SLUUDB4 June   2025 TAS5830

 

  1.   1
  2.   Abstract
  3.   Trademarks
  4. 1General Overview
    1. 1.1 Supported Use Cases
  5. 2Process Flows
    1. 2.1  Overview
    2. 2.2  Process Flow 1
      1. 2.2.1  SRC
      2. 2.2.2  Input Mixer
      3. 2.2.3  Equalizer
      4. 2.2.4  Volume
      5. 2.2.5  DPEQ
      6. 2.2.6  3-Band DRC
      7. 2.2.7  AGL
      8. 2.2.8  Clipper
      9. 2.2.9  Output Crossbar
      10. 2.2.10 DSP Memory Map
    3. 2.3  Process Flow 2
      1. 2.3.1 SRC
      2. 2.3.2 Input Mixer
      3. 2.3.3 Equalizer
      4. 2.3.4 Volume
      5. 2.3.5 2-Band DRC
      6. 2.3.6 AGL
      7. 2.3.7 Clipper
      8. 2.3.8 Output Crossbar
      9. 2.3.9 DSP Memory Map
    4. 2.4  Process Flow 3
      1. 2.4.1 SRC
      2. 2.4.2 Input Mixer
      3. 2.4.3 Equalizer
      4. 2.4.4 Volume
      5. 2.4.5 2-Band DRC
      6. 2.4.6 AGL
      7. 2.4.7 Clipper
      8. 2.4.8 Output Crossbar
      9. 2.4.9 DSP Memory Map
    5. 2.5  Process Flow 4
      1. 2.5.1 SRC
      2. 2.5.2 Volume
      3. 2.5.3 DSP Memory Map
    6. 2.6  Process Flow 5
      1. 2.6.1  SRC
      2. 2.6.2  Input Mixer
      3. 2.6.3  Equalizer
      4. 2.6.4  Volume
      5. 2.6.5  DPEQ
      6. 2.6.6  3-Band DRC
      7. 2.6.7  AGL
      8. 2.6.8  Clipper
      9. 2.6.9  Output Crossbar
      10. 2.6.10 DSP Memory Map
    7. 2.7  Process Flow 6
      1. 2.7.1 SRC
      2. 2.7.2 Input Mixer
      3. 2.7.3 Equalizer
      4. 2.7.4 Volume
      5. 2.7.5 2-Band DRC
      6. 2.7.6 AGL
      7. 2.7.7 Clipper
      8. 2.7.8 Output Crossbar
      9. 2.7.9 DSP Memory Map
    8. 2.8  Process Flow 7
      1. 2.8.1 SRC
      2. 2.8.2 Input Mixer
      3. 2.8.3 Equalizer
      4. 2.8.4 Volume
      5. 2.8.5 2-Band DRC
      6. 2.8.6 AGL
      7. 2.8.7 Clipper
      8. 2.8.8 Output Crossbar
      9. 2.8.9 DSP Memory Map
    9. 2.9  Process Flow 8
      1. 2.9.1 SRC
      2. 2.9.2 Volume
      3. 2.9.3 DSP Memory Map
    10. 2.10 Process Flow 9
      1. 2.10.1 SRC
      2. 2.10.2 Input Mixer
      3. 2.10.3 Equalizer
      4. 2.10.4 Volume
      5. 2.10.5 2-Band DRC
      6. 2.10.6 1-Band DRC
      7. 2.10.7 Output Crossbar
      8. 2.10.8 DSP Memory Map
  6. 3Audio Processing Blocks
    1. 3.1 Input Mixer
    2. 3.2 Equalizer
    3. 3.3 Volume
    4. 3.4 DPEQ
      1. 3.4.1 DPEQ
      2. 3.4.2 Energy Sense
      3. 3.4.3 Low Level EQ
      4. 3.4.4 High Level EQ
    5. 3.5 3-Band DRC
      1. 3.5.1 DRC Time Constant
      2. 3.5.2 Crossover
    6. 3.6 2-Band DRC
      1. 3.6.1 DRC Time Constant
      2. 3.6.2 Crossover
    7. 3.7 AGL
    8. 3.8 Clipper
    9. 3.9 Output Crossbar
  7.   A Appendix
    1.     A.1 DSP Memory Map for Process Flows 1 and 5
    2.     A.2 DSP Memory Map for Process Flow 2, 3, 6 and 7
    3.     A.3 DSP Memory Map for Process Flow 4 and 8
    4.     A.4 DSP Memory Map for Process 9

3.2 Equalizer

The equalizers are implemented using cascaded “direct form 1” BQs structures as shown in Figure 3-4.

Cascaded BQ StructureFigure 3-4 Cascaded BQ Structure

All BQ coefficients are normalized with a0 to insure that B0 is equal to 1. The structure requires 5 BQ coefficients as shown in Table 3-1.

Table 3-1 BQ Coefficients Normalization
BQ COEFFICIENTCOEFFICIENT CALCULATION
B0_DSPb0 / a0
B1_DSPb1 / (a0 × 2)
B2_DSPb2 / a0
A1_DSP–a1 / (a0 × 2)
A2_DSP–a2 / a0

The Equalizer Tuning Window shown below in Figure 3-5 contains 14 independent filters for both left and right channels. They are designed for tuning the frequency response of the overall system. This is where the bulk of the frequency compensation occurs. Complex tuning shapes can be made to compensate for deficiencies in speaker response.

Equalizer Tuning WindowFigure 3-5 Equalizer Tuning Window

As Figure 3-5 shows, each filter has quite a few different filter types and can be turned on or off independently. All the changes to these filters are reflected in the plot above. The composite plot (red) shows the overall frequency response alteration applied to the incoming digital audio data.

The equalizers for left and right channels are ganged by default, but they can be configured independently by deselecting “Gang” option.