diff --git a/scripts/_modulate.lua b/scripts/_modulate.lua
new file mode 100644
index 0000000000..353b6718aa
--- /dev/null
+++ b/scripts/_modulate.lua
@@ -0,0 +1,25 @@
+ardour { ["type"] = "Snippet", name = "Modulation Test" }
+
+function factory () return function ()
+	local route = Session:get_remote_nth_route(0)
+	assert (route)
+	local pi = route:nth_plugin(0):to_insert()
+	assert (not pi:isnil())
+	-- this test is for x42-eq .. port 3 is "gain"
+	print (pi:load_modulation_script ([[
+	function dsp_modulate(ctrl, bufs, n_samples, offset, start)
+		cnt = cnt or 0
+		cnt = cnt + n_samples
+		local sr = Session:nominal_frame_rate ()
+		if cnt > sr then cnt = cnt - sr end
+		--local gain = ctrl:at (Evoral.Parameter (ARDOUR.AutomationType.PluginAutomation, 0, 3)):to_automationcontrol():to_plugincontrol()
+		--assert (gain)
+		local a = ARDOUR.DSP.fast_coefficient_to_dB (ARDOUR.DSP.compute_peak(bufs:get_audio(0):data(offset), n_samples, 0)) + 10
+		a = math.min (20, math.max(-20, a))
+		--gain:modulate_to (5 * math.sin (math.pi * cnt / sr) - a)
+		ARDOUR.LuaAPI.modulate_to (ctrl, 3, 5 * math.sin (math.pi * cnt / sr) - a)
+	end
+	]]
+	))
+
+end end