diff --git a/modules/audio_processing/aec3/cascaded_biquad_filter.cc b/modules/audio_processing/aec3/cascaded_biquad_filter.cc
index 9a472f516f..5881d60ae3 100644
--- a/modules/audio_processing/aec3/cascaded_biquad_filter.cc
+++ b/modules/audio_processing/aec3/cascaded_biquad_filter.cc
@@ -13,37 +13,68 @@
 
 namespace webrtc {
 
+CascadedBiQuadFilter::BiQuadParam::BiQuadParam(std::complex<float> zero,
+                                               std::complex<float> pole,
+                                               float gain)
+    : zero(zero), pole(pole), gain(gain) {}
+
+CascadedBiQuadFilter::BiQuad::BiQuad(
+    const CascadedBiQuadFilter::BiQuadParam& param)
+    : x(), y() {
+  float z_r = std::real(param.zero);
+  float z_i = std::imag(param.zero);
+  float p_r = std::real(param.pole);
+  float p_i = std::imag(param.pole);
+  float gain = param.gain;
+
+  coefficients.b[0] = gain * 1.f;
+  coefficients.b[1] = gain * -2.f * z_r;
+  coefficients.b[2] = gain * (z_r * z_r + z_i * z_i);
+
+  coefficients.a[0] = -2.f * p_r;
+  coefficients.a[1] = p_r * p_r + p_i * p_i;
+}
+
 CascadedBiQuadFilter::CascadedBiQuadFilter(
     const CascadedBiQuadFilter::BiQuadCoefficients& coefficients,
     size_t num_biquads)
-    : biquad_states_(num_biquads), coefficients_(coefficients) {}
+    : biquads_(num_biquads, coefficients) {}
+
+CascadedBiQuadFilter::CascadedBiQuadFilter(
+    const std::vector<CascadedBiQuadFilter::BiQuadParam>& biquad_params) {
+  for (const auto& param : biquad_params) {
+    biquads_.push_back(BiQuad(param));
+  }
+}
 
 CascadedBiQuadFilter::~CascadedBiQuadFilter() = default;
 
 void CascadedBiQuadFilter::Process(rtc::ArrayView<const float> x,
                                    rtc::ArrayView<float> y) {
-  ApplyBiQuad(x, y, &biquad_states_[0]);
-  for (size_t k = 1; k < biquad_states_.size(); ++k) {
-    ApplyBiQuad(y, y, &biquad_states_[k]);
+  if (biquads_.size() > 0) {
+    ApplyBiQuad(x, y, &biquads_[0]);
+    for (size_t k = 1; k < biquads_.size(); ++k) {
+      ApplyBiQuad(y, y, &biquads_[k]);
+    }
+  } else {
+    std::copy(x.begin(), x.end(), y.begin());
   }
 }
 
 void CascadedBiQuadFilter::Process(rtc::ArrayView<float> y) {
-  for (auto& biquad : biquad_states_) {
+  for (auto& biquad : biquads_) {
     ApplyBiQuad(y, y, &biquad);
   }
 }
 
-void CascadedBiQuadFilter::ApplyBiQuad(
-    rtc::ArrayView<const float> x,
-    rtc::ArrayView<float> y,
-    CascadedBiQuadFilter::BiQuadState* biquad_state) {
+void CascadedBiQuadFilter::ApplyBiQuad(rtc::ArrayView<const float> x,
+                                       rtc::ArrayView<float> y,
+                                       CascadedBiQuadFilter::BiQuad* biquad) {
   RTC_DCHECK_EQ(x.size(), y.size());
-  RTC_DCHECK(biquad_state);
-  const auto* c_b = coefficients_.b;
-  const auto* c_a = coefficients_.a;
-  auto* m_x = biquad_state->x;
-  auto* m_y = biquad_state->y;
+  const auto* c_b = biquad->coefficients.b;
+  const auto* c_a = biquad->coefficients.a;
+  auto* m_x = biquad->x;
+  auto* m_y = biquad->y;
   for (size_t k = 0; k < x.size(); ++k) {
     const float tmp = x[k];
     y[k] = c_b[0] * tmp + c_b[1] * m_x[0] + c_b[2] * m_x[1] - c_a[0] * m_y[0] -
diff --git a/modules/audio_processing/aec3/cascaded_biquad_filter.h b/modules/audio_processing/aec3/cascaded_biquad_filter.h
index aea889ab53..feae68d63d 100644
--- a/modules/audio_processing/aec3/cascaded_biquad_filter.h
+++ b/modules/audio_processing/aec3/cascaded_biquad_filter.h
@@ -11,6 +11,7 @@
 #ifndef MODULES_AUDIO_PROCESSING_AEC3_CASCADED_BIQUAD_FILTER_H_
 #define MODULES_AUDIO_PROCESSING_AEC3_CASCADED_BIQUAD_FILTER_H_
 
+#include <complex>
 #include <vector>
 
 #include "api/array_view.h"
@@ -18,14 +19,15 @@
 
 namespace webrtc {
 
-// Applies a number of identical biquads in a cascaded manner. The filter
-// implementation is direct form 1.
+// Applies a number of biquads in a cascaded manner. The filter implementation
+// is direct form 1.
 class CascadedBiQuadFilter {
  public:
-  struct BiQuadState {
-    BiQuadState() : x(), y() {}
-    float x[2];
-    float y[2];
+  struct BiQuadParam {
+    BiQuadParam(std::complex<float> zero, std::complex<float> pole, float gain);
+    std::complex<float> zero;
+    std::complex<float> pole;
+    float gain;
   };
 
   struct BiQuadCoefficients {
@@ -33,9 +35,20 @@ class CascadedBiQuadFilter {
     float a[2];
   };
 
