diff --git a/modules/core/spk/TTSSpeaker.py b/modules/core/spk/TTSSpeaker.py
index bf92303..25f387d 100644
--- a/modules/core/spk/TTSSpeaker.py
+++ b/modules/core/spk/TTSSpeaker.py
@@ -135,7 +135,7 @@ def from_token(model_id: str, tokens: list) -> "TTSSpeaker":
     @staticmethod
     def from_ref_wav(ref_wav: tuple[int, np.ndarray], text="") -> "TTSSpeaker":
         sr, data = ref_wav
-        assert data.dtype != np.int16, "ref wav must be int16"
+        assert data.dtype == np.int16, f"ref wav must be int16, but got {data.dtype}"
 
         spk = TTSSpeaker.empty()
         spk.add_ref(ref=DcSpkReference(text=text, wav=data.tobytes(), wav_sr=sr))