diff --git a/tupak/gw/detector.py b/tupak/gw/detector.py
index 824d45729172cf11d1d6373f487a4b667bc7ac20..77c04c6295896aa9217648286d5beda40445a74d 100644
--- a/tupak/gw/detector.py
+++ b/tupak/gw/detector.py
@@ -756,7 +756,8 @@ class PowerSpectralDensity(object):
         white_noise, frequencies = utils.create_white_noise(sampling_frequency, duration)
         interpolated_power_spectral_density = self.power_spectral_density_interpolated(frequencies)
         frequency_domain_strain = interpolated_power_spectral_density ** 0.5 * white_noise
-        frequency_domain_strain[(frequencies < min(self.frequencies)) | (frequencies > max(self.frequencies))] = 0
+        out_of_bounds = (frequencies < min(self.frequencies)) | (frequencies > max(self.frequencies))
+        frequency_domain_strain[out_of_bounds] = 0 * (1 + 1j)
         return frequency_domain_strain, frequencies