Not every studio has the resources to dedicate several members of staff to the development of a bespoke audio engine for their latest game – especially when it’s easy to dismiss the multi-layered intricacies of top-notch audio as being too grand for your project. But with flexible licensing agreements available for smaller-scale XBLA, PSN or WiiWare projects, and even free versions of some available for hobbyist or independent developers, with the right audio middleware every game can sound as good as it looks.

But which one is the right one for you? We’ve rounded up the four leading audio engines from across the world to give you a quick overview of each one’s particular strengths.

CRI Audio

CRI’s latest audio engine is a next-gen cross-platform audio engine for PS3, Xbox 360, PC and Wii, and promises the exact same output on each platform.

The real draw is that the tech is a full audio pipeline – the powerful tool suite gives sound designers the ability to design interactive and intelligent random sounds such as footsteps and gunfire to avoid repetition, in a format that can quickly be taken and manipulated by programmers based on real-time factors.

The runtime is optimised to all of the target platforms – on the PS3, digital signal processing is carried out on an SPU; a hundred simultaneous sounds can be processed on a single Xbox 360 CPU core; and the Wii version takes advantage of the native hardware acceleration.

Finally, being based on CRI’s hugely popular ADX middleware brings with it comprehensive streaming and buffering support even while other level assets are being loaded.

The company also offers a DS-tailored audio engine, CRI Vibe, a streaming audio toolkit based again on its ADX audio-compression codec. The tool can compress to an extent that up to nine hours of compressed data can be stored on a 512Mbit DS cartridge, at a compression rate better than the stock DS codec. Not only does this compression mean that more can be stored on a cart, it also means that games can be shrunk to fit on smaller capacity cards, thereby reducing production costs.
www.cri-mw.com

FMOD

The ever-popular FMOD continues to woo developers of the hottest triple-A titles, thanks to its big feature list and what Firelight proudly claims as an ‘actively developed’ toolkit, boasting monthly major releases to enable a quick turnaround
of new features specified by clients.

FMOD’s API provides a DSP audio engine with high-end features such as 2D and 3D morphing, 3D reverb support and a choice of a low-level API or a data-based equivalent, with performance tuned for each platform.

The second half of the FMOD experience is the FMOD Designer, which gives the power of the system to the sound designer, granting them the ability to completely design the in-game audio seperately and simply provide programmers with assets and an event list, turning sound implementation into a much more efficient data-driven system.

The latest version of the FMOD runtime adds PS3 support for DTS output, oscillators and spectrum analysis, alongside optimizations for reverb on PS3 and Xbox 360 and added API functionality, while the new 1.13 version of the FMOD Designer adds interactive music functionality, integration of the standalone low-level FMOD profiler and a new message log panel.

FMOD is available for all contemporary and last-gen consoles, with a range of licences available scaling from free for non-commercial games to reduced rates for Xbox Live Arcade, PSN or WiiWare titles.
www.fmod.org

WWise

Audiokinetic’s cross-platform audio system Wwise – currently available on PlayStation 3, Xbox 360, PC and Wii – has been designed for use by sound designers and audio programmers, decoupling the two professions and allowing them to work separately while also facilitating the process of linking them up where necessary.

The unified authoring application gives full control to the sound designer, allowing them to author and organise sounds visually and control blends between interactive music segments. The latest version also boasts the new Dynamic Dialogue system, a lightweight and efficient schema of user-defined rules for building and managing dynamic speech. This allows the user to utilise sample-accurate dialogue stitching to build a huge range of speech, including play-by-play commentary.

New to the Wwise product family is Wwise Motion, which gives the audio designer power over PC vibration peripherals and Wii, PS3 and Xbox 360 controllers. The product is designed to free programmers from having to worry about rumble, traditionally left to the last minute, thereby allowing them work on more pressing issues.

Requiring only a single extra line of code and virtually no CPU overhead, Motion can generate vibration patterns automatically from sound data or, if more control is desired, be authored graphically within the Wwise application.

Like some of the other audio engines featured here, Wwise licences come in a variety of flavours, including a reduced flat-fee for digital download titles or a royalty rate of only $0.10 per copy sold.
www.audiokinetic.com

irrKlang

Although its monicker might suggest an extension to the popular Irrlicht open source 3D engine, Austrian team Ambiera’s irrKlang merely takes structural inspiration from the popular game tech, priding itself on being a fully-independent and feature-packed audio engine for Windows, Mac and Linux systems.

Free for non-commerical use, with very reasonable commercial licences available complete with support and source code, irrKlang supports a wide range of audio formats – from the ubiquitous WAV, MP3 and OGG to more specialist formats such as XM, MOD and IT – and is available as both a C++ SDK and a managed API for .NET languages.

The engine features buffered audio playback with automatic resource management and stream/cache determination, dynamic sound effects in 3D such as the Doppler effect in addition to real-time 2D effects such as reverb, echo and distortion. The engine can run on a single thread or in a separate one in multi-processor environments, and has an extensible plug-in architecture for custom functionality.
Optimised for low-end systems, the 3D engine works well even on hardware that couldn’t normally use 3D sound buffers without a significant performance hit, supports multiple rolloff models and integrates into Ambiera’s irrlicht-focused world editing tool irrEdit for precise three-dimensional sound placement.

The engine is updated roughly once per month, and licensing for irrKlang Pro starts at €65 for a product that sells for less than €14 and scales up to €390 for a single product of any price.
www.ambiera.com/irrklang/