diff --git a/api/test/audioproc_float.cc b/api/test/audioproc_float.cc
index bba9c62..c8d7ff7 100644
--- a/api/test/audioproc_float.cc
+++ b/api/test/audioproc_float.cc
@@ -17,6 +17,12 @@
 namespace webrtc {
 namespace test {
 
+int AudioprocFloat(rtc::scoped_refptr<AudioProcessing> audio_processing,
+                   int argc,
+                   char* argv[]) {
+  return AudioprocFloatImpl(std::move(audio_processing), argc, argv);
+}
+
 int AudioprocFloat(std::unique_ptr<AudioProcessingBuilder> ap_builder,
                    int argc,
                    char* argv[]) {
diff --git a/api/test/audioproc_float.h b/api/test/audioproc_float.h
index 2625e6a..fec2ad1 100644
--- a/api/test/audioproc_float.h
+++ b/api/test/audioproc_float.h
@@ -22,6 +22,22 @@
 // This is an interface for the audio processing simulation utility. This
 // utility can be used to simulate the audioprocessing module using a recording
 // (either an AEC dump or wav files), and generate the output as a wav file.
+// Any audio_processing object specified in the input is used for the
+// simulation. The optional |audio_processing| object provides the
+// AudioProcessing instance that is used during the simulation. Note that when
+// the audio_processing object is specified all functionality that relies on
+// using the AudioProcessingBuilder is deactivated, since the AudioProcessing
+// object is already created and the builder is not used in the simulation. It
+// is needed to pass the command line flags as |argc| and |argv|, so these can
+// be interpreted properly by the utility. To see a list of all supported
+// command line flags, run the executable with the '--help' flag.
+int AudioprocFloat(rtc::scoped_refptr<AudioProcessing> audio_processing,
+                   int argc,
+                   char* argv[]);
+
+// This is an interface for the audio processing simulation utility. This
+// utility can be used to simulate the audioprocessing module using a recording
+// (either an AEC dump or wav files), and generate the output as a wav file.
 // The |ap_builder| object will be used to create the AudioProcessing instance
 // that is used during the simulation. The |ap_builder| supports setting of
 // injectable components, which will be passed on to the created AudioProcessing
diff --git a/modules/audio_processing/test/aec_dump_based_simulator.cc b/modules/audio_processing/test/aec_dump_based_simulator.cc
index b3b113d..f5bd645 100644
--- a/modules/audio_processing/test/aec_dump_based_simulator.cc
+++ b/modules/audio_processing/test/aec_dump_based_simulator.cc
@@ -66,8 +66,11 @@
 
 AecDumpBasedSimulator::AecDumpBasedSimulator(
     const SimulationSettings& settings,
+    rtc::scoped_refptr<AudioProcessing> audio_processing,
     std::unique_ptr<AudioProcessingBuilder> ap_builder)
-    : AudioProcessingSimulator(settings, std::move(ap_builder)) {
+    : AudioProcessingSimulator(settings,
+                               std::move(audio_processing),
+                               std::move(ap_builder)) {
   MaybeOpenCallOrderFile();
 }
 
@@ -206,7 +209,8 @@
 }
 
 void AecDumpBasedSimulator::Process() {
-  CreateAudioProcessor();
+  ConfigureAudioProcessor();
+
   if (settings_.artificial_nearend_filename) {
     std::unique_ptr<WavReader> artificial_nearend_file(
         new WavReader(settings_.artificial_nearend_filename->c_str()));
@@ -237,7 +241,7 @@
     fclose(dump_input_file_);
   }
 
-  DestroyAudioProcessor();
+  DetachAecDump();
 }
 
 void AecDumpBasedSimulator::HandleEvent(
diff --git a/modules/audio_processing/test/aec_dump_based_simulator.h b/modules/audio_processing/test/aec_dump_based_simulator.h
index ef032d0..092b82b 100644
--- a/modules/audio_processing/test/aec_dump_based_simulator.h
+++ b/modules/audio_processing/test/aec_dump_based_simulator.h
@@ -33,6 +33,7 @@
 class AecDumpBasedSimulator final : public AudioProcessingSimulator {
  public:
   AecDumpBasedSimulator(const SimulationSettings& settings,
+                        rtc::scoped_refptr<AudioProcessing> audio_processing,
                         std::unique_ptr<AudioProcessingBuilder> ap_builder);
   ~AecDumpBasedSimulator() override;
 
diff --git a/modules/audio_processing/test/audio_processing_simulator.cc b/modules/audio_processing/test/audio_processing_simulator.cc
index a37a83f..adbc298 100644
--- a/modules/audio_processing/test/audio_processing_simulator.cc
+++ b/modules/audio_processing/test/audio_processing_simulator.cc
@@ -113,10 +113,10 @@
 
 AudioProcessingSimulator::AudioProcessingSimulator(
     const SimulationSettings& settings,
+    rtc::scoped_refptr<AudioProcessing> audio_processing,
     std::unique_ptr<AudioProcessingBuilder> ap_builder)
     : settings_(settings),
-      ap_builder_(ap_builder ? std::move(ap_builder)
-                             : std::make_unique<AudioProcessingBuilder>()),
+      ap_(std::move(audio_processing)),
       analog_mic_level_(settings.initial_mic_level),
       fake_recording_device_(
           settings.initial_mic_level,
@@ -139,6 +139,51 @@
 
   if (settings_.simulate_mic_gain)
     RTC_LOG(LS_VERBOSE) << "Simulating analog mic gain";
+
+  // Create the audio processing object.
+  RTC_CHECK(!(ap_ && ap_builder))
+      << "The AudioProcessing and the AudioProcessingBuilder cannot both be "
+         "specified at the same time.";
+
+  if (ap_) {
+    RTC_CHECK(!settings_.aec_settings_filename);
+    RTC_CHECK(!settings_.print_aec_parameter_values);
+  } else {
+    // Use specied builder if such is provided, otherwise create a new builder.
+    std::unique_ptr<AudioProcessingBuilder> builder =
+        !!ap_builder ? std::move(ap_builder)
+                     : std::make_unique<AudioProcessingBuilder>();
+
+    // Create and set an EchoCanceller3Factory if needed.
+    const bool use_aec = settings_.use_aec && *settings_.use_aec;
+    if (use_aec) {
+      EchoCanceller3Config cfg;
+      if (settings_.aec_settings_filename) {
+        if (settings_.use_verbose_logging) {
+          std::cout << "Reading AEC Parameters from JSON input." << std::endl;
+        }
+        cfg = ReadAec3ConfigFromJsonFile(*settings_.aec_settings_filename);
+      }
+
+      if (settings_.linear_aec_output_filename) {
+        cfg.filter.export_linear_aec_output = true;
+      }
+
+      if (settings_.print_aec_parameter_values) {
+        if (!settings_.use_quiet_output) {
+          std::cout << "AEC settings:" << std::endl;
+        }
+        std::cout << Aec3ConfigToJsonString(cfg) << std::endl;
+      }
+
+      auto echo_control_factory = std::make_unique<EchoCanceller3Factory>(cfg);
+      builder->SetEchoControlFactory(std::move(echo_control_factory));
+    }
+
+    // Create an audio processing object.
+    ap_ = builder->Create();
+    RTC_CHECK(ap_);
+  }
 }
 
 AudioProcessingSimulator::~AudioProcessingSimulator() {
@@ -369,16 +414,14 @@
   ++output_reset_counter_;
 }
 
-void AudioProcessingSimulator::DestroyAudioProcessor() {
+void AudioProcessingSimulator::DetachAecDump() {
   if (settings_.aec_dump_output_filename) {
     ap_->DetachAecDump();
   }
 }
 
-void AudioProcessingSimulator::CreateAudioProcessor() {
-  Config config;
+void AudioProcessingSimulator::ConfigureAudioProcessor() {
   AudioProcessing::Config apm_config;
-  std::unique_ptr<EchoControlFactory> echo_control_factory;
   if (settings_.use_ts) {
     apm_config.transient_suppression.enabled = *settings_.use_ts;
   }
@@ -421,29 +464,6 @@
   apm_config.echo_canceller.export_linear_aec_output =
       !!settings_.linear_aec_output_filename;
 
