Sound Blaster X-Fi - X-Fi Features - CMSS-3D

CMSS-3D

"CMSS-3D recreates realistic surround sound from any audio source and puts you right in the center of the action, whether you are using multichannel speakers or headphones." CMSS-3D is a DSP feature that provides audio enhancement. Depending on the equipment used, CMSS-3D has 3 variants:

• CMSS-3D Headphone: When the Creative Control Panel is set to Headphones, this setting creates virtual 3D positional audio via synthesized binaural cues (see Sound localization and Head-related transfer function). If the application generating the audio uses a hardware-accelerated 3D audio API (i.e. DirectSound3D or OpenAL), the input for the binaural synthesis algorithms consists of up to 128 sound sources positioned arbitrarily in 3D space, this is the most accurate utilisation of CMSS-3D. If the application instead generates multi-channel sound directly (e.g. a media player app or a game with software-based audio processing), the input for the binaural synthesis algorithms consist of the 4 to 7 positional sound sources associated with the application's selected speaker configuration. Such applications may use the Speakers settings defined by Windows in which case it is possible to set the Windows Speakers configuration to a multichannel set-up, e.g 5.1, so that the application will output multi channel audio.
• CMSS-3D Virtual (Stereo Xpand): When the Creative Control Panel is set to 2/2.1 or 4/4.1 speakers, this setting creates virtual 3D positional audio similar to CMSS-3DHeadphone. The difference is that this includes techniques such as crosstalk cancellation because sound from all speakers reaches BOTH ears which makes the binaural cues more complicated to synthesize. Additionally, the listener must be located in the "sweet spot" between all of the speakers for the effect to work properly. Note that this is not available (including MacroFX and ElevationFilter) when using 5.1 or more speakers. In these cases, 3D audio sources are mapped to speakers by manipulating the relative volume levels for the different speaker positions. Hardware accelerated 3D-audio is still handled as positional audio but translated using the more complex binaural algorithms. Note that more recent driver versions force the synchronisation between Windows Speakers configuration and the X-Fi control panel when this was previously optional so unlike CMSS-3D Headphone some multi-channel applications will not make use of the technology.
• CMSS-3D Surround: When the Creative Control Panel is set to 4/4.1, 5.1, 6.1, or 7.1 speakers, this setting will upmix stereo sources to multiple channels. Note that both CMSS-3DSurround and CMSS-3DVirtual can be enabled when using 4/4.1 speakers. As above hardware-accelerated 3D audio will be translated to the number of channels specified.