diff --git a/_subsections/sec03/lesson-16.org b/_subsections/sec03/lesson-16.org
index ce23fc8..4b65e4a 100644
--- a/_subsections/sec03/lesson-16.org
+++ b/_subsections/sec03/lesson-16.org
@@ -17,3 +17,80 @@
    2. set all node children process to false
       - Node function =get_children= will get them all3
       - iterate through them and =set_process(false)=
+
+** sound
+*** import pane
+- the scene panel on the upper left has an Import pane
+        #+ATTR_HTML: :width 600px
+          file:../../../_share/media/albert/img/section03/S03_L16_E01.png
+
+- this allows you to see details of items in the filesystem
+        #+ATTR_HTML: :width 400px
+          file:../../../_share/media/albert/img/section03/S03_L16_E03.png
+
+*** changing details of imported items
+1. make whatever changes you want, e.g. turn on "Loop"
+2. then click the Reimport button
+
+        #+ATTR_HTML: :width 400px
+          file:../../../_share/media/albert/img/section03/S03_L16_E04.png
+
+*** audio nodes
+- Node->Node2D->AudioListener2D
+  - overrides location sounds are heard from
+
+- Node->Node2D->AudioStreamPlayer2D
+  - plays positionnal sound in 2D space
+
+- Node->AudioStreamPlayer
+  - simple audio player
+    - Playing: plays in the *GAME EDITOR*
+    - Autoplay: plays as soon as it is loaded into the scene tree
+
+*** create background music
+- add new Audio node to the scene panel on the Game scene
+  - use AudioStreamPlayer bc we don't care about position
+
+- drag the audio file into Audio node->Inspector->AudioStreamPLayer->Stream
+
+        #+ATTR_HTML: :width 600px
+          file:../../../_share/media/albert/img/section03/S03_L16_E05.png
+
+  - you'll be able to see it when it's loaded
+          #+ATTR_HTML: :width 600px
+            file:../../../_share/media/albert/img/section03/S03_L16_E06.png
+
+- set Autoplay to "ON"
+
+*** add effects
+- use AudioStreamPlayer2D bc it has positioning
+- CMD+drag the AudioStreamPlayer2D node to the game.gd script so we can play it
+- call the effect when something happens (e.g. a gem hits the panel)
+- find the position of where the even happens "area.position"
+ #+BEGIN_SRC gdscript
+ audio_stream_player_2d.position = area.position
+ audio_stream_player_2d.play()
+ #+END_SRC
+
+*** add game over sound
+- first make sure no other sound such as effects sounds are playing.
+- call "stop()" on all such nodes
+    #+BEGIN_SRC gdscript
+    audio_stream_player_2d.stop()
+    #+END_SRC
+
+- load the game over sounds using "preload"
+  - CMD+drag the sound file from the filesystem to the game.gd script
+  - godot will automatically create a constant with the file name
+  - godot will also set that file to "preload" with the appropriate file path
+
+- set the =stream= property of =audio_stream_player_2d= to the preloaded sound and play it
+
+    #+BEGIN_SRC gdscript
+    audio_stream_player_2d.stream = EXPLODE
+    audio_stream_player_2d.play()
+    #+END_SRC
+
+- put all this into a function and add it to the game_over function
+
+