--- a/dom/media/webaudio/AudioBufferSourceNode.cpp
+++ b/dom/media/webaudio/AudioBufferSourceNode.cpp
@@ -592,18 +592,18 @@ public:
 AudioBufferSourceNode::AudioBufferSourceNode(AudioContext* aContext)
   : AudioScheduledSourceNode(aContext,
                              2,
                              ChannelCountMode::Max,
                              ChannelInterpretation::Speakers)
   , mLoopStart(0.0)
   , mLoopEnd(0.0)
   // mOffset and mDuration are initialized in Start().
-  , mPlaybackRate(new AudioParam(this, PLAYBACKRATE, 1.0f, "playbackRate"))
-  , mDetune(new AudioParam(this, DETUNE, 0.0f, "detune"))
+  , mPlaybackRate(new AudioParam(this, PLAYBACKRATE, "playbackRate", 1.0f))
+  , mDetune(new AudioParam(this, DETUNE, "detune", 0.0f))
   , mLoop(false)
   , mStartCalled(false)
 {
   AudioBufferSourceNodeEngine* engine = new AudioBufferSourceNodeEngine(this, aContext->Destination());
   mStream = AudioNodeStream::Create(aContext, engine,
                                     AudioNodeStream::NEED_MAIN_THREAD_FINISHED,
                                     aContext->Graph());
   engine->SetSourceStream(mStream);

--- a/dom/media/webaudio/AudioParam.cpp
+++ b/dom/media/webaudio/AudioParam.cpp
@@ -30,23 +30,27 @@ NS_IMPL_CYCLE_COLLECTION_TRACE_WRAPPERCA
 NS_IMPL_CYCLE_COLLECTING_NATIVE_ADDREF(AudioParam)
 NS_IMPL_CYCLE_COLLECTING_NATIVE_RELEASE(AudioParam)
 
 NS_IMPL_CYCLE_COLLECTION_ROOT_NATIVE(AudioParam, AddRef)
 NS_IMPL_CYCLE_COLLECTION_UNROOT_NATIVE(AudioParam, Release)
 
 AudioParam::AudioParam(AudioNode* aNode,
                        uint32_t aIndex,
+                       const char* aName,
                        float aDefaultValue,
-                       const char* aName)
+                       float aMinValue,
+                       float aMaxValue)
   : AudioParamTimeline(aDefaultValue)
   , mNode(aNode)
   , mName(aName)
   , mIndex(aIndex)
   , mDefaultValue(aDefaultValue)
+  , mMinValue(aMinValue)
+  , mMaxValue(aMaxValue)
 {
 }
 
 AudioParam::~AudioParam()
 {
   DisconnectFromGraphAndDestroyStream();
 }
 

--- a/dom/media/webaudio/AudioParam.h
+++ b/dom/media/webaudio/AudioParam.h
@@ -22,18 +22,20 @@ namespace dom {
 class AudioParam final : public nsWrapperCache,
                          public AudioParamTimeline
 {
   virtual ~AudioParam();
 
 public:
   AudioParam(AudioNode* aNode,
              uint32_t aIndex,
+             const char* aName,
              float aDefaultValue,
-             const char* aName);
+             float aMinValue = -std::numeric_limits<float>::infinity(),
+             float aMaxValue = std::numeric_limits<float>::infinity());
 
   NS_IMETHOD_(MozExternalRefCountType) AddRef(void);
   NS_IMETHOD_(MozExternalRefCountType) Release(void);
   NS_DECL_CYCLE_COLLECTION_SCRIPT_HOLDER_NATIVE_CLASS(AudioParam)
 
   AudioContext* GetParentObject() const
   {
     return mNode->Context();
@@ -160,16 +162,26 @@ public:
     aName.AssignASCII(mName);
   }
 
   float DefaultValue() const
   {
     return mDefaultValue;
   }
 
+  float MinValue() const
+  {
+    return mMinValue;
+  }
+
+  float MaxValue() const
+  {
+    return mMaxValue;
+  }
+
   const nsTArray<AudioNode::InputNode>& InputNodes() const
   {
     return mInputNodes;
   }
 
   void RemoveInputNode(uint32_t aIndex)
   {
     mInputNodes.RemoveElementAt(aIndex);
@@ -239,15 +251,17 @@ private:
   // For every InputNode, there is a corresponding entry in mOutputParams of the
   // InputNode's mInputNode.
   nsTArray<AudioNode::InputNode> mInputNodes;
   const char* mName;
   // The input port used to connect the AudioParam's stream to its node's stream
   RefPtr<MediaInputPort> mNodeStreamPort;
   const uint32_t mIndex;
   const float mDefaultValue;
+  const float mMinValue;
+  const float mMaxValue;
 };
 
