diff --git a/webrtc/common.h b/webrtc/common.h
index 58aba517e9..f2a868241d 100644
--- a/webrtc/common.h
+++ b/webrtc/common.h
@@ -32,7 +32,8 @@ enum class ConfigOptionID {
   kExperimentalNs,
   kBeamforming,
   kIntelligibility,
-  kEchoCanceller3
+  kEchoCanceller3,
+  kAecRefinedAdaptiveFilter
 };
 
 // Class Config is designed to ease passing a set of options across webrtc code.
diff --git a/webrtc/modules/audio_processing/aec/aec_core.cc b/webrtc/modules/audio_processing/aec/aec_core.cc
index 4b5abedd5a..f13cf94c2b 100644
--- a/webrtc/modules/audio_processing/aec/aec_core.cc
+++ b/webrtc/modules/audio_processing/aec/aec_core.cc
@@ -25,6 +25,7 @@
 #include <stdlib.h>
 #include <string.h>
 
+#include "webrtc/base/checks.h"
 extern "C" {
 #include "webrtc/common_audio/ring_buffer.h"
 }
@@ -238,15 +239,10 @@ static void FilterFar(int num_partitions,
   }
 }
 
-static void ScaleErrorSignal(int extended_filter_enabled,
-                             float normal_mu,
-                             float normal_error_threshold,
+static void ScaleErrorSignal(float mu,
+                             float error_threshold,
                              float x_pow[PART_LEN1],
                              float ef[2][PART_LEN1]) {
-  const float mu = extended_filter_enabled ? kExtendedMu : normal_mu;
-  const float error_threshold = extended_filter_enabled
-                                    ? kExtendedErrorThreshold
-                                    : normal_error_threshold;
   int i;
   float abs_ef;
   for (i = 0; i < (PART_LEN1); i++) {
@@ -936,11 +932,38 @@ static int SignalBasedDelayCorrection(AecCore* self) {
   return delay_correction;
 }
 
+static void RegressorPower(int num_partitions,
+                           int latest_added_partition,
+                           float x_fft_buf[2]
+                                          [kExtendedNumPartitions * PART_LEN1],
+                           float x_pow[PART_LEN1]) {
+  RTC_DCHECK_LT(latest_added_partition, num_partitions);
+  memset(x_pow, 0, PART_LEN1 * sizeof(x_pow[0]));
+
+  int partition = latest_added_partition;
+  int x_fft_buf_position = partition * PART_LEN1;
+  for (int i = 0; i < num_partitions; ++i) {
+    for (int bin = 0; bin < PART_LEN1; ++bin) {
+      float re = x_fft_buf[0][x_fft_buf_position];
+      float im = x_fft_buf[1][x_fft_buf_position];
+      x_pow[bin] += re * re + im * im;
+      ++x_fft_buf_position;
+    }
+
+    ++partition;
+    if (partition == num_partitions) {
+      partition = 0;
+      RTC_DCHECK_EQ(num_partitions * PART_LEN1, x_fft_buf_position);
+      x_fft_buf_position = 0;
+    }
+  }
+}
+
 static void EchoSubtraction(AecCore* aec,
                             int num_partitions,
                             int extended_filter_enabled,
-                            float normal_mu,
-                            float normal_error_threshold,
+                            float filter_step_size,
+                            float error_threshold,
                             float* x_fft,
                             int* x_fft_buf_block_pos,
                             float x_fft_buf[2]
@@ -1001,8 +1024,7 @@ static void EchoSubtraction(AecCore* aec,
                           sizeof(e_fft[0][0]) * PART_LEN1 * 2);
 
   // Scale error signal inversely with far power.
-  WebRtcAec_ScaleErrorSignal(extended_filter_enabled, normal_mu,
-                             normal_error_threshold, x_pow, e_fft);
+  WebRtcAec_ScaleErrorSignal(filter_step_size, error_threshold, x_pow, e_fft);
   WebRtcAec_FilterAdaptation(num_partitions, *x_fft_buf_block_pos, x_fft_buf,
                              e_fft, h_fft_buf);
   memcpy(echo_subtractor_output, e, sizeof(float) * PART_LEN);
@@ -1315,18 +1337,31 @@ static void ProcessBlock(AecCore* aec) {
   memcpy(fft, aec->dBuf, sizeof(float) * PART_LEN2);
   Fft(fft, df);
 
