What you see is what you hear

When you’re playing a game requiring fast reflexes, the time it takes between hearing a sound and seeing the effect it has on your player character can change the course of the game! EPOS engineers dive deep to minimize latency.

Experienced gamers – especially those who play competitively will tell you that the biggest problems that interfere with their enjoyment are often down to a characteristic of systems known as “latency” – the time delay between the moment something is triggered and the moment it is actually observed happening.

For example, every internet connection suffers from latency – the amount of time it takes for a packet of information to be sent from one place and received in another. Game controllers may also suffer from latency – the amount of time between pressing a button and seeing the action occur on screen. There’s even latency in the screens we connect to, especially if they don’t have a low-latency “game mode” – the TV may have its own image processing systems that introduce a delay to the signal.

Audio systems are no different, and wireless connections are notorious for suffering from latency. Classic Bluetooth audio connections have a latency of up to 200 milliseconds (a fifth of a second). Combine this with the other small processing delays in the chain – the button press getting to the game, the game triggering the audio, the audio getting to the Bluetooth receiver – it means there can be a very noticeable delay between what you see (the flash) and what you hear (the explosion).




Illustration: From visual to auditory input when gaming.



Latency doesn’t matter when you’re listening to non-interactive audio – so Bluetooth headphones may be great for your favorite podcast despite their high latency. For linear video like a movie, you can introduce a delay to the images to synchronize with the audio reaching your ears. The principle is simple – if you know what’s coming next, then you can compensate for any delays in the chain. But playing a game relies on unpredictable control inputs, so it’s not possible to delay the signal to solve the problem. This is why reducing latency for wireless headsets is vital to maintain immersion in the game.

At EPOS, we have spent a great deal of Research and Development time on reducing audio latency in our wireless systems. It begins with selecting the most suitable chipsets / components and audio codecs. (A codec is the computer program that encodes the audio ready for transmission and decodes it at the other end).

There may be engineering trade-offs required. For example, highly efficient codecs that encode, transmit and decode quickly may require lots of lossy compression that reduces the audio quality to unacceptably low levels. Or there may be a highly efficient codec that transmits in much higher audio quality, but it requires a more powerful chipset that is both more expensive and consumes more power – which may vastly reduce the battery life of the headset. Let’s face it, if it was a simple problem to solve, every headset would have low latency, long battery life and high-fidelity audio, but that is not the case.

The EPOS GSP 370 wireless headset is a great example of low-latency sound in wireless gaming – the latency it introduces to the audio chain is barely perceptible. We wanted to design a wireless headset that was as close as possible to a wired one in performance while maintaining an exceptionally long battery life of up to 100 hours of continuous use. We set ourselves the design challenge and achieved the right balance for the gamer who simply wants to “cut the wire”.

Our commitment to continuous improvement is empowered by our decision to equip our wireless headsets and dongles with reprogrammable firmware. This enables our team to pass on the benefits of our R&D to existing as well as future consumers.

Building products that sound great is never easy; and achieving excellence in game audio – and that includes a focus on latency – is even harder. At EPOS, we understand what gamers need and have the engineering skills necessary to deliver against those requirements without compromise.

A great example of ingenuity in our engineering is found in the GTW 270 Hybrid wireless gaming earbuds. They can operate using Bluetooth for non-interactive audio functions like listening to podcasts or making phone calls; but they are paired with a tiny USB-C dongle that can be plugged into an Android phone or Nintendo Switch portable console for low latency gaming on the go. While they can’t quite achieve the lowest levels of latency enjoyed by the full sized 370 headset, by utilizing a specialist power-efficient codec called aptX™ Low Latency, EPOS can offer class-leading low latency in earbud form factor while maintaining full Bluetooth compatibility.