+  struct BiQuad {
+    BiQuad(const BiQuadCoefficients& coefficients)
+        : coefficients(coefficients), x(), y() {}
+    BiQuad(const CascadedBiQuadFilter::BiQuadParam& param);
+    BiQuadCoefficients coefficients;
+    float x[2];
+    float y[2];
+  };
+
   CascadedBiQuadFilter(
       const CascadedBiQuadFilter::BiQuadCoefficients& coefficients,
       size_t num_biquads);
+  CascadedBiQuadFilter(
+      const std::vector<CascadedBiQuadFilter::BiQuadParam>& biquad_params);
   ~CascadedBiQuadFilter();
   // Applies the biquads on the values in x in order to form the output in y.
   void Process(rtc::ArrayView<const float> x, rtc::ArrayView<float> y);
@@ -45,10 +58,9 @@ class CascadedBiQuadFilter {
  private:
   void ApplyBiQuad(rtc::ArrayView<const float> x,
                    rtc::ArrayView<float> y,
-                   CascadedBiQuadFilter::BiQuadState* biquad_state);
+                   CascadedBiQuadFilter::BiQuad* biquad);
 
-  std::vector<BiQuadState> biquad_states_;
-  const BiQuadCoefficients coefficients_;
+  std::vector<BiQuad> biquads_;
 
   RTC_DISALLOW_IMPLICIT_CONSTRUCTORS(CascadedBiQuadFilter);
 };
diff --git a/modules/audio_processing/aec3/cascaded_biquad_filter_unittest.cc b/modules/audio_processing/aec3/cascaded_biquad_filter_unittest.cc
index fcb77e1f6e..0f1b0db14b 100644
--- a/modules/audio_processing/aec3/cascaded_biquad_filter_unittest.cc
+++ b/modules/audio_processing/aec3/cascaded_biquad_filter_unittest.cc
@@ -95,4 +95,32 @@ TEST(CascadedBiquadFilter, InputSizeCheckVerification) {
 }
 #endif
 
+// Verifies the conversion from zero, pole, gain to filter coefficients for
+// lowpass filter.
+TEST(CascadedBiquadFilter, BiQuadParamLowPass) {
+  CascadedBiQuadFilter::BiQuadParam param(
+      {-1.0f, 0.0f}, {0.23146901f, 0.39514232f}, 0.1866943331163784f);
+  CascadedBiQuadFilter::BiQuad filter(param);
+  const float epsilon = 1e-6f;
+  EXPECT_NEAR(filter.coefficients.b[0], 0.18669433f, epsilon);
+  EXPECT_NEAR(filter.coefficients.b[1], 0.37338867f, epsilon);
+  EXPECT_NEAR(filter.coefficients.b[2], 0.18669433f, epsilon);
+  EXPECT_NEAR(filter.coefficients.a[0], -0.46293803f, epsilon);
+  EXPECT_NEAR(filter.coefficients.a[1], 0.20971536f, epsilon);
+}
+
+// Verifies the conversion from zero, pole, gain to filter coefficients for
+// highpass filter.
+TEST(CascadedBiquadFilter, BiQuadParamHighPass) {
+  CascadedBiQuadFilter::BiQuadParam param(
+      {1.0f, 0.0f}, {0.72712179f, 0.21296904f}, 0.75707637533388494f);
+  CascadedBiQuadFilter::BiQuad filter(param);
+  const float epsilon = 1e-6f;
+  EXPECT_NEAR(filter.coefficients.b[0], 0.75707638f, epsilon);
+  EXPECT_NEAR(filter.coefficients.b[1], -1.51415275f, epsilon);
+  EXPECT_NEAR(filter.coefficients.b[2], 0.75707638f, epsilon);
+  EXPECT_NEAR(filter.coefficients.a[0], -1.45424359f, epsilon);
+  EXPECT_NEAR(filter.coefficients.a[1], 0.57406192f, epsilon);
+}
+
 }  // namespace webrtc
diff --git a/modules/audio_processing/aec3/decimator.cc b/modules/audio_processing/aec3/decimator.cc
index 6135db5bc2..8fffc8aba9 100644
--- a/modules/audio_processing/aec3/decimator.cc
+++ b/modules/audio_processing/aec3/decimator.cc
@@ -21,8 +21,8 @@ const CascadedBiQuadFilter::BiQuadCoefficients kLowPassFilterCoefficients2 = {
     {-0.27666461f, 0.18513647f}};
 constexpr int kNumFilters2 = 3;
 
-// b, a = signal.butter(2, 1500/8000.0, 'lowpass', analog=False) which are the
-// same as b, a = signal.butter(2, 75/4000.0, 'lowpass', analog=False).
+// b, a = signal.butter(2, 750/8000.0, 'lowpass', analog=False) which are the
+// same as b, a = signal.butter(2, 375/4000.0, 'lowpass', analog=False).
 const CascadedBiQuadFilter::BiQuadCoefficients kLowPassFilterCoefficients4 = {
     {0.0179f, 0.0357f, 0.0179f},
     {-1.5879f, 0.6594f}};