> > Otherwise, I certainly voice English /d/.
I happily believe you voice English /d/ as English /d/ is "voiced" by a
native speaker - but that may not mean actual voicing in phonetic terms!
The actual phenomenon of /d/ etc is complex, involving influence on
surrounding sounds, and factors other than pure voice. When a native
speaker thinks they "voice" a /d/, they may in fact be merely producing all
the other concomitant factors which are interpreted as voicing by other
native speakers. Mere native speaker intuition is here not enough.
Peter