diff --git a/src/spikeanalysis/spike_data.py b/src/spikeanalysis/spike_data.py
index 6290d5d..2412fea 100644
--- a/src/spikeanalysis/spike_data.py
+++ b/src/spikeanalysis/spike_data.py
@@ -432,7 +432,35 @@ def get_waveforms(self, wf_window: tuple = (-40, 41), n_wfs: int = 500):
 
         self._return_to_dir(current_dir)
 
-    def qc_preprocessing(self, idthres: float, rpv: float, sil: float, recurated: bool = False):
+    def get_amplitudes(self, std: float = 2):
+        """
+        function for assessing amplitude distribution.
+
+        Parameters
+        ----------
+        std: float, default: 2
+            The number of standard deviations to use when assessing the desired spread of the data
+        Returns
+        -------
+        None.
+
+        """
+
+        waveforms = self.waveforms
+        n_waveforms = waveforms.shape[1]
+        amplitudes = waveforms.max(axis=3) - waveforms.min(axis=3)
+        max_amplitudes = amplitudes.max(axis=2)
+        mean_amplitudes = max_amplitudes.mean(axis=1)
+        std_amplitudes = max_amplitudes.std(axis=1)
+        z_index = np.zeros((max_amplitudes.shape))
+        for row_index in range(max_amplitudes.shape[0]):
+            z_index[row_index] = (max_amplitudes[row_index] - mean_amplitudes[row_index]) / std_amplitudes[row_index]
+
+        amplitude_index = np.where(np.logical_and(z_index < std, z_index > -std), 1, 0).sum(axis=1) / n_waveforms
+
+        self.amplitude_index = amplitude_index
+
+    def qc_preprocessing(self, idthres: float, rpv: float, sil: float, amp_cutoff: float, recurated: bool = False):
         """
         function for curating data based on qc metrics and refractory periods
 
@@ -484,24 +512,34 @@ def qc_preprocessing(self, idthres: float, rpv: float, sil: float, recurated: bo
                     self.refractory_period_violations = np.load("refractory_period_violations.npy")
                 except FileNotFoundError:
                     raise Exception("refractory period violations not calculated")
+            try:
+                _ = self.amplitude_index
+            except AttributeError:
+                try:
+                    self.amplitude_index = np.load("amplitude_distribution.npy")
+                except FileNotFoundError:
+                    raise Exception("ampltiude scores not calculated")
 
             assert len(self.silhouette_scores) == len(self.isolation_distances), "Qc metrics should be same length"
             assert len(self.silhouette_scores) == len(
                 self.refractory_period_violations
             ), "Refractory period violations should be same length as qc"
+            assert len(self.amplitude_index) == len(self.silhouette_scores), "amplitudes scores must be the same length"
 
             iso_d_thres = np.where(self.isolation_distances > idthres, True, False)
             sil_thres = np.where(self.silhouette_scores > sil, True, False)
             rpv_thres = np.where(self.refractory_period_violations < rpv, True, False)
-
+            amp_thres = np.where(self.amplitude_index > amp_cutoff, True, False)
             threshold = np.logical_and(iso_d_thres, sil_thres)
             threshold = np.logical_and(threshold, rpv_thres)
+            threshold = np.logical_and(threshold, amp_thres)
 
             self._qc_threshold = threshold
 
             self._isolation_threshold = idthres
             self._sil_threshold = sil
             self._rpv = rpv
+            self._amp_cutoff = amp_cutoff
 
             if self.CACHING:
                 np.save("qc_threshold.npy", threshold)
@@ -510,6 +548,7 @@ def qc_preprocessing(self, idthres: float, rpv: float, sil: float, recurated: bo
                 print("Current qc_preprocessing values led to 0 units.")
                 print(f"Iso: {np.sum(iso_d_thres)}, sil: {np.sum(sil)}")
                 print(f"RPV: {np.sum(rpv)}")
+                print(f"amp cutoff: {np.sum(amp_thres)}")
 
         self._return_to_dir(current_dir)
 
@@ -524,7 +563,8 @@ def set_qc(self):
             threshold = self._qc_threshold
         except AttributeError:
             raise Exception(
-                f"Must run qc functions first ('generate_pcs', 'generate_qcmetrics', 'refractory_violation')"
+                f"Must run qc functions first ('generate_pcs', 'generate_qcmetrics', 'refractory_violation'"
+                f"'get_amplitudes') "
             )
 
         self._cids = self._cids[threshold]