-  // Power smoothing
-  for (i = 0; i < PART_LEN1; i++) {
-    far_spectrum = (x_fft_ptr[i] * x_fft_ptr[i]) +
-                   (x_fft_ptr[PART_LEN1 + i] * x_fft_ptr[PART_LEN1 + i]);
-    aec->xPow[i] =
-        gPow[0] * aec->xPow[i] + gPow[1] * aec->num_partitions * far_spectrum;
-    // Calculate absolute spectra
-    abs_far_spectrum[i] = sqrtf(far_spectrum);
+  // Power smoothing.
+  if (aec->refined_adaptive_filter_enabled) {
+    for (i = 0; i < PART_LEN1; ++i) {
+      far_spectrum = (x_fft_ptr[i] * x_fft_ptr[i]) +
+                     (x_fft_ptr[PART_LEN1 + i] * x_fft_ptr[PART_LEN1 + i]);
+      // Calculate the magnitude spectrum.
+      abs_far_spectrum[i] = sqrtf(far_spectrum);
+    }
+    RegressorPower(aec->num_partitions, aec->xfBufBlockPos, aec->xfBuf,
+                   aec->xPow);
+  } else {
+    for (i = 0; i < PART_LEN1; ++i) {
+      far_spectrum = (x_fft_ptr[i] * x_fft_ptr[i]) +
+                     (x_fft_ptr[PART_LEN1 + i] * x_fft_ptr[PART_LEN1 + i]);
+      aec->xPow[i] =
+          gPow[0] * aec->xPow[i] + gPow[1] * aec->num_partitions * far_spectrum;
+      // Calculate the magnitude spectrum.
+      abs_far_spectrum[i] = sqrtf(far_spectrum);
+    }
+  }
 
+  for (i = 0; i < PART_LEN1; ++i) {
     near_spectrum = df[0][i] * df[0][i] + df[1][i] * df[1][i];
     aec->dPow[i] = gPow[0] * aec->dPow[i] + gPow[1] * near_spectrum;
-    // Calculate absolute spectra
+    // Calculate the magnitude spectrum.
     abs_near_spectrum[i] = sqrtf(near_spectrum);
   }
 
@@ -1379,7 +1414,7 @@ static void ProcessBlock(AecCore* aec) {
 
   // Perform echo subtraction.
   EchoSubtraction(aec, aec->num_partitions, aec->extended_filter_enabled,
-                  aec->normal_mu, aec->normal_error_threshold, &x_fft[0][0],
+                  aec->filter_step_size, aec->error_threshold, &x_fft[0][0],
                   &aec->xfBufBlockPos, aec->xfBuf, nearend_ptr, aec->xPow,
                   aec->wfBuf, echo_subtractor_output);
 
@@ -1485,6 +1520,7 @@ AecCore* WebRtcAec_CreateAec() {
 #endif
   aec->extended_filter_enabled = 0;
   aec->aec3_enabled = 0;
+  aec->refined_adaptive_filter_enabled = false;
 
   // Assembly optimization
   WebRtcAec_FilterFar = FilterFar;
@@ -1548,18 +1584,53 @@ void WebRtcAec_FreeAec(AecCore* aec) {
   delete aec;
 }
 
+static void SetAdaptiveFilterStepSize(AecCore* aec) {
+  // Extended filter adaptation parameter.
+  // TODO(ajm): No narrowband tuning yet.
+  const float kExtendedMu = 0.4f;
+
+  if (aec->refined_adaptive_filter_enabled) {
+    aec->filter_step_size = 0.05f;
+  } else {
+    if (aec->extended_filter_enabled) {
+      aec->filter_step_size = kExtendedMu;
+    } else {
+      if (aec->sampFreq == 8000) {
+        aec->filter_step_size = 0.6f;
+      } else {
+        aec->filter_step_size = 0.5f;
+      }
+    }
+  }
+}
+
+static void SetErrorThreshold(AecCore* aec) {
+  // Extended filter adaptation parameter.
+  // TODO(ajm): No narrowband tuning yet.
+  static const float kExtendedErrorThreshold = 1.0e-6f;
+
+  if (aec->extended_filter_enabled) {
+    aec->error_threshold = kExtendedErrorThreshold;
+  } else {
+    if (aec->sampFreq == 8000) {
+      aec->error_threshold = 2e-6f;
+    } else {
+      aec->error_threshold = 1.5e-6f;
+    }
+  }
+}
+
 int WebRtcAec_InitAec(AecCore* aec, int sampFreq) {
   int i;
 
   aec->sampFreq = sampFreq;
 
