3D Spatialization

When creating sample instruments, it can be very helpful to already pre-mix the individual Zones or layers, so that the instrument can be used immediately in a musical context. While adjusting volume and pan already makes for interesting results, sometimes you need more realistic spatial control over placement of sounds in the sound field. These days it’s also increasingly important to be able to spatialize sounds not just in the 2.0/stereo domain, but also in more complex speakers configurations as 4.0 or 5.0. Moreover, Keymap should be able to print these spatial qualities to the samples so that your sampler can play the samples as we mixed and heard them in Keymap. The realtime Surround+Space mixer in Keymap is the answer to these needs.

This mixer has 16 stereo input busses coming from Zones, and the output can be configured for two, four or five speakers. The output configuration and the busses to use for speakers are selected though the Speakers Configuration and the related Front, Read and Front Center pop-up menus.

Distance-related additional effects

Some algorithms let you also enable distance-related spatialization effects:

Distance Filtering progressively dampens the sound as the distance increases to emulate the attenuation of high frequencies as happens in real, open spaces. You enable and disable it through the Fi checkbox in the surround bus table.

Distance Attenuation progressively dampens the sound as the distance increases to emulate the attenuation of high frequencies happening in real, open spaces. Each bus has an independent Distance Attenuation parameter, which sets the volume attenuation at the maximum distance, and can be enabled and disabled through the A checkbox in the surround bus table

Distance Ambience progressively adds ambience to the sound as the distance increases to emulate sound field ambience reflections. This is enabled and disabled through the R checkbox in the surround bus table

Five different algorithms

Samples can be placed in the soundfield with Azimuth , Elevation and Distance parameters and 5 algorithms.

• EqualPower: this algorithm is intended for 2.0 output and implements a simple equal power panner driven by the azimuth parameter. The elevation parameter is ignored by this algorithm.

• HRTF (Head-related transfer function) : this algorithm uses convolution to model of the human head, and filters the audio  to simulate the diffraction and reflection properties of the head, pinna, and torso, before the sound reaches the eardrum and the inner ear. Biologically, the source-location-specific prefiltering effects of these external structures aid in the determination of source location, particularly the determination of source elevation. Thus, the HRTF is used to create the impression of surround sound without multiple speakers. 

• Spherical Head: this algorithm is similar to HRTF, but uses a mathematical model instead of convolution.

• Soundfield: this algorithm takes the audio from the bus and distributes it amongst all the output channels with a weighting toward the location in which the sound derives. It is very effective for ambient sounds, which may derive from a specific location in space, yet should be heard through the listener's entire space.

Vector: this algorithm is similar to Soundfield, but the sound is more focused to the output channels near the location in space of the sound source.