-  if (use_aec) {
-    EchoCanceller3Config cfg;
-    if (settings_.aec_settings_filename) {
-      if (settings_.use_verbose_logging) {
-        std::cout << "Reading AEC Parameters from JSON input." << std::endl;
-      }
-      cfg = ReadAec3ConfigFromJsonFile(*settings_.aec_settings_filename);
-    }
-
-    if (settings_.linear_aec_output_filename) {
-      cfg.filter.export_linear_aec_output = true;
-    }
-
-    echo_control_factory.reset(new EchoCanceller3Factory(cfg));
-
-    if (settings_.print_aec_parameter_values) {
-      if (!settings_.use_quiet_output) {
-        std::cout << "AEC settings:" << std::endl;
-      }
-      std::cout << Aec3ConfigToJsonString(cfg) << std::endl;
-    }
-  }
-
   if (settings_.use_hpf) {
     apm_config.high_pass_filter.enabled = *settings_.use_hpf;
   }
@@ -512,14 +532,6 @@
         *settings_.ns_analysis_on_linear_aec_output;
   }
 
-  RTC_CHECK(ap_builder_);
-  if (echo_control_factory) {
-    ap_builder_->SetEchoControlFactory(std::move(echo_control_factory));
-  }
-  ap_.reset((*ap_builder_).Create(config));
-
-  RTC_CHECK(ap_);
-
   ap_->ApplyConfig(apm_config);
 
   if (settings_.use_ts) {
diff --git a/modules/audio_processing/test/audio_processing_simulator.h b/modules/audio_processing/test/audio_processing_simulator.h
index fa6efc2..8579f4b 100644
--- a/modules/audio_processing/test/audio_processing_simulator.h
+++ b/modules/audio_processing/test/audio_processing_simulator.h
@@ -150,8 +150,8 @@
 // Provides common functionality for performing audioprocessing simulations.
 class AudioProcessingSimulator {
  public:
-
   AudioProcessingSimulator(const SimulationSettings& settings,
+                           rtc::scoped_refptr<AudioProcessing> audio_processing,
                            std::unique_ptr<AudioProcessingBuilder> ap_builder);
   virtual ~AudioProcessingSimulator();
 
@@ -174,8 +174,8 @@
  protected:
   void ProcessStream(bool fixed_interface);
   void ProcessReverseStream(bool fixed_interface);
-  void CreateAudioProcessor();
-  void DestroyAudioProcessor();
+  void ConfigureAudioProcessor();
+  void DetachAecDump();
   void SetupBuffersConfigsOutputs(int input_sample_rate_hz,
                                   int output_sample_rate_hz,
                                   int reverse_input_sample_rate_hz,
@@ -186,8 +186,7 @@
                                   int reverse_output_num_channels);
 
   const SimulationSettings settings_;
-  std::unique_ptr<AudioProcessing> ap_;
-  std::unique_ptr<AudioProcessingBuilder> ap_builder_;
+  rtc::scoped_refptr<AudioProcessing> ap_;
 
   std::unique_ptr<ChannelBuffer<float>> in_buf_;
   std::unique_ptr<ChannelBuffer<float>> out_buf_;
diff --git a/modules/audio_processing/test/audioproc_float_impl.cc b/modules/audio_processing/test/audioproc_float_impl.cc
index d9a4227..ab395f1 100644
--- a/modules/audio_processing/test/audioproc_float_impl.cc
+++ b/modules/audio_processing/test/audioproc_float_impl.cc
@@ -457,7 +457,10 @@
   }
 }
 
-void PerformBasicParameterSanityChecks(const SimulationSettings& settings) {
+void PerformBasicParameterSanityChecks(
+    const SimulationSettings& settings,
+    bool pre_constructed_ap_provided,
+    bool pre_constructed_ap_builder_provided) {
   if (settings.input_filename || settings.reverse_input_filename) {
     ReportConditionalErrorAndExit(
         !!settings.aec_dump_input_filename,
@@ -624,21 +627,41 @@
           settings.pre_amplifier_gain_factor.has_value(),
       "Error: --pre_amplifier_gain_factor needs --pre_amplifier to be "
       "specified and set.\n");
+
+  ReportConditionalErrorAndExit(
+      pre_constructed_ap_provided && pre_constructed_ap_builder_provided,
+      "Error: The AudioProcessing and the AudioProcessingBuilder cannot both "
+      "be specified at the same time.\n");
+
+  ReportConditionalErrorAndExit(
+      settings.aec_settings_filename && pre_constructed_ap_provided,
+      "Error: The aec_settings_filename cannot be specified when a "
+      "pre-constructed audio processing object is provided.\n");
+
+  ReportConditionalErrorAndExit(
+      settings.aec_settings_filename && pre_constructed_ap_provided,
+      "Error: The print_aec_parameter_values cannot be set when a "
+      "pre-constructed audio processing object is provided.\n");
+
+  if (settings.linear_aec_output_filename && pre_constructed_ap_provided) {
+    std::cout << "Warning: For the linear AEC output to be stored, this must "
+                 "be configured in the AEC that is part of the provided "
+                 "AudioProcessing object."
+              << std::endl;
+  }
 }
 
-}  // namespace
-
-int AudioprocFloatImpl(std::unique_ptr<AudioProcessingBuilder> ap_builder,
-                       int argc,
-                       char* argv[],
-                       absl::string_view input_aecdump,
-                       std::vector<float>* processed_capture_samples) {
+int RunSimulation(rtc::scoped_refptr<AudioProcessing> audio_processing,
+                  std::unique_ptr<AudioProcessingBuilder> ap_builder,
+                  int argc,
+                  char* argv[],
+                  absl::string_view input_aecdump,
+                  std::vector<float>* processed_capture_samples) {
   std::vector<char*> args = absl::ParseCommandLine(argc, argv);
   if (args.size() != 1) {
     printf("%s", kUsageDescription);
     return 1;
   }
-
   // InitFieldTrialsFromString stores the char*, so the char array must
   // outlive the application.
   const std::string field_trials = absl::GetFlag(FLAGS_force_fieldtrials);
@@ -650,13 +673,15 @@
     settings.processed_capture_samples = processed_capture_samples;
     RTC_CHECK(settings.processed_capture_samples);
   }
-  PerformBasicParameterSanityChecks(settings);
+  PerformBasicParameterSanityChecks(settings, !!audio_processing, !!ap_builder);
   std::unique_ptr<AudioProcessingSimulator> processor;
 
   if (settings.aec_dump_input_filename || settings.aec_dump_input_string) {
-    processor.reset(new AecDumpBasedSimulator(settings, std::move(ap_builder)));
+    processor.reset(new AecDumpBasedSimulator(
+        settings, std::move(audio_processing), std::move(ap_builder)));
   } else {
-    processor.reset(new WavBasedSimulator(settings, std::move(ap_builder)));
+    processor.reset(new WavBasedSimulator(settings, std::move(audio_processing),
+                                          std::move(ap_builder)));
   }
 
