Many smaller TVs come with poor sounding speakers which sound similar to laptop speakers. However, most smaller TVs also have a 3.5mm head phone jacks on the side which let you easily plug in a pair of head phones, or speakers which uses a 3.5mm jack. This means you can buy a pair of 2.1 speakers like Logitech S220 2.1 Speaker System with Subwoofer which are mainly use for computers and portable music players for your TV. In Some cases, you may need to buy a Y-connector like the one listed below to connect your RCA audio output plugs to your TV RCA out, so you can convert it to a 3.5mm plug to plug your speakers into the TV.
By having a sub woofer, which is the biggest speaker, the bass would be better sounding. The left and right speakers for your new 2.1 sound system also sound better then the cheap inexpensive speakers on your smaller TV. This means you would experience more realistic and louder sounding sound on the Logitech S220 2.1 Speaker System with Subwoofer compared to using the built-in sound on budget home TV speakers which are not as rich sounding as Logitech's 2.1 speakers.