[Cartesia] Update the default alias for Cartesia TTS Service

src/pipecat/services/cartesia.py

@@ -84,7 +84,7 @@ class CartesiaTTSService(AudioContextWordTTSService):
         voice_id: str,
         cartesia_version: str = "2024-06-10",
         url: str = "wss://api.cartesia.ai/tts/websocket",
-        model: str = "sonic",
+        model: str = "sonic-2",
         sample_rate: Optional[int] = None,
         encoding: str = "pcm_s16le",
         container: str = "raw",
@@ -311,7 +311,7 @@ class CartesiaHttpTTSService(TTSService):
         *,
         api_key: str,
         voice_id: str,
-        model: str = "sonic",
+        model: str = "sonic-2",
         base_url: str = "https://api.cartesia.ai",
         sample_rate: Optional[int] = None,
         encoding: str = "pcm_s16le",