diff --git a/index.bs b/index.bs
index 1568cec9d..27fa43165 100644
--- a/index.bs
+++ b/index.bs
@@ -3480,7 +3480,7 @@ is called on.
         factory method).
 
         1. If <var>k</var> is the name of an {{AudioParam}} on this
-            interface, set the {{AudioParam/value}}
+            interface, then if <var>v</var> is of a [=numeric type=], set the {{AudioParam/value}}
             attribute of this {{AudioParam}} to <var>v</var>.
 
         2. Else if <var>k</var> is the name of an attribute on this
@@ -4248,8 +4248,9 @@ Attributes</h4>
             {{DynamicsCompressorNode/threshold}},
             {{DynamicsCompressorNode/knee}},
             {{DynamicsCompressorNode/ratio}},
-            {{DynamicsCompressorNode/attack}}, and
-            {{DynamicsCompressorNode/release}}
+            {{DynamicsCompressorNode/attack}},
+            {{DynamicsCompressorNode/release}}, and
+            {{DynamicsCompressorNode/makeupGain}}
             MUST be "{{AutomationRate/k-rate}}".  <span
             class="synchronous">An {{InvalidStateError}}
             must be thrown if the rate is changed to
@@ -7886,6 +7887,27 @@ macros:
     tail-time-notes:  This node has a <a>tail-time</a> such that this node continues to output non-silent audio with zero input due to the look-ahead delay.
 </pre>
 
+<xmp class="idl">
+enum MakeupGainOptions {
+    "automatic"
+};
+</xmp>
+
+<div class="enum-description">
+    <table class="simple" dfn-type=enum-value dfn-for="MakeupGainOptions">
+        <caption>{{MakeupGainOptions}} Enumeration description</caption>
+        <thead>
+            <tr>
+                <th>Enum Value</th><th>Description</th>
+        <tbody>
+            <tr>
+                <td>
+                    "<dfn>automatic</dfn>"
+                <td>
+                    Set the makeup gain as described in [=Computing the makeup gain=].
+    </table>
+</div>
+
 <xmp class="idl">
 [Exposed=Window]
 interface DynamicsCompressorNode : AudioNode {
@@ -7897,6 +7919,7 @@ interface DynamicsCompressorNode : AudioNode {
     readonly attribute float reduction;
     readonly attribute AudioParam attack;
     readonly attribute AudioParam release;
+    readonly attribute AudioParam makeupGain;
 };
 </xmp>
 
@@ -7907,13 +7930,26 @@ Constructors</h4>
     : <dfn>DynamicsCompressorNode(context, options)</dfn>
     ::
 
+        Let <dfn attribute for="DynamicsCompressorNode">[[internal reduction]]</dfn>
+        be a private slot on <var>this</var>, that holds a floating point number, in
+        decibels. Set {{[[internal reduction]]}} to 0.0.
+
+        Let <dfn attribute for="DynamicsCompressorNode">[[automatic
+        makeup gain]]</dfn> be a private slot on <var>this</var>, that
+        holds a boolean. Set {{[[automatic makeup gain]]}} to `true`
+        if the {{DynamicsCompressorOptions/makeupGain}} option is
+        "{{MakeupGainOptions/automatic}}" or unspecified, otherwise set
+        it to `false`.
+
         <pre class=include>
             path: audionode-init.include
         </pre>
 
-        Let <dfn attribute for="DynamicsCompressorNode">[[internal reduction]]</dfn>
-        be a private slot on <var>this</var>, that holds a floating point number, in
-        decibels. Set {{[[internal reduction]]}} to 0.0.
+        If {{[[automatic makeup gain]]}} is `true`, set the internal slot
+        {{AudioParam/[[current value]]}} of
+        {{DynamicsCompressorNode/makeupGain}} to the return value of
+        <a>computing the makeup gain</a>, <a
+        href="#linear-to-decibel">converted to decibel</a>.
 
         <pre class=argumentdef for="DynamicsCompressorNode/constructor()">
             context: The {{BaseAudioContext}} this new {{DynamicsCompressorNode}} will be <a href="#associated">associated</a> with.
@@ -7954,6 +7990,29 @@ Attributes</h4>
             rate-notes: Has [=automation rate constraints=]
         </pre>
 