+  SetAdaptiveFilterStepSize(aec);
+  SetErrorThreshold(aec);
+
   if (sampFreq == 8000) {
-    aec->normal_mu = 0.6f;
-    aec->normal_error_threshold = 2e-6f;
     aec->num_bands = 1;
   } else {
-    aec->normal_mu = 0.5f;
-    aec->normal_error_threshold = 1.5e-6f;
     aec->num_bands = (size_t)(sampFreq / 16000);
   }
 
@@ -1930,9 +2001,20 @@ int WebRtcAec_aec3_enabled(AecCore* self) {
   return self->aec3_enabled;
 }
 
+void WebRtcAec_enable_refined_adaptive_filter(AecCore* self, bool enable) {
+  self->refined_adaptive_filter_enabled = enable;
+  SetAdaptiveFilterStepSize(self);
+  SetErrorThreshold(self);
+}
+
+bool WebRtcAec_refined_adaptive_filter_enabled(const AecCore* self) {
+  return self->refined_adaptive_filter_enabled;
+}
 
 void WebRtcAec_enable_extended_filter(AecCore* self, int enable) {
   self->extended_filter_enabled = enable;
+  SetAdaptiveFilterStepSize(self);
+  SetErrorThreshold(self);
   self->num_partitions = enable ? kExtendedNumPartitions : kNormalNumPartitions;
   // Update the delay estimator with filter length.  See InitAEC() for details.
   WebRtc_set_allowed_offset(self->delay_estimator, self->num_partitions / 2);
diff --git a/webrtc/modules/audio_processing/aec/aec_core.h b/webrtc/modules/audio_processing/aec/aec_core.h
index 71f02d6a3e..bd5b283eca 100644
--- a/webrtc/modules/audio_processing/aec/aec_core.h
+++ b/webrtc/modules/audio_processing/aec/aec_core.h
@@ -120,6 +120,12 @@ void WebRtcAec_enable_aec3(AecCore* self, int enable);
 // Returns 1 if the next generation aec is enabled and zero if disabled.
 int WebRtcAec_aec3_enabled(AecCore* self);
 
+// Turns on/off the refined adaptive filter feature.
+void WebRtcAec_enable_refined_adaptive_filter(AecCore* self, bool enable);
+
+// Returns whether the refined adaptive filter is enabled.
+bool WebRtcAec_refined_adaptive_filter(const AecCore* self);
+
 // Enables or disables extended filter mode. Non-zero enables, zero disables.
 void WebRtcAec_enable_extended_filter(AecCore* self, int enable);
 
diff --git a/webrtc/modules/audio_processing/aec/aec_core_internal.h b/webrtc/modules/audio_processing/aec/aec_core_internal.h
index 05f5083c4a..1f7b6b541f 100644
--- a/webrtc/modules/audio_processing/aec/aec_core_internal.h
+++ b/webrtc/modules/audio_processing/aec/aec_core_internal.h
@@ -35,11 +35,6 @@ enum {
   kHistorySizeBlocks = 125
 };
 
-// Extended filter adaptation parameters.
-// TODO(ajm): No narrowband tuning yet.
-static const float kExtendedMu = 0.4f;
-static const float kExtendedErrorThreshold = 1.0e-6f;
-
 typedef struct PowerLevel {
   PowerLevel();
 
@@ -126,12 +121,12 @@ struct AecCore {
   int system_delay;  // Current system delay buffered in AEC.
 
   int mult;  // sampling frequency multiple
-  int sampFreq;
+  int sampFreq = 16000;
   size_t num_bands;
   uint32_t seed;
 
-  float normal_mu;               // stepsize
-  float normal_error_threshold;  // error threshold
+  float filter_step_size;  // stepsize
+  float error_threshold;   // error threshold
 
   int noiseEstCtr;
 
