diff --git a/vocoder/hifigan/inference.py b/vocoder/hifigan/inference.py
index ffbe83d..4405f41 100644
--- a/vocoder/hifigan/inference.py
+++ b/vocoder/hifigan/inference.py
@@ -19,12 +19,14 @@ def load_checkpoint(filepath, device):
     return checkpoint_dict
 
 
-def load_model(weights_fpath, config_fpath="./vocoder/hifigan/config_16k.json", verbose=True):
+def load_model(weights_fpath, config_fpath, verbose=True):
     global generator, _device, output_sample_rate
 
     if verbose:
         print("Building hifigan")
 
+    if config_fpath == None:
+        config_fpath = "./vocoder/hifigan/config_16k_.json"
     with open(config_fpath) as f:
         data = f.read()
     json_config = json.loads(data)