 } // namespace dom
 } // namespace mozilla
 
 #endif
 

--- a/dom/media/webaudio/BiquadFilterNode.cpp
+++ b/dom/media/webaudio/BiquadFilterNode.cpp
@@ -246,20 +246,22 @@ private:
 
 BiquadFilterNode::BiquadFilterNode(AudioContext* aContext)
   : AudioNode(aContext,
               2,
               ChannelCountMode::Max,
               ChannelInterpretation::Speakers)
   , mType(BiquadFilterType::Lowpass)
   , mFrequency(new AudioParam(this, BiquadFilterNodeEngine::FREQUENCY,
-                              350.f, "frequency"))
-  , mDetune(new AudioParam(this, BiquadFilterNodeEngine::DETUNE, 0.f, "detune"))
-  , mQ(new AudioParam(this, BiquadFilterNodeEngine::Q, 1.f, "Q"))
-  , mGain(new AudioParam(this, BiquadFilterNodeEngine::GAIN, 0.f, "gain"))
+                              "frequency", 350.f,
+                              -(aContext->SampleRate() / 2),
+                              aContext->SampleRate() / 2))
+  , mDetune(new AudioParam(this, BiquadFilterNodeEngine::DETUNE, "detune", 0.f))
+  , mQ(new AudioParam(this, BiquadFilterNodeEngine::Q, "Q", 1.f))
+  , mGain(new AudioParam(this, BiquadFilterNodeEngine::GAIN, "gain", 0.f))
 {
   uint64_t windowID = aContext->GetParentObject()->WindowID();
   BiquadFilterNodeEngine* engine = new BiquadFilterNodeEngine(this, aContext->Destination(), windowID);
   mStream = AudioNodeStream::Create(aContext, engine,
                                     AudioNodeStream::NO_STREAM_FLAGS,
                                     aContext->Graph());
 }
 

--- a/dom/media/webaudio/ConstantSourceNode.cpp
+++ b/dom/media/webaudio/ConstantSourceNode.cpp
@@ -142,17 +142,17 @@ public:
 };
 
 ConstantSourceNode::ConstantSourceNode(AudioContext* aContext)
   : AudioScheduledSourceNode(aContext,
                              1,
                              ChannelCountMode::Max,
                              ChannelInterpretation::Speakers)
   , mOffset(new AudioParam(this, ConstantSourceNodeEngine::OFFSET,
-                           1.0, "offset"))
+                           "offset", 1.0f))
   , mStartCalled(false)
 {
   ConstantSourceNodeEngine* engine = new ConstantSourceNodeEngine(this, aContext->Destination());
   mStream = AudioNodeStream::Create(aContext, engine,
                                     AudioNodeStream::NEED_MAIN_THREAD_FINISHED,
                                     aContext->Graph());
   engine->SetSourceStream(mStream);
   mStream->AddMainThreadListener(this);

--- a/dom/media/webaudio/DelayNode.cpp
+++ b/dom/media/webaudio/DelayNode.cpp
@@ -191,17 +191,18 @@ public:
   int32_t mLeftOverData;
 };
 
 DelayNode::DelayNode(AudioContext* aContext, double aMaxDelay)
   : AudioNode(aContext,
               2,
               ChannelCountMode::Max,
               ChannelInterpretation::Speakers)
-  , mDelay(new AudioParam(this, DelayNodeEngine::DELAY, 0.0f, "delayTime"))
+  , mDelay(new AudioParam(this, DelayNodeEngine::DELAY, "delayTime", 0.0f,
+                          0.f, aMaxDelay))
 {
   DelayNodeEngine* engine =
     new DelayNodeEngine(this, aContext->Destination(),
                         aContext->SampleRate() * aMaxDelay);
   mStream = AudioNodeStream::Create(aContext, engine,
                                     AudioNodeStream::NO_STREAM_FLAGS,
                                     aContext->Graph());
 }

--- a/dom/media/webaudio/DynamicsCompressorNode.cpp
+++ b/dom/media/webaudio/DynamicsCompressorNode.cpp
@@ -183,26 +183,26 @@ private:
 };
 
