Before revision:  We compress the output vocabulary of the end-to-end ASR  system using linguistically meaningful reductions and then reconstruct the original vocabulary using a standalone module.
After revision:  We compress the output vocabulary of the end-to-end ASR systems for phonetic languages. By identifying sets of acoustically similar graphemes in these languages, we first reduce the output alphabet of the ASR system using linguistically meaningful reductions and then reconstruct the original vocabulary using a standalone module.