diff --git a/open_dubbing/pydub_effects.py b/open_dubbing/pydub_effects.py
index ebbcdc3..644733e 100644
--- a/open_dubbing/pydub_effects.py
+++ b/open_dubbing/pydub_effects.py
@@ -16,22 +16,6 @@
     xrange = range
 
 
-@register_pydub_effect
-def apply_mono_filter_to_each_channel(seg, filter_fn):
-    n_channels = seg.channels
-
-    channel_segs = seg.split_to_mono()
-    channel_segs = [filter_fn(channel_seg) for channel_seg in channel_segs]
-
-    out_data = seg.get_array_of_samples()
-    for channel_i, channel_seg in enumerate(channel_segs):
-        for sample_i, sample in enumerate(channel_seg.get_array_of_samples()):
-            index = (sample_i * n_channels) + channel_i
-            out_data[index] = sample
-
-    return seg._spawn(out_data)
-
-
 @register_pydub_effect
 def normalize(seg, headroom=0.1):
     """