@@ -178,6 +173,7 @@ struct AecCore {
   int extended_filter_enabled;
   // 1 = next generation aec mode enabled, 0 = disabled.
   int aec3_enabled;
+  bool refined_adaptive_filter_enabled;
 
   // Runtime selection of number of filter partitions.
   int num_partitions;
@@ -210,9 +206,8 @@ typedef void (*WebRtcAecFilterFar)(
     float h_fft_buf[2][kExtendedNumPartitions * PART_LEN1],
     float y_fft[2][PART_LEN1]);
 extern WebRtcAecFilterFar WebRtcAec_FilterFar;
-typedef void (*WebRtcAecScaleErrorSignal)(int extended_filter_enabled,
-                                          float normal_mu,
-                                          float normal_error_threshold,
+typedef void (*WebRtcAecScaleErrorSignal)(float mu,
+                                          float error_threshold,
                                           float x_pow[PART_LEN1],
                                           float ef[2][PART_LEN1]);
 extern WebRtcAecScaleErrorSignal WebRtcAec_ScaleErrorSignal;
diff --git a/webrtc/modules/audio_processing/aec/aec_core_mips.cc b/webrtc/modules/audio_processing/aec/aec_core_mips.cc
index 4699e35baf..e12f2ef28a 100644
--- a/webrtc/modules/audio_processing/aec/aec_core_mips.cc
+++ b/webrtc/modules/audio_processing/aec/aec_core_mips.cc
@@ -707,15 +707,10 @@ void WebRtcAec_OverdriveAndSuppress_mips(AecCore* aec,
   }
 }
 
-void WebRtcAec_ScaleErrorSignal_mips(int extended_filter_enabled,
-                                     float normal_mu,
-                                     float normal_error_threshold,
+void WebRtcAec_ScaleErrorSignal_mips(float mu,
+                                     float error_threshold,
                                      float x_pow[PART_LEN1],
                                      float ef[2][PART_LEN1]) {
-  const float mu = extended_filter_enabled ? kExtendedMu : normal_mu;
-  const float error_threshold = extended_filter_enabled
-                                    ? kExtendedErrorThreshold
-                                    : normal_error_threshold;
   int len = (PART_LEN1);
   float* ef0 = ef[0];
   float* ef1 = ef[1];
diff --git a/webrtc/modules/audio_processing/aec/aec_core_neon.cc b/webrtc/modules/audio_processing/aec/aec_core_neon.cc
index 69e8d52c91..12b9359a91 100644
--- a/webrtc/modules/audio_processing/aec/aec_core_neon.cc
+++ b/webrtc/modules/audio_processing/aec/aec_core_neon.cc
@@ -127,15 +127,10 @@ static float32x4_t vsqrtq_f32(float32x4_t s) {
 }
 #endif  // WEBRTC_ARCH_ARM64
 
-static void ScaleErrorSignalNEON(int extended_filter_enabled,
-                                 float normal_mu,
-                                 float normal_error_threshold,
+static void ScaleErrorSignalNEON(float mu,
+                                 float error_threshold,
                                  float x_pow[PART_LEN1],
                                  float ef[2][PART_LEN1]) {
-  const float mu = extended_filter_enabled ? kExtendedMu : normal_mu;
-  const float error_threshold = extended_filter_enabled
-                                    ? kExtendedErrorThreshold
-                                    : normal_error_threshold;
   const float32x4_t k1e_10f = vdupq_n_f32(1e-10f);
   const float32x4_t kMu = vmovq_n_f32(mu);
   const float32x4_t kThresh = vmovq_n_f32(error_threshold);
diff --git a/webrtc/modules/audio_processing/aec/aec_core_sse2.cc b/webrtc/modules/audio_processing/aec/aec_core_sse2.cc
index 254dbf10e3..8fa0166ea1 100644
--- a/webrtc/modules/audio_processing/aec/aec_core_sse2.cc
+++ b/webrtc/modules/audio_processing/aec/aec_core_sse2.cc
@@ -79,17 +79,13 @@ static void FilterFarSSE2(int num_partitions,
   }
 }
 
