diff --git a/adhearsion.gemspec b/adhearsion.gemspec
index 4f95fef2..929eb72e 100644
--- a/adhearsion.gemspec
+++ b/adhearsion.gemspec
@@ -35,7 +35,7 @@ Gem::Specification.new do |s|
   s.add_runtime_dependency 'pry'
   s.add_runtime_dependency 'punchblock', ["~> 2.6"]
   s.add_runtime_dependency 'rake'
-  s.add_runtime_dependency 'ruby_speech', ["~> 2.0"]
+  s.add_runtime_dependency 'ruby_speech', ">= 2", "< 4"
   s.add_runtime_dependency 'thor', "~> 0.18.0"
 
   s.add_development_dependency 'aruba', "~> 0.5"