Clarifications on Noise augmentation experiments with Nemo
Hi 
I followed the instructions @ https://github.com/NVIDIA/NeMo/issues/1660 and could successfully train a musan noise augmented nemo ASR model. However, I have few queries:

1. Where does the noise augmented files are stored? Or Are these noise augmented files are simply produced on the fly, as and when needed, and discarded once the job is done (without retaining them)?

2. When I use augmentors during training, does it include original clean files also for training along-with noise augmented files? Or it only uses noise augmented files for training?

3. For the kind of experiments & datasets that we used, we had expected lower WERs with noise augmentation compared to WERs obtained on clean datasets. However the obtained results are other way (noise augmented datasets have 1% higher WER than clean data). This made us to suspect the implementation part of nemo asr training. I have used exactly the same config of audio_augmentations mentioned by @jbalam-nv. There were no errors during training as well. Do you still feel there might be some implementation gaps (which has led to lower WER). Any suggestions on this would be very helpful.

4. I have used musan free sound noise and RIR. Is it fine? or any suggestions on this? 

Thanks a lot,
Manjunath