diff --git a/tupak/detector.py b/tupak/detector.py
index a78edfa7e287f4465d5bad6d7a3e86f057bdfbcd..160b6ab74753aacea77f1016cfd777c288bb918f 100644
--- a/tupak/detector.py
+++ b/tupak/detector.py
@@ -367,7 +367,6 @@ class Interferometer(object):
             strain = tupak.utils.read_frame_file(
                 frame_file, t1=epoch, t2=epoch+duration, channel=channel_name, resample=sampling_frequency)
             frequency_domain_strain, frequencies = tupak.utils.process_strain_data(strain, **kwargs)
-            frequencies = utils.create_frequency_series(sampling_frequency, duration)
             self.power_spectral_density = PowerSpectralDensity(
                 frame_file=frame_file, channel_name=channel_name, epoch=epoch, **kwargs)
         else: