diff --git a/style_bert_vits2/models/hyper_parameters.py b/style_bert_vits2/models/hyper_parameters.py
index 827ce6d..df31573 100644
--- a/style_bert_vits2/models/hyper_parameters.py
+++ b/style_bert_vits2/models/hyper_parameters.py
@@ -38,7 +38,7 @@ class HyperParametersTrain(BaseModel):
 
 
 class HyperParametersData(BaseModel):
-    use_jp_extra: bool = True
+    use_jp_extra: bool = False  # このフィールドが存在しない旧モデルとの互換性のために False をデフォルト値とする
     training_files: str = "Data/Dummy/train.list"
     validation_files: str = "Data/Dummy/val.list"
     max_wav_value: float = 32768.0