A soundbar and subwoofer cost the same wherever they sit, but they sound very different depending on where you put them. Most of it comes down to two ideas: bass piles up against walls and corners, and a bar can only fill the room if nothing blocks it. Try the spots below, then read the reasons.

Try the four spots

This is a top-down view of a living room: the TV wall at the top, the sofa at the bottom. Move the subwoofer and the soundbar and read what usually happens. These are rules of thumb from setup guides, not measurements. Your room has the last word.

Why corners boom

Low notes are long waves, and a wall or corner reinforces them. Put a subwoofer in a corner and you get more bass, but setup guides, including Homes & Gardens and Polk Audio, warn that it tends to come out boomy and less defined. Polk suggests nudging a subwoofer that sits midway between two walls by a few inches. Homes & Gardens suggests keeping it a couple of feet (around 60 cm) from the nearest corner. Don't put it on the sofa either, because cushions soak up bass.

The crawl test

Subwoofer position matters less than for other speakers, but there is a cheap trick to find a good spot. It looks silly and it works.

1. Put the subwoofer on your seat, where your ears will be.
2. Play a track or scene with steady, heavy bass.
3. Crawl around the room at ear height and listen for where the bass sounds fullest and cleanest.
4. Put the subwoofer on that spot, then fine-tune its volume (and crossover or phase, if it has them) so it blends with the bar.

If the bass is strong in one seat and thin in the next, a second subwoofer is the usual fix. Most soundbar systems come with one, so for most rooms the crawl is the whole job.

Where the bar goes

Centre it under the TV, ideally at the middle of the screen's width, so dialogue seems to come from the picture. Keep the front clear of shelves, plants and cabinet doors. If the bar has upward-firing speakers for Dolby Atmos, keep the space above it empty too. Polk says those work best under flat, hard ceilings roughly 7.5 to 12 feet (around 2.3 to 3.7 m) high, and that acoustic tiles soak up the overhead sound. Your manual will list the maker's own limits, and some bars skip the upward drivers altogether.

Not sure what the numbers on the box mean? Read what 2.0, 3.1.2 and 5.1.2 really mean, then answer four questions to find the right size for your room. If speech is the problem, start with why dialogue gets lost on your TV.