diff --git a/mtuq/process_data.py b/mtuq/process_data.py
index d5d194f9..125b1a48 100644
--- a/mtuq/process_data.py
+++ b/mtuq/process_data.py
@@ -317,6 +317,11 @@ def __init__(self,
             self.window_length = window_length
             _window_warnings(window_type, window_length)
 
+        elif self.window_type == 'synthetic':
+            # window type for synthetic examples
+            assert window_length > 0.
+            self.window_length = window_length
+
         else:
             raise ValueError('Bad parameter: window_type')
 
@@ -704,6 +709,14 @@ def __call__(self, traces, station=None, origin=None, overwrite=False):
                 starttime += float(origin.time)
                 endtime += float(origin.time)
 
+            elif self.window_type == 'synthetic':
+                # window type for synthetic examples
+                # waveform starts at 0.0
+                starttime = 0.0
+                endtime = starttime + self.window_length
+                starttime += float(origin.time)
+                endtime += float(origin.time)
+
             else:
                 starttime = trace.stats.starttime
                 endtime = trace.stats.endtime