I have bought a new Smart TV but the sound is a bit disappointing. So I was wonder if using an RPi with some sort of on board amplifier would work; either normal sound to a speaker and Dolby. Is this a reasonable way to go... perhaps buying an external amplifier?
If you are using Kodi, you can follow this tutorial.
Fairly deep into the page, it mentions sound quality. You can use the HiFiBerry to provide better sound quality. I believe the HiFi will work with standard 5:1 surround sound. It functions both as the Pi's power source and as an on-board amplifier for really nice sound quality.
Hope that helps!