docs: correct lineage wording (fine-tuned from closest-language base)

README.md

@@ -17,7 +17,7 @@ tags:
 
 # pipertts_en-US_miro
 
-This is a text-to-speech voice model for **American English**. The voice is **Miro**, a male voice. It uses the Piper VITS architecture, exported to ONNX for CPU inference. It was built by voice conversion from the base voice `pipertts_en-GB_miro`.
+This is a text-to-speech voice model for **American English**. The voice is **Miro**, a male voice. It uses the Piper VITS architecture, exported to ONNX for CPU inference. It was fine-tuned from the base voice `pipertts_en-GB_miro`, the closest available language for this voice.
 
 ## How to use