A classic stereo solution for improving TV sound: here, instead of a soundbar, you connect the 25 cm wide integrated amplifier with the TV, and two speakers to its terminals. The audio signal can be fed in via S/PDIF optical or coax or analog via Cinch. The TV-50 receives music from a smartphone wirelessly via Bluetooth. If required, headphones and an active subwoofer can also be connected. The output power is specified by the manufacturer as 2x50 Watt.
Small integrated amp for 150€
Dynavox TV-50: Amp for TV Sound
The compact device has analog and digital inputs and can even receive Bluetooth.