Make TTS a singleton and load directly from the plugin.

project.godot

@@ -19,7 +19,7 @@ run/main_scene="res://scenes/Main.tscn"
 
 [autoload]
 
-Globals="*res://scripts/Globals.gd"
+TTS="*res://addons/godot-tts/TTS.gd"
 
 [editor_plugins]
 

scenes/Main.gd

@@ -6,7 +6,7 @@ extends Node
 
 # Called when the node enters the scene tree for the first time.
 func _ready():
-	Globals.tts.speak("Hello, world.", true)
+	TTS.speak("Hello, world.")
 
 # Called every frame. 'delta' is the elapsed time since the previous frame.
 #func _process(delta):

scripts/Globals.gd

@@ -1,8 +0,0 @@
-extends Node
-
-const TTS = preload("res://addons/godot-tts/TTS.gd")
-var tts
-
-# Called when the node enters the scene tree for the first time.
-func _ready():
-    tts = TTS.new()