 DynamicsCompressorNode::DynamicsCompressorNode(AudioContext* aContext)
   : AudioNode(aContext,
               2,
               ChannelCountMode::Explicit,
               ChannelInterpretation::Speakers)
   , mThreshold(new AudioParam(this, DynamicsCompressorNodeEngine::THRESHOLD,
-                              -24.f, "threshold"))
+                              "threshold", -24.f, -100.f, 0.f))
   , mKnee(new AudioParam(this, DynamicsCompressorNodeEngine::KNEE,
-                         30.f, "knee"))
+                         "knee", 30.f, 0.f, 40.f))
   , mRatio(new AudioParam(this, DynamicsCompressorNodeEngine::RATIO,
-                          12.f, "ratio"))
+                          "ratio", 12.f, 1.f, 20.f))
   , mReduction(0)
   , mAttack(new AudioParam(this, DynamicsCompressorNodeEngine::ATTACK,
-                           0.003f, "attack"))
+                           "attack", 0.003f, 0.f, 1.f))
   , mRelease(new AudioParam(this, DynamicsCompressorNodeEngine::RELEASE,
-                            0.25f, "release"))
+                            "release", 0.25f, 0.f, 1.f))
 {
   DynamicsCompressorNodeEngine* engine = new DynamicsCompressorNodeEngine(this, aContext->Destination());
   mStream = AudioNodeStream::Create(aContext, engine,
                                     AudioNodeStream::NO_STREAM_FLAGS,
                                     aContext->Graph());
 }
 
 /* static */ already_AddRefed<DynamicsCompressorNode>

--- a/dom/media/webaudio/GainNode.cpp
+++ b/dom/media/webaudio/GainNode.cpp
@@ -115,17 +115,17 @@ public:
   AudioParamTimeline mGain;
 };
 
 GainNode::GainNode(AudioContext* aContext)
   : AudioNode(aContext,
               2,
               ChannelCountMode::Max,
               ChannelInterpretation::Speakers)
-  , mGain(new AudioParam(this, GainNodeEngine::GAIN, 1.0f, "gain"))
+  , mGain(new AudioParam(this, GainNodeEngine::GAIN, "gain", 1.0f))
 {
   GainNodeEngine* engine = new GainNodeEngine(this, aContext->Destination());
   mStream = AudioNodeStream::Create(aContext, engine,
                                     AudioNodeStream::NO_STREAM_FLAGS,
                                     aContext->Graph());
 }
 
 /* static */ already_AddRefed<GainNode>

--- a/dom/media/webaudio/OscillatorNode.cpp
+++ b/dom/media/webaudio/OscillatorNode.cpp
@@ -408,21 +408,23 @@ public:
 };
 
 OscillatorNode::OscillatorNode(AudioContext* aContext)
   : AudioScheduledSourceNode(aContext,
                              2,
                              ChannelCountMode::Max,
                              ChannelInterpretation::Speakers)
   , mType(OscillatorType::Sine)
-  , mFrequency(new AudioParam(this, OscillatorNodeEngine::FREQUENCY,
-                              440.0f, "frequency"))
-  , mDetune(new AudioParam(this, OscillatorNodeEngine::DETUNE, 0.0f, "detune"))
+  , mFrequency(
+    new AudioParam(this, OscillatorNodeEngine::FREQUENCY, "frequency", 440.0f,
+                   -(aContext->SampleRate() / 2), aContext->SampleRate() / 2))
+  , mDetune(new AudioParam(this, OscillatorNodeEngine::DETUNE, "detune", 0.0f))
   , mStartCalled(false)
 {
+
   OscillatorNodeEngine* engine = new OscillatorNodeEngine(this, aContext->Destination());
   mStream = AudioNodeStream::Create(aContext, engine,
                                     AudioNodeStream::NEED_MAIN_THREAD_FINISHED,
                                     aContext->Graph());
   engine->SetSourceStream(mStream);
   mStream->AddMainThreadListener(this);
 }
 