-static void ScaleErrorSignalSSE2(int extended_filter_enabled,
-                                 float normal_mu,
-                                 float normal_error_threshold,
+static void ScaleErrorSignalSSE2(float mu,
+                                 float error_threshold,
                                  float x_pow[PART_LEN1],
                                  float ef[2][PART_LEN1]) {
   const __m128 k1e_10f = _mm_set1_ps(1e-10f);
-  const __m128 kMu = extended_filter_enabled ? _mm_set1_ps(kExtendedMu)
-                                             : _mm_set1_ps(normal_mu);
-  const __m128 kThresh = extended_filter_enabled
-                             ? _mm_set1_ps(kExtendedErrorThreshold)
-                             : _mm_set1_ps(normal_error_threshold);
+  const __m128 kMu = _mm_set1_ps(mu);
+  const __m128 kThresh = _mm_set1_ps(error_threshold);
 
   int i;
   // vectorized code (four at once)
@@ -124,10 +120,6 @@ static void ScaleErrorSignalSSE2(int extended_filter_enabled,
   }
   // scalar code for the remaining items.
   {
-    const float mu = extended_filter_enabled ? kExtendedMu : normal_mu;
-    const float error_threshold = extended_filter_enabled
-                                      ? kExtendedErrorThreshold
-                                      : normal_error_threshold;
     for (; i < (PART_LEN1); i++) {
       float abs_ef;
       ef[0][i] /= (x_pow[i] + 1e-10f);
diff --git a/webrtc/modules/audio_processing/echo_cancellation_impl.cc b/webrtc/modules/audio_processing/echo_cancellation_impl.cc
index 12ea75efe1..c18ed94bd2 100644
--- a/webrtc/modules/audio_processing/echo_cancellation_impl.cc
+++ b/webrtc/modules/audio_processing/echo_cancellation_impl.cc
@@ -415,7 +415,16 @@ bool EchoCancellationImpl::is_aec3_enabled() const {
 
 std::string EchoCancellationImpl::GetExperimentsDescription() {
   rtc::CritScope cs(crit_capture_);
-  return aec3_enabled_ ? "AEC3" : "";
+  std::string description = (aec3_enabled_ ? "AEC3" : "");
+  if (refined_adaptive_filter_enabled_) {
+    description += ";RefinedAdaptiveFilter";
+  }
+  return description;
+}
+
+bool EchoCancellationImpl::is_refined_adaptive_filter_enabled() const {
+  rtc::CritScope cs(crit_capture_);
+  return refined_adaptive_filter_enabled_;
 }
 
 bool EchoCancellationImpl::is_extended_filter_enabled() const {
@@ -534,6 +543,8 @@ void EchoCancellationImpl::SetExtraOptions(const Config& config) {
     rtc::CritScope cs(crit_capture_);
     extended_filter_enabled_ = config.Get<ExtendedFilter>().enabled;
     delay_agnostic_enabled_ = config.Get<DelayAgnostic>().enabled;
+    refined_adaptive_filter_enabled_ =
+        config.Get<RefinedAdaptiveFilter>().enabled;
     aec3_enabled_ = config.Get<EchoCanceller3>().enabled;
   }
   Configure();
@@ -556,6 +567,9 @@ int EchoCancellationImpl::Configure() {
                                     delay_agnostic_enabled_ ? 1 : 0);
     WebRtcAec_enable_aec3(WebRtcAec_aec_core(canceller->state()),
                           aec3_enabled_ ? 1 : 0);
+    WebRtcAec_enable_refined_adaptive_filter(
+        WebRtcAec_aec_core(canceller->state()),
+        refined_adaptive_filter_enabled_);
     const int handle_error = WebRtcAec_set_config(canceller->state(), config);
     if (handle_error != AudioProcessing::kNoError) {
       error = AudioProcessing::kNoError;
diff --git a/webrtc/modules/audio_processing/echo_cancellation_impl.h b/webrtc/modules/audio_processing/echo_cancellation_impl.h
index b58ba596ea..f67ef7b7da 100644
--- a/webrtc/modules/audio_processing/echo_cancellation_impl.h
+++ b/webrtc/modules/audio_processing/echo_cancellation_impl.h
@@ -48,6 +48,7 @@ class EchoCancellationImpl : public EchoCancellation {
   bool is_extended_filter_enabled() const;
   bool is_aec3_enabled() const;
   std::string GetExperimentsDescription();
+  bool is_refined_adaptive_filter_enabled() const;
 
