In Memory of EAX

Remember EAX? I wouldn’t be surprised if you haven’t heard of it at all or only have a vague idea of what it was. There was a time when PC gamers upgraded their sound cards much in the same way as with graphics cards, resulting in a similar level of improvement in presentation aurally as graphics cards do visually. During 1998-2008 hundreds of PC games adopted EAX and hardly any videos exist of games with it enabled. The lack of recorded content provoked me to revisit all these old titles and see if EAX was as significant as I had always believed it to be. What I discovered was that the quality of the sound in these older titles varies a lot more than I expected. Some sound quite bad by today’s standards while others can stand toe to toe with the very best games released last year. To easiest experience the difference EAX makes for these titles I prepared a short video montage of before-after clips. The difference is not subtle as even the worst speakers or headphones should amply demonstrate the dramatic change in sound EAX makes.

Having acoustic effects in games is important even if you might not pay any attention to them. If the sound doesn’t match what you’re seeing you will subconsciously sense that something is wrong, or you just won’t connect with what you’re seeing. That’s why most games go to great lengths to have different acoustic environments to create the correct sense of space even if the effect is often subtle. This wasn’t the case before the first EAX sound card came out, however.

Back in 1998 Creative Labs and Aureal Semiconductor were about to change the sound card market. For the first time, developers could use hardware accelerated DSP effects for sound which allowed significantly higher quality acoustic effects than had ever been heard before in games. Aureal was sued by Creative Labs and the lawsuit caused Aureal to go bankrupt.  The fact that Aureal shut down because of the Creative Labs lawsuit caused many users to hold a grudge against Creative, and would be one of many PR problems Creative would deal with over the years. Incompatible motherboards and drivers that caused blue screens were among the problems users could run into if they wanted to enjoy the full audio experience that PC games could offer. The problems even persist to this day as I personally ran into blue screens caused by the sound card while trying to capture footage from Quake 4.

Given CPU limitations and the lack of middleware alternatives meant using EAX to enhance the audio experience made a lot of sense. With a minimal performance drop you got all sorts of enhancements and as sound cards improved old titles sounded better with no extra effort on the part of developers. For example, when games like Jedi Knight and Thief 1 came out there were no 7.1 sound cards or even 5.1 for that matter. Thanks to hardware acceleration the work of making sure a sound was sent to the correct speaker was handled by the sound card.  By not having the game handle this work meant that older titles could scale up to 7.1, 10.1 or any arbitrary number of speakers if someone would make such a card. Up until around 2004 it was standard for games to only provide stereo sound in software mode and surround support relied entirely on hardware acceleration.

This situation changed when Doom 3 and Half-Life 2 came out which were arguably the most anticipated game releases of all time apart from Duke Nukem Forever. Neither of these games used hardware acceleration and tried to elevate software sound to a new level in their own ways. Half-Life 2 was the most successful at this and had sound post processing effects that were about on par with the earliest versions of EAX. While it was still not as good as what EAX could do at the time it was still a big step forward as a developer using the Source Engine knew that all players would get the same experience and didn’t have to worry about how the game would sound with or without hardware acceleration. The move away from EAX to software solutions would take a few more years to happen however for most titles.

A high profile EAX title that came out the same year as Half-Life 2 was Thief 3: Deadly ShadowsThief is a series that relied on sound more than almost any other games as they discouraged combat. Fighting against the weakest enemies would end in death or severe injury, so hearing where the AI was and what it was thinking was of utmost importance. All the games in the series used EAX to great effect as it brought the old castles, streets and caves to life with appropriate echoes, and due to the slow pace of the games you had plenty of time to sit and listen to the effects. The more subtle advantages of EAX over what the software sound of Half-Life 2 provided such as transitions between different echoes, multiple kinds of echoes at the same time were easy to appreciate in a slower game like Thief 3. My next clip is from the first mission and I picked a great hall with an obvious echo effect to showcase what EAX did for it. In a game where the amount of noise you’re making is integral to the game mechanics having effects like the ones in the clip become more important than just immersion. Hearing how much the noise is amplified by the walls makes big room feel dangerous as you become afraid of how much sound you make.

The sound card monopoly by Creative was broken when Asus entered the market in 2008 with their Xonar line of cards. The ill will built up over many years and the promised EAX emulation offered by Asus made many users switch. It didn’t matter that the EAX emulation turned out to be largely non-functional or buggy as Asus quickly got a reputation for giving a higher audio fidelity thanks to quality components.  Asustiming couldn’t have been better as developers were moving away completely from hardware acceleration to software solutions for the same effects.

Today, EAX is dead. With the increased emphasis on consoles and the dwindling sales of CreativeLabs cards it just didn’t make sense to use EAX over software sound anymore. In 2008 the last major EAX titles were released and after that all support from developers died. The current multicore CPUs makes it easy to add all sorts of cool effects to the sound in high quality without any major performance drop. This is good news for audio enthusiasts as software solutions really can sound better than anything before. It took a while, but I feel that software sound caught up with EAX in 2007 with the release of Crysis. It had all the subtle acoustic effects I demand from an immersive game when moving from beach to woods to mountain areas. It also had full support for up to 7.1. Most people might not see the point of that, but the PC is all about being able to configure the gaming experience to any level you want whether it be 7.1 sound or 5+ monitors for extreme widescreen experiences. Console games usually only have support for stereo and 5.1 and that is true for most games today, but there are still some games that support any configuration Windows does and that’s the way it should be.

An example of how good sound can be today using software solutions is Metro 2033 which on PC uses “wave tracing” which is the sound equivalent to ray tracing. In the video the player objective is to stop the endless stream of monsters into the metro station by caving in the tunnels they use. The few remaining settlers fight off the endless stream and as you move away from them in order to locate the tunnels the sound of gun fire keeps changing based on your distance from them just as you’d expect. The way the sound changes is done in real time and is not a pre-baked ambient sample. Thanks to the advanced audio tech being used it adds tremendously to the immersion of the game as the effect it present in every map of the game.

EAX played an important role for ten years, but now that it’s gone I don’t think anyone will miss it. Being forced to buy extra sound cards from a specific manufacturer in order to make sure the audio experience isn’t compromised isn’t something anyone would want. Let’s not forget it though because when the day comes that you want to experience these older titles knowledge of EAX and having hardware that supports it becomes critical.

Peter HasselströmComment