What is the key to the better ASR performance of the 1.6.0 version of the Conformer-Transducer-Large model?
Hello, thanks for the great and helpful toolkit! 

As said in [page](https://catalog.ngc.nvidia.com/orgs/nvidia/teams/nemo/models/stt_en_conformer_transducer_large), the 1.6.0 version of the Conformer-Transducer-Large model has much better word error rate performance on Librispeech than the version 1.4.0 (3.6/1.7 vs 4.3/1.9). 

Could you please tell me the key to the better word error rate? Is it the training dataset, the model config or the training recipe?

Many Thanks!