When you're trapped in a jungle firefight, Dolby Atmos goes beyond surround sound to ensure that choppers roar overhead rather than just around your lounge room.

As big arse televisions get more and more affordable it's easy to forget that blockbuster movies aren't just about a great picture. Immersive and engrossing sound really helps bring a movie to life, so it's important not to skimp on your sound system.

Surround sound has come a long way in the 40 years since Darth Vader's Imperial Star Destroyer flew in over the camera while chasing Princess Leia – thrilling seventies cinema goers with the rumbling rear speakers of the new four-channel Dolby Stereo.

Movie sound has evolved over the years to add more speakers, but now Dolby Atmos takes a new approach to filling the room with sound.

Traditional surround sound is mixed for a certain number of channels, for example Dolby Digital offers 5.1-channel sound which splits the audio between two front speakers, a centre speaker and two rears – with a subwoofer making up the 0.1 to add more punch to the low-end.

Dolby Atmos works differently because it's object-based rather than channel-based. This lets movie makers create a background soundtrack and then place objects on a three-dimensional sound stage – like an incoming chopper. In your lounge room, your home entertainment gear decides exactly where to send the sound of that chopper, allowing for how many speakers you have spread around the room.

This means Dolby Atmos works in a two-speaker lounge room, a 192-speaker cinema and everything in between. We have a few Atmos-capable cinemas in Australia, plus you get Atmos soundtracks on some Ultra HD Blu-ray discs (unfortunately Atmos tends to be missing on Blu-ray discs sold in Australia).

Now Dolby Atmos is coming to Netflix, although only on a handful of Netflix Original titles at first, starting with Okja. Hopefully Netflix will expand on this, as dozens of blockbuster movies have included Atmos soundtracks over the last few years. Initially, Dolby Atmos on Netflix only works with the Xbox One, One S and 2017 LG OLED TVs, but that should also expand over time.

One of the benefits of Dolby Atmos is that it adds a sense of height to your surround sound, so in a storm the thunder and rain sound like they're above you, not just around you. Likewise choppers seem to roar overhead rather than to the side.

For the full Dolby Atmos effect you want speakers in the ceiling but you can also appreciate the difference when using upwards firing speakers which bounce sound off the ceiling.

That sense of height still comes through even if you only have a soundbar with upward-firing speakers like LG's SJ9, rather than a full surround sound system which not everyone can justify or even fit in their lounge room. Those upward-firing speakers help any movie soundtrack really fill the room, but there's a subtle improvement when you switch to a movie with an Atmos soundtrack – admittedly you need an ear for detail to appreciate the difference.

How many speakers do you have in your lounge room? Are you keen to make the leap to Dolby Atmos?