http://developer.creative.com/welcome.asp

找eax sdk的下载居然费了好长时间， 直接goole eax sdk不就行了嘛！
关键是不知道有sdk，哈哈！

        sdk, introduction, programmer's guide 都要register了才能看到，毛！注册就注册吧，还要填一份pdf文档，好像要用信件或者传真发过去，居然不让用emai， 我靠！估计是要保密吧，不能随便什么人都能看到sdk,拿到的人要遵守保密协议！

看看这个吧！
FAQ:

 What is EAX?
How do I get EAX into my game/application?
Where can I find a comprehensive list of games that support EAX technology?
 My game uses Miles, does that mean I can't use EAX (3.0 / 4.0)?
 Is EAX a complete audio engine?
What is EAX ADVANCED HD?
 What is the difference between EAX ADVANCED HD and EAX 3.0/4.0/5.0?
What is in the EAX SDK?
Why can't I access / download the EAX 3.0/4.0/5.0 SDK?
 What soundcards support EAX 3.0/4.0/5.0?

What is EAX?Creative's EAX or Environmental Audio Extensions is a technology that adds an extra level of realism to the audio in a game. From claustrophobic caves to wide open plains, EAX adds the appropriate reverberation to suit the environment. This means that a game developer need only record a sound effect once and it will sound perfect no matter what situation the player gets into!

How do I get EAX into my game/application?Navigate to the Games > Dev Kits & Tools > EAX section to browse through the available EAX Software Development Kits, Application Guides, and Documentation. The Software Development Kit will guide you through the process of adding EAX technology support to your game / application.

You may also wish to visit the Games > Legacy Technology section to browse through older versions of EAX.

Where can I find a comprehensive list of games that support EAX technology?There are many games on the shelves today that support every level of EAX technology. For a full list of game titles, please visit Soundblaster.com.

My game uses Miles, does that mean I can't use EAX (3.0 / 4.0)?Not at all, the Miles Sound System now has full support for EAX 3.0 & 4.0.

Is EAX a complete audio engine?No, EAX is an extension to the existing audio engines DirectSound and OpenAL.

What is EAX ADVANCED HD?EAX Advanced HD represents the latest technology in realistic audio. Using a statistically modeled reverb, EAX can be added to any game to create a a realistic ambience. For more information please visit Soundblaster.com.

What is the difference between EAX ADVANCED HD and EAX 3.0/4.0/5.0?EAX Advanced HD is used to describe any version of EAX from 3.0 onward.

What is in the EAX SDK?All of the EAX Software Development Kits contain all the files you need to add EAX to your game as well as code samples and a comprehensive API guide.

Why can't I access / download the EAX 3.0/4.0/5.0 SDK?Because EAX 3.0/4.0/5.0 programming information is confidential, access can only be granted to registered developers.

If you would like to join the Digital Media Relations program and register your company, please navigate back to the home page, and click on the Register Now! button to download an application form.

If your company is already registered, but you do not have a login ID, please contact your account manager to request access.

What soundcards support EAX 3.0/4.0/5.0?EAX 3.0/4.0 is supported by Creative's Sound Blaster Audigy, Audigy 2, Audigy 2 ZS, and Sound Blaster X-Fi Series sound cards.

EAX 5.0 is supported only by Creative's Sound Blaster X-Fi Series sound cards.