronics Corp is a California-- based manufacturer of audio video products for professional and consumer markets-- and No. 1 HDMI cable supplier in the US market.