   processor->Process();
@@ -680,5 +705,24 @@
   return 0;
 }
 
+}  // namespace
+
+int AudioprocFloatImpl(rtc::scoped_refptr<AudioProcessing> audio_processing,
+                       int argc,
+                       char* argv[]) {
+  return RunSimulation(
+      std::move(audio_processing), /*ap_builder=*/nullptr, argc, argv,
+      /*input_aecdump=*/"", /*processed_capture_samples=*/nullptr);
+}
+
+int AudioprocFloatImpl(std::unique_ptr<AudioProcessingBuilder> ap_builder,
+                       int argc,
+                       char* argv[],
+                       absl::string_view input_aecdump,
+                       std::vector<float>* processed_capture_samples) {
+  return RunSimulation(/*audio_processing=*/nullptr, std::move(ap_builder),
+                       argc, argv, input_aecdump, processed_capture_samples);
+}
+
 }  // namespace test
 }  // namespace webrtc
diff --git a/modules/audio_processing/test/audioproc_float_impl.h b/modules/audio_processing/test/audioproc_float_impl.h
index 9a9013c..0687c43 100644
--- a/modules/audio_processing/test/audioproc_float_impl.h
+++ b/modules/audio_processing/test/audioproc_float_impl.h
@@ -24,6 +24,21 @@
 // via the |argv| argument. Pass |processed_capture_samples| to write in it the
 // samples processed on the capture side; if |processed_capture_samples| is not
 // passed, the output file can optionally be specified via the |argv| argument.
+// Any audio_processing object specified in the input is used for the
+// simulation. Note that when the audio_processing object is specified all
+// functionality that relies on using the internal builder is deactivated,
+// since the AudioProcessing object is already created and the builder is not
+// used in the simulation.
+int AudioprocFloatImpl(rtc::scoped_refptr<AudioProcessing> audio_processing,
+                       int argc,
+                       char* argv[]);
+
+// This function implements the audio processing simulation utility. Pass
+// |input_aecdump| to provide the content of an AEC dump file as a string; if
+// |input_aecdump| is not passed, a WAV or AEC input dump file must be specified
+// via the |argv| argument. Pass |processed_capture_samples| to write in it the
+// samples processed on the capture side; if |processed_capture_samples| is not
+// passed, the output file can optionally be specified via the |argv| argument.
 int AudioprocFloatImpl(std::unique_ptr<AudioProcessingBuilder> ap_builder,
                        int argc,
                        char* argv[],
diff --git a/modules/audio_processing/test/wav_based_simulator.cc b/modules/audio_processing/test/wav_based_simulator.cc
index 7179fc3..75946fb 100644
--- a/modules/audio_processing/test/wav_based_simulator.cc
+++ b/modules/audio_processing/test/wav_based_simulator.cc
@@ -56,8 +56,18 @@
 
 WavBasedSimulator::WavBasedSimulator(
     const SimulationSettings& settings,
+    rtc::scoped_refptr<AudioProcessing> audio_processing,
     std::unique_ptr<AudioProcessingBuilder> ap_builder)
-    : AudioProcessingSimulator(settings, std::move(ap_builder)) {}
+    : AudioProcessingSimulator(settings,
+                               std::move(audio_processing),
+                               std::move(ap_builder)) {
+  if (settings_.call_order_input_filename) {
+    call_chain_ = WavBasedSimulator::GetCustomEventChain(
+        *settings_.call_order_input_filename);
+  } else {
+    call_chain_ = WavBasedSimulator::GetDefaultEventChain();
+  }
+}
 
 WavBasedSimulator::~WavBasedSimulator() = default;
 
@@ -89,13 +99,7 @@
 }
 
 void WavBasedSimulator::Process() {
-  if (settings_.call_order_input_filename) {
-    call_chain_ = WavBasedSimulator::GetCustomEventChain(
-        *settings_.call_order_input_filename);
-  } else {
-    call_chain_ = WavBasedSimulator::GetDefaultEventChain();
-  }
-  CreateAudioProcessor();
+  ConfigureAudioProcessor();
 
   Initialize();
 
@@ -120,7 +124,7 @@
     call_chain_index = (call_chain_index + 1) % call_chain_.size();
   }
 
-  DestroyAudioProcessor();
+  DetachAecDump();
 }
 
 bool WavBasedSimulator::HandleProcessStreamCall() {
diff --git a/modules/audio_processing/test/wav_based_simulator.h b/modules/audio_processing/test/wav_based_simulator.h
index 991f1db..3adbe70 100644
--- a/modules/audio_processing/test/wav_based_simulator.h
+++ b/modules/audio_processing/test/wav_based_simulator.h
@@ -23,6 +23,7 @@
 class WavBasedSimulator final : public AudioProcessingSimulator {
  public:
   WavBasedSimulator(const SimulationSettings& settings,
+                    rtc::scoped_refptr<AudioProcessing> audio_processing,
                     std::unique_ptr<AudioProcessingBuilder> ap_builder);
   ~WavBasedSimulator() override;