--- a/dom/media/webaudio/PannerNode.cpp
+++ b/dom/media/webaudio/PannerNode.cpp
@@ -296,22 +296,22 @@ public:
 PannerNode::PannerNode(AudioContext* aContext)
   : AudioNode(aContext,
               2,
               ChannelCountMode::Clamped_max,
               ChannelInterpretation::Speakers)
   // Please keep these default values consistent with PannerNodeEngine::PannerNodeEngine above.
   , mPanningModel(PanningModelType::Equalpower)
   , mDistanceModel(DistanceModelType::Inverse)
-  , mPositionX(new AudioParam(this, PannerNode::POSITIONX, 0., this->NodeType()))
-  , mPositionY(new AudioParam(this, PannerNode::POSITIONY, 0., this->NodeType()))
-  , mPositionZ(new AudioParam(this, PannerNode::POSITIONZ, 0., this->NodeType()))
-  , mOrientationX(new AudioParam(this, PannerNode::ORIENTATIONX, 1., this->NodeType()))
-  , mOrientationY(new AudioParam(this, PannerNode::ORIENTATIONY, 0., this->NodeType()))
-  , mOrientationZ(new AudioParam(this, PannerNode::ORIENTATIONZ, 0., this->NodeType()))
+  , mPositionX(new AudioParam(this, PannerNode::POSITIONX, this->NodeType(), 0.f))
+  , mPositionY(new AudioParam(this, PannerNode::POSITIONY, this->NodeType(), 0.f))
+  , mPositionZ(new AudioParam(this, PannerNode::POSITIONZ, this->NodeType(), 0.f))
+  , mOrientationX(new AudioParam(this, PannerNode::ORIENTATIONX, this->NodeType(), 1.0f))
+  , mOrientationY(new AudioParam(this, PannerNode::ORIENTATIONY, this->NodeType(), 0.f))
+  , mOrientationZ(new AudioParam(this, PannerNode::ORIENTATIONZ, this->NodeType(), 0.f))
   , mVelocity()
   , mRefDistance(1.)
   , mMaxDistance(10000.)
   , mRolloffFactor(1.)
   , mConeInnerAngle(360.)
   , mConeOuterAngle(360.)
   , mConeOuterGain(0.)
 {

--- a/dom/media/webaudio/StereoPannerNode.cpp
+++ b/dom/media/webaudio/StereoPannerNode.cpp
@@ -170,17 +170,17 @@ public:
   AudioParamTimeline mPan;
 };
 
 StereoPannerNode::StereoPannerNode(AudioContext* aContext)
   : AudioNode(aContext,
               2,
               ChannelCountMode::Clamped_max,
               ChannelInterpretation::Speakers)
-  , mPan(new AudioParam(this, StereoPannerNodeEngine::PAN, 0.f, "pan"))
+  , mPan(new AudioParam(this, StereoPannerNodeEngine::PAN, "pan", 0.f, -1.f, 1.f))
 {
   StereoPannerNodeEngine* engine = new StereoPannerNodeEngine(this, aContext->Destination());
   mStream = AudioNodeStream::Create(aContext, engine,
                                     AudioNodeStream::NO_STREAM_FLAGS,
                                     aContext->Graph());
 }
 
 /* static */ already_AddRefed<StereoPannerNode>

--- a/dom/webidl/AudioParam.webidl
+++ b/dom/webidl/AudioParam.webidl
@@ -8,18 +8,20 @@
  *
  * Copyright © 2012 W3C® (MIT, ERCIM, Keio), All Rights Reserved. W3C
  * liability, trademark and document use rules apply.
  */
 
 [Pref="dom.webaudio.enabled"]
 interface AudioParam {
 
-    attribute float value;
-    readonly attribute float defaultValue;
+                    attribute float value;
+    readonly        attribute float defaultValue;
+    readonly        attribute float minValue;
+    readonly        attribute float maxValue;
 
     // Parameter automation. 
     [Throws]
     AudioParam setValueAtTime(float value, double startTime);
     [Throws]
     AudioParam linearRampToValueAtTime(float value, double endTime);
     [Throws]
     AudioParam exponentialRampToValueAtTime(float value, double endTime);

--- a/testing/web-platform/meta/MANIFEST.json
+++ b/testing/web-platform/meta/MANIFEST.json
@@ -32189,16 +32189,20 @@
         "path": "webaudio/the-audio-api/the-audiodestinationnode-interface/idl-test.html",
         "url": "/webaudio/the-audio-api/the-audiodestinationnode-interface/idl-test.html"
       },
       {
         "path": "webaudio/the-audio-api/the-audionode-interface/audionode-connect-return-value.html",
         "url": "/webaudio/the-audio-api/the-audionode-interface/audionode-connect-return-value.html"
       },
       {
+        "path": "webaudio/the-audio-api/the-audioparam-interface/idl-test.html",
+        "url": "/webaudio/the-audio-api/the-audioparam-interface/idl-test.html"
+      },
+      {
         "path": "webaudio/the-audio-api/the-audioparam-interface/retrospective-setValueAtTime.html",
         "url": "/webaudio/the-audio-api/the-audioparam-interface/retrospective-setValueAtTime.html"
       },
       {
         "path": "webaudio/the-audio-api/the-audioparam-interface/setTargetAtTime-after-event-within-block.html",
         "url": "/webaudio/the-audio-api/the-audioparam-interface/setTargetAtTime-after-event-within-block.html"
       },
       {

new file mode 100644
--- /dev/null
+++ b/testing/web-platform/tests/webaudio/the-audio-api/the-audioparam-interface/idl-test.html
@@ -0,0 +1,50 @@
+<!DOCTYPE html>
+<html class="a">
+<head>
+<title>AudioParam IDL Test</title>
+<script src="/resources/testharness.js"></script><script src="/resources/testharnessreport.js"></script><script src="/resources/idlharness.js"></script><script src="/resources/WebIDLParser.js"></script><script src="/webaudio/js/lodash.js"></script><script src="/webaudio/js/vendor-prefixes.js"></script><script src="/webaudio/js/helpers.js"></script><style type="text/css">
+    #audio-param-idl
+    { visibility:hidden; height: 0px;}
+  </style>
+</head>
+<body class="a">
+
+   <pre id="audio-param-idl">interface AudioParam {
+
+                    attribute float value;
+    readonly        attribute float defaultValue;
+    readonly        attribute float minValue;
+    readonly        attribute float maxValue;
+
+    // Parameter automation.
+    void setValueAtTime(float value, double startTime);
+    void linearRampToValueAtTime(float value, double endTime);
+    void exponentialRampToValueAtTime(float value, double endTime);
+
+    // Exponentially approach the target value with a rate having the given time constant.
+    void setTargetAtTime(float target, double startTime, double timeConstant);
+
+    // Sets an array of arbitrary parameter values starting at time for the given duration.
+    // The number of values will be scaled to fit into the desired duration.
+    void setValueCurveAtTime(Float32Array values, double startTime, double duration);
+
+    // Cancels all scheduled parameter changes with times greater than or equal to startTime.
+    void cancelScheduledValues(double startTime);
+
+};</pre>
+
+  <div id="log"></div>
+
+  <script>
+(function() {
+  var idl_array = new IdlArray();
+  idl_array.add_untested_idls(document.getElementById("audio-param-idl").textContent);
+
+  delay_time = (new AudioContext).createDelay().delayTime;
+
+  idl_array.add_objects({AudioParam: ["delay_time"]});
+  idl_array.test();
+})();
+  </script>
+</body>
+</html>

--- a/testing/web-platform/tests/webaudio/the-audio-api/the-delaynode-interface/idl-test.html
+++ b/testing/web-platform/tests/webaudio/the-audio-api/the-delaynode-interface/idl-test.html
@@ -91,18 +91,20 @@ interface AudioNode : EventTarget {
     attribute unsigned long channelCount;
     attribute ChannelCountMode channelCountMode;
     attribute ChannelInterpretation channelInterpretation;
 
 };</pre>
 
    <pre id="audio-param-idl">interface AudioParam {
 
-    attribute float value;
-    readonly attribute float defaultValue;
+                    attribute float value;
+    readonly        attribute float defaultValue;
+    readonly        attribute float minValue;
+    readonly        attribute float maxValue;
 
     // Parameter automation.
     void setValueAtTime(float value, double startTime);
     void linearRampToValueAtTime(float value, double endTime);
     void exponentialRampToValueAtTime(float value, double endTime);
 
     // Exponentially approach the target value with a rate having the given time constant.
     void setTargetAtTime(float target, double startTime, double timeConstant);

--- a/testing/web-platform/tests/webaudio/the-audio-api/the-gainnode-interface/idl-test.html
+++ b/testing/web-platform/tests/webaudio/the-audio-api/the-gainnode-interface/idl-test.html
@@ -90,18 +90,20 @@ interface AudioNode : EventTarget {
     attribute unsigned long channelCount;
     attribute ChannelCountMode channelCountMode;
     attribute ChannelInterpretation channelInterpretation;
 
 };</pre>
 
    <pre id="audio-param-idl">interface AudioParam {
 
-    attribute float value;
-    readonly attribute float defaultValue;
+                    attribute float value;
+    readonly        attribute float defaultValue;
+    readonly        attribute float minValue;
+    readonly        attribute float maxValue;
 
     // Parameter automation.
     void setValueAtTime(float value, double startTime);
     void linearRampToValueAtTime(float value, double endTime);
     void exponentialRampToValueAtTime(float value, double endTime);
 
     // Exponentially approach the target value with a rate having the given time constant.
     void setTargetAtTime(float target, double startTime, double timeConstant);