diff --git a/simulation/cic_filter/cic_filter_comb_main.py b/simulation/cic_filter/cic_filter_comb_main.py
index ae745e9..8d2ec2d 100644
--- a/simulation/cic_filter/cic_filter_comb_main.py
+++ b/simulation/cic_filter/cic_filter_comb_main.py
@@ -49,10 +49,9 @@ def compare_crc_filter_combs(length: int, R: int) -> None:
 
     for coefficients in FILTERS:
         # Apply a comb filter to the signal.
-        comb_filter = _create_comb_filter_before_decimation(coefficients, R)
-        cic_filter_decimator = CicFilterDecimator(R=1,
+        cic_filter_decimator = CicFilterDecimator(R=R,
                                                   N=1,
-                                                  comb_filter=comb_filter)
+                                                  comb_filter=coefficients)
         response = cic_filter_decimator.filter(delta, downsampling=False)
 
         # Plot the spectrum.
diff --git a/simulation/cic_filter/cic_filter_decimator.py b/simulation/cic_filter/cic_filter_decimator.py
index 94a7e08..c81950b 100644
--- a/simulation/cic_filter/cic_filter_decimator.py
+++ b/simulation/cic_filter/cic_filter_decimator.py
@@ -14,9 +14,11 @@ def __init__(self, R: int, N: int, comb_filter: np.ndarray = None) -> None:
 
         if comb_filter is None:
             comb_filter = np.ones(1)
-        self.comb_filter = comb_filter
+        self.comb_filter = comb_filter.astype(np.float64)
         self.num_comb_filter_taps = len(comb_filter)
-        self.comb_filter_diff = self._create_comb_filter_diff(comb_filter)
+        # Scale the filter to its length.
+        self.comb_filter /= np.mean(self.comb_filter)
+        self.comb_filter_diff = self._create_comb_filter_diff(self.comb_filter)
 
     def filter(self,
                signal: np.ndarray,