diff --git a/examples/audio.cpp b/examples/audio.cpp
index aa54d3e1..7d5b144e 100644
--- a/examples/audio.cpp
+++ b/examples/audio.cpp
@@ -7,13 +7,17 @@
 #include <psemek/audio/effect/volume.hpp>
 #include <psemek/audio/effect/fade_in.hpp>
 #include <psemek/audio/effect/fade_out.hpp>
+#include <psemek/audio/effect/compressor.hpp>
 #include <psemek/audio/duplicate.hpp>
 #include <psemek/audio/stereo.hpp>
 #include <psemek/audio/mixer.hpp>
 #include <psemek/app/app.hpp>
 #include <psemek/app/main.hpp>
+#include <psemek/gfx/painter.hpp>
 #include <psemek/util/clock.hpp>
+#include <psemek/util/to_string.hpp>
 #include <psemek/geom/constants.hpp>
+#include <psemek/geom/camera.hpp>
 
 #include <map>
 
@@ -64,7 +68,7 @@ struct audio_app
 	{
 		mixer_ = audio::make_mixer();
 		volume_control_ = audio::volume_stereo(mixer_, 0.5f, 0.5f, 0.1f);
-		engine_.output()->stream(volume_control_);
+		engine_.output()->stream(audio::compressor(volume_control_, audio::from_db(-2.f), 0.95f, 0.002f, 1.f));
 	}
 
 	void on_key_down(SDL_Keycode key) override
@@ -101,6 +105,22 @@ struct audio_app
 		volume_control_->gain_right(0.5f - 0.5f * volume);
 	}
 
+	void present() override
+	{
+		gl::ClearColor(0.8f, 0.8f, 1.f, 1.f);
+		gl::Clear(gl::COLOR_BUFFER_BIT);
+
+		{
+			gfx::painter::text_options opts;
+			opts.x = gfx::painter::x_align::left;
+			opts.y = gfx::painter::y_align::top;
+			opts.scale = 2.f;
+			opts.c = {0, 0, 0, 255};
+		}
+
+		painter_.render(geom::window_camera{width(), height()}.transform());
+	}
+
 private:
 	audio::engine engine_;
 	audio::mixer_ptr mixer_;
@@ -108,6 +128,8 @@ private:
 	std::map<SDL_Keycode, audio::channel_ptr> channels_;
 
 	util::clock<> clock_;
+
+	gfx::painter painter_;
 };
 
 int main()