   // Checks whether the module is enabled. Must only be
   // called from the render side of APM as otherwise
@@ -102,6 +103,7 @@ class EchoCancellationImpl : public EchoCancellation {
   bool extended_filter_enabled_ GUARDED_BY(crit_capture_);
   bool delay_agnostic_enabled_ GUARDED_BY(crit_capture_);
   bool aec3_enabled_ GUARDED_BY(crit_capture_);
+  bool refined_adaptive_filter_enabled_ GUARDED_BY(crit_capture_) = false;
 
   size_t render_queue_element_max_size_ GUARDED_BY(crit_render_)
       GUARDED_BY(crit_capture_);
diff --git a/webrtc/modules/audio_processing/include/audio_processing.h b/webrtc/modules/audio_processing/include/audio_processing.h
index ad95fadb1a..0c93a984b2 100644
--- a/webrtc/modules/audio_processing/include/audio_processing.h
+++ b/webrtc/modules/audio_processing/include/audio_processing.h
@@ -80,6 +80,18 @@ struct EchoCanceller3 {
   bool enabled;
 };
 
+// Enables the refined linear filter adaptation in the echo canceller.
+// This configuration only applies to EchoCancellation and not
+// EchoControlMobile. It can be set in the constructor
+// or using AudioProcessing::SetExtraOptions().
+struct RefinedAdaptiveFilter {
+  RefinedAdaptiveFilter() : enabled(false) {}
+  explicit RefinedAdaptiveFilter(bool enabled) : enabled(enabled) {}
+  static const ConfigOptionID identifier =
+      ConfigOptionID::kAecRefinedAdaptiveFilter;
+  bool enabled;
+};
+
 // Enables delay-agnostic echo cancellation. This feature relies on internally
 // estimated delays between the process and reverse streams, thus not relying
 // on reported system delays. This configuration only applies to
diff --git a/webrtc/modules/audio_processing/test/debug_dump_test.cc b/webrtc/modules/audio_processing/test/debug_dump_test.cc
index 60c1eb9511..3acb69444d 100644
--- a/webrtc/modules/audio_processing/test/debug_dump_test.cc
+++ b/webrtc/modules/audio_processing/test/debug_dump_test.cc
@@ -341,6 +341,83 @@ TEST_F(DebugDumpTest, ToggleDelayAgnosticAec) {
   VerifyDebugDump(generator.dump_file_name());
 }
 
