By Dylan Rhodes posted Apr 06th 2012
With the launch of the Vengeance 2000 wireless gaming headset, I’d like to take a look at some technology in the Vengeance 2000 that’s been in our headsets since we launched our first model, the HS1, a year and a half ago: 50mm drivers.
“Driver,” in this context, doesn’t refer to software drivers, but rather, the “speakers” within the earcups. They each have a diameter of 50mm. We created the HS1 because we just weren’t impressed with the majority of gaming headsets on the market at the time, and most of them used 40mm drivers or even smaller drivers in some cases.
A larger-diameter driver has the capacity to sound better than a smaller driver – that’s intuitive to many people. In this post, I’ll explain why.
It’s also intuitive that a larger driver is capable of producing lower-frequency sounds than smaller drivers. We’re all familiar with the speaker designs found in home audio: subwoofers have large diameters; midrange drivers and tweeters are progressively smaller. The physics are easy to understand even for people with a passing knowledge of audio: large drivers resonate with longer periods, and that’s how they produce low-frequency bass.
That’s more or less correct. But, it’s just a small part of the story. It’s true that the HS1, and HS1A, and the Vengeance 1300, 1500, and 2000 can produce some satisfyingly deep lows – down to 20Hz -- thanks to the 50mm drivers. But it’s about clarity, detail, and sonic accuracy as much as it is about getting that visceral bass experience.
Any device that reproduces sound – whether it’s a headset with one driver per channel, a two-way studio monitor, or a multi-driver home theatre speaker system – will have a frequency response curve that, when controlled for a maximum level of distortion, will drop off at the low and high ends where the speaker (or speaker system) hits its limit.
The maximum volume, measured in decibels, that the system can produce without hitting a set distortion threshold drops severely. When you get to the limits, you must pick one: lower volume, or higher distortion.
What we found when testing many gaming headsets was that they’re able to reach the lower range of the audio spectrum only by overloading the drivers, and adding the distortion. That distortion might not be immediately obvious, like the sort you hear from an overdriven guitar amp, but subtle distortion can mask important audio information and deliver a listening experience that’s just unsatisfying, even if you can’t put your finger on exactly why.
The issue of detailed audio isn’t just at the low end of the spectrum. Larger drivers can produce more audio detail, period. The simple physics go like this: a larger diameter driver has more surface area, and can produce more sound at once. In this context, audio engineers describe it in units of acoustic power or sound power, which is expressed in watts.
It’s first calculated by measuring the sound intensity, which is itself the product of air pressure and velocity. The sound intensity is multiplied by the area, and that’s why a larger driver will have higher sound power. Since it’s a multiplier, a headset with 50mm drivers can have significantly higher sound power than an ordinary gaming headset with 40mm drivers, even though both get the same line-level voltage from the PC.
But the goal wasn’t to design a louder headset; rather, a headset that can deliver more sound. That’s not the same thing!
You see, gaming audio is very complex. You’ll have music and ambient environmental sounds, plus the sounds made by NPCs, your teammates, and opponents. Then there’s the audio that you’re generating when you fire your weapon. That’s a lot of layered 44 kHz waveforms. On top of that, you have VOIP chatter, and many audio effects are put through dynamic environmental processing for realism that’s necessary not only for a compelling experience, but to give you the environmental information you need to be competitive. And on a multi-channel headset like the Vengeance 2000, there are the HRTF, duplex, and crosstalk cancellation algorithms applied to the multi-channel audio sent by your PC so that it’s delivered to your head with accurate positional audio intact.
That’s a lot of work for the drivers to do. And that’s what sound power delivers: more sound. More power to accurately render each of those waveforms for a whole that’s greater than the sum of its parts.
Play the same game with a headset that uses 40mm drivers, and something will be lost when everything starts happening all at once. You’ll still hear all those sounds, but you’ll probably miss out on the details. Again, it’s not distortion similar to an overdriven guitar amp; you won’t even know what you’re missing, unless you’ve also played the game on a Vengeance headset. Many people who’ve gamed using lower-quality audio gear hear that wall of indistinguishable audio noise when the action gets intense, and they think that’s normal. They simply haven’t heard gaming audio the way it can be with a well-designed headset.
If all it means is less audio enjoyment, then the only obvious effect might be that you’ll take off the headsets a little sooner and maybe even go outside and bask in that big flaming ball in the sky. But if it detracts from the environmental audio that gives you a competitive edge, that 1cm delta in the driver diameter may mean the difference between winning and losing.