STV8217T datasheet(33/149 Pages) STMICROELECTRONICS

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STV82x7

Dedicated Digital Signal Processor (DSP)

4.6.5

Bass Management Configuration 4

This configuration implements the Simplified Dolby configuration. The center, left surround and right

surround channels are summed and then filtered by the LPF. The composite bass information is

either summed back into the left and right channels or summed with the LFE channel and sent to

the subwoofer output, see Figure 17.

4.7

SRS WOW and TruSurround XT

The SRS

® TruSurround XT™ is a processing system that can accept from 1 to 6 channels on input

and that will generate a 2-channel output signal.

This processing system includes the latest SRS

® algorithms:

● SRS

® WOW™

● SRS

® TruSurround® (Multi-channel signal virtualizer)

4.7.1

SRS TruSurround

The SRS

® TruSurround® is a processing that can accept from 2 to 5 channels on input and that will

generate a 2-channel output signal.

SRS

® TruSurround® uses Head-Related Transfer Function (HRTF) -based frequency tailoring of

(L/R) difference signals to extend the sound image out past the physical boundaries of the speaker

placements to surround channel information. These rear channel HRTF curves have much greater

peak to valley differences at center frequencies. These were chosen to cause rear channel

difference signals to virtualize farther behind the listener and directed to a different virtual position

as compared to front channel signals. Information that is equal (L+R) in the rear surround channels

Figure 17: Implementation of the Bass Management Configuration 4 (Simplified Configuration)

SubW

LFE

-5dB

-10.5dB

-4.5dB

Subwoofer

ON Switch

STV8217T Datasheet(PDF) 33 Page - STMicroelectronics