diff --git a/js/ohms-law/view/CurrentSoundGenerator.js b/js/ohms-law/view/CurrentSoundGenerator.js
index 91a5fb9..2426b62 100644
--- a/js/ohms-law/view/CurrentSoundGenerator.js
+++ b/js/ohms-law/view/CurrentSoundGenerator.js
@@ -7,82 +7,75 @@
  *
  * @author John Blanco
  */
-define( function( require ) {
+define( require => {
   'use strict';
 
   // modules
-  var inherit = require( 'PHET_CORE/inherit' );
-  var ohmsLaw = require( 'OHMS_LAW/ohmsLaw' );
-  var OhmsLawConstants = require( 'OHMS_LAW/ohms-law/OhmsLawConstants' );
-  var SoundClip = require( 'TAMBO/sound-generators/SoundClip' );
+  const ohmsLaw = require( 'OHMS_LAW/ohmsLaw' );
+  const OhmsLawConstants = require( 'OHMS_LAW/ohms-law/OhmsLawConstants' );
+  const SoundClip = require( 'TAMBO/sound-generators/SoundClip' );
 
   // constants
-  var PRE_FADE_TIME = 0.1; // in seconds
-  var FADE_OUT_TIME_CONSTANT = 3; // in seconds, larger values indicate faster fade out, see usage for details
-  var FADE_COMPLETE_OUTPUT_LEVEL = 0.001; // level at which fade out is considered complete and level is set to zero
+  const PRE_FADE_TIME = 0.1; // in seconds
+  const FADE_OUT_TIME_CONSTANT = 3; // in seconds, larger values indicate faster fade out, see usage for details
+  const FADE_COMPLETE_OUTPUT_LEVEL = 0.001; // level at which fade out is considered complete and level is set to zero
 
   // sounds
-  var currentLoopSound = require( 'sound!OHMS_LAW/current-v3-loop.mp3' );
+  const currentLoopSound = require( 'sound!OHMS_LAW/current-v3-loop.mp3' );
 
-  /**
-   * {NumberProperty} currentProperty
-   * @constructor
-   */
-  function CurrentSoundGenerator( currentProperty, options ) {
+  class CurrentSoundGenerator extends SoundClip {
 
-    options = _.extend( {
-      initialOutputLevel: 1
-    }, options );
-    options.loop = true; // must be a loop to work properly
-
-    SoundClip.call( this, currentLoopSound, options );
-    var self = this;
-
-    // @private {number} - max output level, used for fading
-    this.maxOutputLevel = options.initialOutputLevel;
+    /**
+     * {NumberProperty} currentProperty
+     * @constructor
+     */
+    constructor( currentProperty, options ) {
 
-    // countdown timer used to play the current sound for a while, then stop
-    this.fadeCountdownTimer = Number.NEGATIVE_INFINITY;
+      options = _.extend( {
+        initialOutputLevel: 1
+      }, options );
+      options.loop = true; // must be a loop to work properly
 
-    // function to turn loop on/off and update playback rate
-    function updateSoundGeneration( current ) {
+      super( currentLoopSound, options );
 
-      // any change turns on the playback
-      if ( !self.isPlaying ) {
-        self.play();
-      }
-      self.fadeCountdownTimer = PRE_FADE_TIME;
+      // @private {number} - max output level, used for fading
+      this.maxOutputLevel = options.initialOutputLevel;
 
-      // calculate the normalized current value using a logarithmic formula to better handle the large range
-      var normalizedCurrent = Math.log( ( current / 1000 ) / OhmsLawConstants.CURRENT_RANGE.min ) /
-                              Math.log( OhmsLawConstants.CURRENT_RANGE.max / OhmsLawConstants.CURRENT_RANGE.min );
+      // countdown timer used to play the current sound for a while, then stop
+      this.fadeCountdownTimer = Number.NEGATIVE_INFINITY;
 
-      // Calculate the playback rate based on the normalized current.  The formula came from the design document, and
-      // ranges from 0.5 to 2.0 times the default playback rate.
-      var playbackRate = 0.5 + 1.5 * Math.pow( normalizedCurrent, 2 );
+      // function to turn loop on/off and update playback rate
+      const updateSoundGeneration = current => {
 
-      // set the playback rate for all loops
-      self.setPlaybackRate( playbackRate );
-    }
+        // any change turns on the playback
+        if ( !this.isPlaying ) {
+          this.play();
+        }
+        this.fadeCountdownTimer = PRE_FADE_TIME;
 
-    // start the loop playing when the current changes
-    currentProperty.lazyLink( updateSoundGeneration );
+        // calculate the normalized current value using a logarithmic formula to better handle the large range
+        const normalizedCurrent = Math.log( ( current / 1000 ) / OhmsLawConstants.CURRENT_RANGE.min ) /
+                                Math.log( OhmsLawConstants.CURRENT_RANGE.max / OhmsLawConstants.CURRENT_RANGE.min );
 
-    this.disposeCurrentSoundGenerator = function() {
-      currentProperty.unlink( updateSoundGeneration );
-    };
-  }
+        // Calculate the playback rate based on the normalized current.  The formula came from the design document, and
+        // ranges from 0.5 to 2.0 times the default playback rate.
+        const playbackRate = 0.5 + 1.5 * Math.pow( normalizedCurrent, 2 );
 
+        // set the playback rate for all loops
+        this.setPlaybackRate( playbackRate );
+      };
 
-  ohmsLaw.register( 'CurrentSoundGenerator', CurrentSoundGenerator );
+      // start the loop playing when the current changes
+      currentProperty.lazyLink( updateSoundGeneration );
 
-  return inherit( SoundClip, CurrentSoundGenerator, {
+      this.disposeCurrentSoundGenerator = () => { currentProperty.unlink( updateSoundGeneration ); };
+    }
 
     /**
      * @param {number} dt
      * @public
      */
-    step: function( dt ) {
+    step( dt ) {
       if ( this.fadeCountdownTimer > Number.NEGATIVE_INFINITY ) {
 
         // decrement the fade countdown timer
@@ -97,7 +90,7 @@ define( function( require ) {
         else if ( this.fadeCountdownTimer > Number.NEGATIVE_INFINITY ) {
 
           // fading out, calculate the level using the exponential decay formula
-          var level = this.maxOutputLevel * Math.pow( Math.E, FADE_OUT_TIME_CONSTANT * this.fadeCountdownTimer );
+          const level = this.maxOutputLevel * Math.pow( Math.E, FADE_OUT_TIME_CONSTANT * this.fadeCountdownTimer );
           if ( level > FADE_COMPLETE_OUTPUT_LEVEL ) {
             this.setOutputLevel( level );
           }
@@ -109,20 +102,25 @@ define( function( require ) {
           }
         }
       }
-    },
+    }
 
-    reset: function() {
+    reset() {
       if ( this.isPlaying ) {
         this.stop();
       }
       this.fadeCountdownTimer = Number.NEGATIVE_INFINITY;
-    },
+    }
 
     /**
      * @public
      */
-    dispose: function() {
+    dispose() {
       this.disposeCurrentSoundGenerator();
     }
-  } );
+
+  }
+
+  ohmsLaw.register( 'CurrentSoundGenerator', CurrentSoundGenerator );
+
+  return CurrentSoundGenerator;
 } );