diff --git a/src/bin/lockin-internal-demo.rs b/src/bin/lockin-internal-demo.rs
index 6acfc36..e36c676 100644
--- a/src/bin/lockin-internal-demo.rs
+++ b/src/bin/lockin-internal-demo.rs
@@ -50,7 +50,7 @@ const APP: () = {
         let (mut stabilizer, _pounder) = hardware::setup(c.core, c.device);
 
         let lockin = Lockin::new(
-            &iir_int::IIRState::default(), // TODO: lowpass, expose
+            &iir_int::IIRState::lowpass(1e-3, 0.707, 2.), // TODO: expose
         );
 
         // Enable ADC/DAC events