This version (21 Jun 2012 14:41) was approved by William Jahn.

SuperPhat Spatializer

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The SuperPhat block is an advanced algorithm that allows for a wider stereo image to be played back from two closely spaced speakers. This spatializer algorithm is only meant to widen signals that are already in stereo format, in order to enhance the image. The function is similar to the Phat-Stereo algorithm but performs a much more advanced implementation of the algorithm to get a better effect.

Input Pins

NameFormat [int/dec] - [control/audio]Function Description
Pin 0: Left Inputdecimal - audioLeft signal Audio input
Pin 1: Right Inputdecimal - audioRight signal Audio input

Output Pins

NameFormat [int/dec] - [control/audio]Function Description
Pin 0: Left Outputdecimal - audioStereo-Enhanced Left signal output
Pin 0: Right Outputdecimal - audioStereo-Enhanced Right signal output

GUI Pins

GUI Control NameDefault ValueRangeFunction Description
Spread Frequency500 Hz250 - 1000Controls the primary frequency used for spatialization.
Effect Gain1.30.5-3Linear Gain value that controls the gain stages used in the effect for stereo spacialization.

DSP Parameter Information

GUI Control NameCompiler NameFunction Description
Spread FrequencySuperPhatAlg1spread1The spread frequency written to the DSP
Effect GainSuperPhatAlg1gainHi
When the Effect Gain is changed, 3 DSP coefficients are written to the Parameter RAM.

Algorithm Description

The SuperPhat algorithm is a playback spatializer that takes a stereo image, and widens the signal for playback from two closely spaced speakers. The algorithm accepts a stereo signal and outputs an enhanced stereo image for playback. The algorithm is based on proprietary filtering and gain adjustment in order to produce the widened image.

The two parameters available for adjustment Spread Frequency and Effect Gain, change the responsiveness of the effect. Depending on the actual physical end system, different values should be used to obtain the optimal effect. Subjective listening tests are the recommended way to set the values for these parameters.


The following schematic image shows the SuperPhat algorithm in comparison with the Phat-Stereo algorithm. Both algorithms have similar functions, but the effect is more pronounced with the SuperPhat algorithm at the cost of more instructions. This image shows the Inputs, stereo mux, and outputs, along with the two methods for stereo spatialization offered in the SigmaStudio library.

Algorithm Details

Toolbox PathADI Algorithms - Surround & 3D Audio - SuperPhat Spatializer
Cores SupportedAD1940
“Grow Algorithm” Supportedno
“Add Algorithm” Supportedno
Subroutine/Loop Basedno
Program RAM162
Data RAM90
Parameter RAM52
resources/tools-software/sigmastudio/toolbox/adialgorithms/superphat.txt · Last modified: 21 Jun 2012 14:41 by William Jahn