If you're designing a set of headphones, and you want the fullest, most accurate sound, normally you'd try and wedge larger and bigger speakers into your headphones so you can fully replicate each of the channels in 7.1 surround sound.
But what if most games don't actually support 7.1 surround sound, or the support isn't good? That's what ASUS found during the production of their latest headsets, so they made a rather interesting call.
The ROG Theta and Theta Electret is ASUS's attempt to deepen their product stack in gaming audio. The pitch is pretty straightforward: you should get good surround sound with 7.1 channel headphones these days, but you don't. And the reason behind that is because most games don't actually support the bass—that's the .1 in 7.1 channel—properly, and their engineers found that sometimes 7.1 sound isn't even supported at all.
That's especially true with older games, but it's also true for a lot of gamers that don't configure their Windows settings to match their headphones. So rather than having a separate bass driver inside their new Theta headphones, ROG got rid of it entirely, instead virtually assigning the bass to be managed by the front, centre, side and rear speakers inside each earcup.
The end result allows the other drivers to be 10mm bigger, although bigger drivers don't necessarily result in better sound (although they can generate more sound). That's down to having better components, and for that ASUS has the Theta Electret, a headset that combines electret and dynamic drivers.
Electret drivers differ from standard dynamic drivers (which I've covered a bit more here) in a lot of headphones by using a thin membrane wedged between two metal plates that has a permanent static charge throughout. (Electrostatic drivers are very similar, but their static charge is provided by an external source, which isn't very practical for a gaming headset.)
To resolve any issues with the headphones being weaker at lower frequencies, ASUS have combined a dynamic bass driver to handle frequencies between 20 and 7500Hz. The dynamic driver slowly rolls off to the electret drivers beyond that point.
Dual-driver headphones are pretty rare in the audio world. The reason why you don't see them much is because they're difficult to manufacture: it's surprisingly difficult to get both the drivers playing at the right levels, and managing the handoff between the dynamic driver and the electrec driver badly can interfere with the sound. Making sure the two drivers don't resonate against each other isn't easy either. More prominent audio brands have tried and failed with their dual-driver headphones, so it's kind of fascinating to see ASUS give it a crack.
Local pricing and availability on the Theta and Theta Electret weren't available at the time of writing. It'll definitely be interesting to see if ASUS tries to appeal to audiophiles that are gamers, a market that's only getting more crowded.
The author travelled to Computex 2019 as a guest of ASUS.