Praying Out Loud By Yourself
Many sahabah used to do it. Prophet Muhammad (SAW) used to listen to the recitation when he (SAW) used to walk in the streets at night. One night when Prophet (SAW) was walking in front of the house of Abu Musa Ashaari (RA), he (SAW) heard him (RA) reciting during salah. He (SAW) stayed there for a little while to listen to this recitation. The following morning after Fajr, he (SAW) praised Abu Musa Ashaari (RA). Narrated By Abu Musa: That the Prophet said to him’ “O Abu Musa! You have been given one of the musical wind-instruments of the family of David.” Sahih Bukhari Volume 006, Book 061, Hadith Number 568.
I believe this was tahajjud. And anyway we wouldn’t base this off hadith