diff --git a/Software/python/server.py b/Software/python/server.py
index b715f25..33f0d2b 100644
--- a/Software/python/server.py
+++ b/Software/python/server.py
@@ -107,7 +107,7 @@ def controller():
     else:
         sample_interval = D.dt
     base_speed = 0.1
-    iir_taps = np.append(D.num[1:], 0)
+    iir_taps = np.append(D.den[1:], 0)
     fir_taps = np.append(D.num, 0)
     fir_taps = np.concatenate([np.zeros((len(iir_taps) + 1) - len(fir_taps)), fir_taps])