+    : <dfn>makeupGain</dfn>
+    ::
+        The decibel value of the makeup gain applied to the signal. If
+        {{[[automatic makeup gain]]}} is `true`, this {{AudioParam}}
+        cannot be modified; <span class="synchronous">an
+        {{InvalidStateError}} MUST be thrown if its
+        {{AudioParam/value}} attribute is set, if any [=automation
+        method=], {{AudioParam/cancelScheduledValues()}}, or
+        {{AudioParam/cancelAndHoldAtTime()}} is called on it, or if an
+        {{AudioNode}} is connected to it</span>.
+
+        <pre class=include>
+        path: audioparam.include
+        macros:
+            default: 0
+            min: <a>most-negative-single-float</a>
+            min-notes: Approximately -3.4028235e38
+            max: \(\approx 771\)
+            max-notes: This value is approximately \(20\ \log_{10} \mathrm{FLT\_MAX}\) where FLT_MAX is the largest {{float}} value.
+            rate: "{{AutomationRate/k-rate}}"
+            rate-notes: Has [=automation rate constraints=]
+        </pre>
+
     : <dfn>ratio</dfn>
     ::
         The amount of dB change in input for a 1 dB change in output.
@@ -8017,6 +8076,7 @@ constructing the node.
 dictionary DynamicsCompressorOptions : AudioNodeOptions {
     float attack = 0.003;
     float knee = 30;
+    (float or MakeupGainOptions) makeupGain = "automatic";
     float ratio = 12;
     float release = 0.25;
     float threshold = -24;
@@ -8028,19 +8088,25 @@ Dictionary {{DynamicsCompressorOptions}} Members</h5>
 
 <dl dfn-type=dict-member dfn-for="DynamicsCompressorOptions">
     : <dfn>attack</dfn>
-    :: The initial value for the {{DynamicsCompressorNode/attack}} AudioParam.
+    :: The initial value for the {{DynamicsCompressorNode/attack}} {{AudioParam}}.
 
     : <dfn>knee</dfn>
-    :: The initial value for the {{DynamicsCompressorNode/knee}} AudioParam.
+    :: The initial value for the {{DynamicsCompressorNode/knee}} {{AudioParam}}.
+
+    : <dfn>makeupGain</dfn>
+    :: The initial value for the {{DynamicsCompressorNode/makeupGain}}
+         {{AudioParam}}. If set to "{{MakeupGainOptions/automatic}}", the
+         makeup gain will be calculated as described in [=Computing the
+         makeup gain=].
 
     : <dfn>ratio</dfn>
-    :: The initial value for the {{DynamicsCompressorNode/ratio}} AudioParam.
+    :: The initial value for the {{DynamicsCompressorNode/ratio}} {{AudioParam}}.
 
     : <dfn>release</dfn>
-    :: The initial value for the {{DynamicsCompressorNode/release}} AudioParam.
+    :: The initial value for the {{DynamicsCompressorNode/release}} {{AudioParam}}.
 
     : <dfn>threshold</dfn>
-    :: The initial value for the {{DynamicsCompressorNode/threshold}} AudioParam.
+    :: The initial value for the {{DynamicsCompressorNode/threshold}} {{AudioParam}}.
 </dl>
 
 <h4 id="DynamicsCompressorOptions-processing">
@@ -8142,6 +8208,13 @@ values. Those values persist accros invocation of this algorithm.
         sample-rate of the {{BaseAudioContext}} this
         {{DynamicsCompressorNode}} is <a href="#associated">associated</a> with.
 
+    1. Let <var>makeup gain</var> be the return value of <a>computing
+        the makeup gain</a> if {{[[automatic makeup gain]]}} is `true`.
+        Otherwise, let <var>makeup gain</var> have the value of
+        {{DynamicsCompressorNode/makeupGain}}, [=decibels to linear gain
+        unit|converted to linear units=] and sampled at the time of
+        processing (as a <a>k-rate</a> parameter).
+
     1. Let <var>detector average</var> be the value of the slot {{[[detector average]]}}.
 
     1. Let <var>compressor gain</var> be the value of the slot {{[[compressor gain]]}}.
@@ -8183,8 +8256,7 @@ values. Those values persist accros invocation of this algorithm.
             to <var>compressor gain</var>.
 
         9. Compute <var>reduction gain</var> to be <var>compressor
-            gain</var> multiplied by the return value of <a>computing the
-            makeup gain</a>.
+            gain</var> multiplied by <var>makeup gain</var>.
 
         10. Compute <var>metering gain</var> to be <var>reduction gain</var>, <a href="#linear-to-decibel">converted to
             decibel</a>.
@@ -8200,6 +8272,12 @@ values. Those values persist accros invocation of this algorithm.
 
         Note: This step makes the metering gain update once per block, at the
         end of the block processing.
+
+    1. If {{[[automatic makeup gain]]}} is `true`, <a>atomically</a> set
+        the internal slot {{AudioParam/[[current value]]}} of
+        {{DynamicsCompressorNode/makeupGain}} to the value of
+        <var>makeup gain</var>, <a href="#linear-to-decibel">converted to
+        decibel</a>.
 </div>
 
 The makeup gain is a fixed gain stage that only depends on ratio,