+TEST_F(DebugDumpTest, VerifyRefinedAdaptiveFilterExperimentalString) {
+  Config config;
+  config.Set<RefinedAdaptiveFilter>(new RefinedAdaptiveFilter(true));
+  DebugDumpGenerator generator(config);
+  generator.StartRecording();
+  generator.Process(100);
+  generator.StopRecording();
+
+  DebugDumpReplayer debug_dump_replayer_;
+
+  ASSERT_TRUE(debug_dump_replayer_.SetDumpFile(generator.dump_file_name()));
+
+  while (const rtc::Optional<audioproc::Event> event =
+             debug_dump_replayer_.GetNextEvent()) {
+    debug_dump_replayer_.RunNextEvent();
+    if (event->type() == audioproc::Event::CONFIG) {
+      const audioproc::Config* msg = &event->config();
+      ASSERT_TRUE(msg->has_experiments_description());
+      EXPECT_PRED_FORMAT2(testing::IsSubstring, "RefinedAdaptiveFilter",
+                          msg->experiments_description().c_str());
+    }
+  }
+}
+
+TEST_F(DebugDumpTest, VerifyCombinedExperimentalStringInclusive) {
+  Config config;
+  config.Set<RefinedAdaptiveFilter>(new RefinedAdaptiveFilter(true));
+  config.Set<EchoCanceller3>(new EchoCanceller3(true));
+  DebugDumpGenerator generator(config);
+  generator.StartRecording();
+  generator.Process(100);
+  generator.StopRecording();
+
+  DebugDumpReplayer debug_dump_replayer_;
+
+  ASSERT_TRUE(debug_dump_replayer_.SetDumpFile(generator.dump_file_name()));
+
+  while (const rtc::Optional<audioproc::Event> event =
+             debug_dump_replayer_.GetNextEvent()) {
+    debug_dump_replayer_.RunNextEvent();
+    if (event->type() == audioproc::Event::CONFIG) {
+      const audioproc::Config* msg = &event->config();
+      ASSERT_TRUE(msg->has_experiments_description());
+      EXPECT_PRED_FORMAT2(testing::IsSubstring, "RefinedAdaptiveFilter",
+                          msg->experiments_description().c_str());
+      EXPECT_PRED_FORMAT2(testing::IsSubstring, "AEC3",
+                          msg->experiments_description().c_str());
+    }
+  }
+}
+
+TEST_F(DebugDumpTest, VerifyCombinedExperimentalStringExclusive) {
+  Config config;
+  config.Set<RefinedAdaptiveFilter>(new RefinedAdaptiveFilter(true));
+  DebugDumpGenerator generator(config);
+  generator.StartRecording();
+  generator.Process(100);
+  generator.StopRecording();
+
+  DebugDumpReplayer debug_dump_replayer_;
+
+  ASSERT_TRUE(debug_dump_replayer_.SetDumpFile(generator.dump_file_name()));
+
+  while (const rtc::Optional<audioproc::Event> event =
+             debug_dump_replayer_.GetNextEvent()) {
+    debug_dump_replayer_.RunNextEvent();
+    if (event->type() == audioproc::Event::CONFIG) {
+      const audioproc::Config* msg = &event->config();
+      ASSERT_TRUE(msg->has_experiments_description());
+      EXPECT_PRED_FORMAT2(testing::IsSubstring, "RefinedAdaptiveFilter",
+                          msg->experiments_description().c_str());
+      EXPECT_PRED_FORMAT2(testing::IsNotSubstring, "AEC3",
+                          msg->experiments_description().c_str());
+    }
+  }
+}
+
 TEST_F(DebugDumpTest, VerifyAec3ExperimentalString) {
   Config config;
   config.Set<EchoCanceller3>(new EchoCanceller3(true));
@@ -358,8 +435,9 @@ TEST_F(DebugDumpTest, VerifyAec3ExperimentalString) {
     debug_dump_replayer_.RunNextEvent();
     if (event->type() == audioproc::Event::CONFIG) {
       const audioproc::Config* msg = &event->config();
-      EXPECT_TRUE(msg->has_experiments_description());
-      EXPECT_NE(std::string::npos, msg->experiments_description().find("AEC3"));
+      ASSERT_TRUE(msg->has_experiments_description());
+      EXPECT_PRED_FORMAT2(testing::IsSubstring, "AEC3",
+                          msg->experiments_description().c_str());
     }
   }
 }
@@ -380,7 +458,7 @@ TEST_F(DebugDumpTest, VerifyEmptyExperimentalString) {
     debug_dump_replayer_.RunNextEvent();
     if (event->type() == audioproc::Event::CONFIG) {
       const audioproc::Config* msg = &event->config();
-      EXPECT_TRUE(msg->has_experiments_description());
+      ASSERT_TRUE(msg->has_experiments_description());
       EXPECT_EQ(0u, msg->experiments_description().size());
     }
   }
diff --git a/webrtc/modules/audio_processing/test/process_test.cc b/webrtc/modules/audio_processing/test/process_test.cc
index 0d3921ba18..185bc142d5 100644
--- a/webrtc/modules/audio_processing/test/process_test.cc
+++ b/webrtc/modules/audio_processing/test/process_test.cc
@@ -82,6 +82,7 @@ void usage() {
   printf("  --extended_filter\n");
   printf("  --no_reported_delay\n");
   printf("  --aec3\n");
+  printf("  --refined_adaptive_filter\n");
   printf("\n  -aecm    Echo control mobile\n");
   printf("  --aecm_echo_path_in_file FILE\n");
   printf("  --aecm_echo_path_out_file FILE\n");
@@ -271,6 +272,9 @@ void void_main(int argc, char* argv[]) {
     } else if (strcmp(argv[i], "--aec3") == 0) {
       config.Set<EchoCanceller3>(new EchoCanceller3(true));
 
+    } else if (strcmp(argv[i], "--refined_adaptive_filter") == 0) {
+      config.Set<RefinedAdaptiveFilter>(new RefinedAdaptiveFilter(true));
+
     } else if (strcmp(argv[i], "-aecm") == 0) {
       ASSERT_EQ(apm->kNoError, apm->echo_control_mobile()->Enable(true));