When comparing OpenAL vs FMOD Studio, the Slant community recommends OpenAL for most people. In the question“What are the best audio engines?” OpenAL is ranked 1st while FMOD Studio is ranked 4th. The most important reason people chose OpenAL is:
OpenAL Soft is an LGPL-licensed, cross-platform, software implementation of the OpenAL 3D audio API. It's forked from the open-sourced Windows version available originally from openal.org's SVN repository (now defunct).
Ranked in these QuestionsQuestion Ranking
Pros
Pro Has an open-source alternative
OpenAL Soft is an LGPL-licensed, cross-platform, software implementation of the OpenAL 3D audio API. It's forked from the open-sourced Windows version available originally from openal.org's SVN repository (now defunct).
Pro Cross-platform
Pro Cross-platform
Windows, Windows Phone, Mac OS X, iOS, Android, Linux, PS3, PS4, PSVita, Xbox 360, Xbox One, Wii U
Pro Studio interface presents a lot on one view really well
Compared to Wwise, for example, which splits the parameter curves that may be affecting your event into at least three different views, FMOD does a good job of flattening the hierarchy, simplifying details into nice UI gadgets, and presenting all this on one view. This may create a bit of a disconnect in understanding the hierarchy... but not really. Details may be hidden because of this but those probably aren't missed by your average developer. Showing the waveforms of the clips everywhere possible also helps. The contrast and readability of the UI is also nice.
Pro Unreal game engine integration fully supported
Pro Unity game engine integration fully supported
Well, fully supported except for parameterized one-shot events through FMOD's Unity components, and lack of good getting started documentation showing best practices for various needs.
Pro Autopitch modulator
Easy to automate pitch bending with an RPM parameter, for example. Far easier to use and understand than Wwise's Smart pitch curve command. No idea which is more efficient, however.
Pro Used in many high profile commercial games
Pro Free license for non-commercial/educational/indies (budget < $100k)
Pro Already integrated with many game engines
Cons
Con LGPL is hard to use on mobile
You cannot easily meet the requirements and publish to the iOS App Store or the Google Play Store.
Con Not enough sensitivity in randomized playlists
The smallest chance of random play is 1%. This may be fine enough for most situations but if, for example, you have 20 clips to randomize and you want one of them to play 1:10 of the rest, you would need ~0.5%. And if you want an Easter-egg event at 1:100, you can't get even close to that. You'll have to do it in code instead of in the studio.
Con Unclear on how to handle parameterized one-shot events in Unity
The instructions on how to set up events in Unity work for all events except one-shot events that need to respond to a parameter. These events should be implemented through code instead of using the FMOD Unity components (like you can for all other events). This makes no sense from a design point and is not made clear in any documentation. You might as well implement all of FMOD through code in Unity and ignore the clumsy Unity components.