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diff --git a/testing/web-platform/tests/webaudio/the-audio-api/the-audioparam-interface/audioparam-connect-audioratesignal.html b/testing/web-platform/tests/webaudio/the-audio-api/the-audioparam-interface/audioparam-connect-audioratesignal.html
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+++ b/testing/web-platform/tests/webaudio/the-audio-api/the-audioparam-interface/audioparam-connect-audioratesignal.html
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+<!DOCTYPE html>
+<!--
+Tests that an audio-rate signal (AudioNode output) can be connected to an
+AudioParam.  Specifically, this tests that an audio-rate signal coming from an
+AudioBufferSourceNode playing an AudioBuffer containing a specific curve can be
+connected to an AudioGainNode's .gain attribute (an AudioParam).  Another
+AudioBufferSourceNode will be the audio source having its gain changed.  We load
+this one with an AudioBuffer containing a constant value of 1.  Thus it's easy
+to check that the resultant signal should be equal to the gain-scaling curve.
+-->
+<html>
+  <head>
+    <title>
+      audioparam-connect-audioratesignal.html
+    </title>
+    <script src="/resources/testharness.js"></script>
+    <script src="/resources/testharnessreport.js"></script>
+    <script src="/webaudio/resources/audit-util.js"></script>
+    <script src="/webaudio/resources/audit.js"></script>
+  </head>
+  <body>
+    <script id="layout-test-code">
+      let audit = Audit.createTaskRunner();
+
+      let sampleRate = 44100.0;
+      let lengthInSeconds = 1;
+
+      let context = 0;
+      let constantOneBuffer = 0;
+      let linearRampBuffer = 0;
+
+      function checkResult(renderedBuffer, should) {
+        let renderedData = renderedBuffer.getChannelData(0);
+        let expectedData = linearRampBuffer.getChannelData(0);
+        let n = renderedBuffer.length;
+
+        should(n, 'Rendered signal length').beEqualTo(linearRampBuffer.length);
+
+        // Check that the rendered result exactly matches the buffer used to
+        // control gain.  This is because we're changing the gain of a signal
+        // having constant value 1.
+        let success = true;
+        for (let i = 0; i < n; ++i) {
+          if (renderedData[i] != expectedData[i]) {
+            success = false;
+            break;
+          }
+        }
+
+        should(
+            success,
+            'Rendered signal exactly matches the audio-rate gain changing signal')
+            .beTrue();
+      }
+
+      audit.define('test', function(task, should) {
+        let sampleFrameLength = sampleRate * lengthInSeconds;
+
+        // Create offline audio context.
+        context = new OfflineAudioContext(1, sampleFrameLength, sampleRate);
+
+        // Create buffer used by the source which will have its gain controlled.
+        constantOneBuffer = createConstantBuffer(context, sampleFrameLength, 1);
+
+        // Create buffer used to control gain.
+        linearRampBuffer = createLinearRampBuffer(context, sampleFrameLength);
+
+        // Create the two sources.
+
+        let constantSource = context.createBufferSource();
+        constantSource.buffer = constantOneBuffer;
+
+        let gainChangingSource = context.createBufferSource();
+        gainChangingSource.buffer = linearRampBuffer;
+
+        // Create a gain node controlling the gain of constantSource and make
+        // the connections.
+        let gainNode = context.createGain();
+
+        // Intrinsic baseline gain of zero.
+        gainNode.gain.value = 0;
+
+        constantSource.connect(gainNode);
+        gainNode.connect(context.destination);
+
+        // Connect an audio-rate signal to control the .gain AudioParam.
+        // This is the heart of what is being tested.
+        gainChangingSource.connect(gainNode.gain);
+
+        // Start both sources at time 0.
+        constantSource.start(0);
+        gainChangingSource.start(0);
+
+        context.startRendering().then(buffer => {
+          checkResult(buffer, should);
+          task.done();
+        });
+      });
+
+      audit.run();
+    </script>
+  </body>
+</html>