Once you've followed the instructions in this guide, you'll be able to experience Unreal Tournament 3 with accurate, 3D surround sound using only your stereo headphones. Sounds coming from in-front and behind will be distinctly different and even sounds coming from above or below will be clearly discernible. It will feel more like listening to reality than a video game.

Unreal Tournament 3 uses OpenAL for rendering audio. By default, the game will use the OpenAL driver that is distributed with a standard OpenAL installation, which happens to be a pretty shoddy implementation of OpenAL. We'll replace it with a better version called "OpenAL Soft" and configure it to enable HRTFs.

(If you're interested, there's information about what HRTFs are in the Further Reading section.)

• Download OpenAL Soft
  OpenAL Soft has a fairly modest-looking website, which you can find here[openal-soft.org]. For your convenience, here's a link straight to the download of the current version at the time of writing this guide:
  > Download OpenAL Soft 1.15.1[openal-soft.org]
  
  
• Unzip the archive
  
  
• Install OpenAL Soft
  You'll see a bunch of folders after unzipping the archive but we're only interested in the Win32 and Win64 folders. Installation is simply a matter of copying the DLL(s) into your Windows system folder(s).
  
  If you have 64-bit Windows:
  
  • Copy soft_oal.dll from the Win32 folder into C:\Windows\SysWOW64
    
  • Copy soft_oal.dll from the Win64 folder into C:\Windows\System32
  
  If you have 32-bit Windows:
  
  • Copy soft_oal.dll from the Win32 folder into C:\Windows\System32
  
  
• Enable HRTFs in OpenAL Soft
  We need to create a configuration file that will tell OpenAL Soft to use HRTFs.
  
  
  • Open Notepad
    
  • Type the following:
    
    hrtf = true
  • Click the File menu and Save As...
    
  • Type %APPDATA% and hit enter. It will automatically take you to the folder where we need to save this configuration file.
    
  • Change the Save as type drop-down list to say All files (*.*)
    
  • Type the File name as "alsoft.ini" and click Save.
  
  
• Configure UT3 to use OpenAL Soft
  You need to run UT3 at least once so that configuration files are created.
  
  
  • Open the My Documents folder in Windows Explorer.
    
  • From there, navigate to this sub-folder: my games\Unreal Tournament 3\UTGame\Config
    
  • Open UTEngine.ini with a text editor such as Notepad.
    
  • Find the section starting with [ALAudio.ALAudioDevice]
    
  • Under this section, change the DeviceName line to read:
    
    DeviceName=OpenAL Soft
  • Save the file.
  
  If you modify (or even look at) your options in the game, it will probably reset this tweak so make sure that you've already got everything set up the way you want it.
  
  
• Play UT3!
  To test that HRTFs are working, try creating a deathmatch game on DarkMatch with no bots. Move to the edge of the arena where the Shock Rifle spawns. There is a buzzing electrical device that moves passed this area of the map and you can listen to how is sounds as it passes you by.
  
  Also, near where the Armor Vest spawns, there's a staircase and some gas coming out of a nearby pipe. Shoot at the gas to set it alight. If you face the flames and look up and down, there should be distinct changes to the sound that wouldn't normally be present with the default OpenAL driver.
  
  Enjoy!

HRTF stands for Head-Related Transfer Function. In fairly layman's terms, it represents the changes that occur to a sound when it interacts with your ears and head before reaching your ear drum.

More on that here: Wikipedia: Head-related transfer function[en.wikipedia.org]



Products like Dolby Headphone, Razer Surround and Creative CMSS-3D provide a similar surround sound effect for headphones. The difference is that they use a pre-mixed 7.1 or 5.1 channel audio stream as their source input. This limits the accuracy of the sound localization to those 7 or 5 points in space. Additionally, they have no support for sounds coming from above or below because 7.1 and 5.1 systems do not have speakers above or below the listener.

OpenAL Soft is different. It doesn't receive a pre-mixed audio stream as its input because it is actually serving the function of the mixer itself. Therefore, all the precise coordinates of all the sounds in the game are available to OpenAL Soft.

CMSS-3D is an exception because it works with Creative's OpenAL driver and can have access to all the precise coordinates to provide fairly accurate sound localization. However, it does a terrible job of sounds coming from above and below, which is probably why they have a special option for turning the "Elevation Filter" on or off.

If you have a sound card or headphones that support Dolby Headphone or any other virtual surround sound system, you need to turn those features OFF when using OpenAL Soft.



Rapture3D is an excellent 3D audio system made by Blue Ripple Sound[www.blueripplesound.com] that also provides fantastic headphone surround sound (amongst many other cool things). I personally think that Rapture3D is the very best 3D audio system available but I decided to focus this guide on OpenAL Soft because Rapture3D is not free. It costs about the same as a full-priced game and I highly recommend it if you're into 3D audio.

Rapture3D can be used with games that use OpenAL in the same way that you use OpenAL Soft. However, it is recommended that you follow the instructions on their Compatible Games[blueripplesound.com] page instead.



I know, right? It's a pity that most games don't use OpenAL and don't provide any built in HRTFs for headphone users. Read my rant on this matter on my blog:

> I Want HRTFs In My Games![matthewkerswill.com]



The default OpenAL driver actually has very iffy support for surround sound speakers. Users of 7.1 and 5.1 speakers can also benefit from using OpenAL Soft instead of the default OpenAL driver. You won't need to enable HRTFs for speakers, though.



Unfortunately, in the majority of cases, it won't work. Most developers tend not to use the OpenAL implementation and instead use XAudio2 or some other audio middleware. Some examples of Unreal Engine 3 games that should work are: Alien Breed series, America's Army 3, Mass Effect and Mirror's Edge.