Prayer (Kitab Al-Salat): Prayer at Night
Dawud :: Book 5 : Hadith 1328
Narrated Uqbah ibn Amir al-Juhani:
The Prophet (peace_be_upon_him) said: One who recites the Qur'an in a loud voice is like one who gives alms openly; and one who recites the Qur'an quietly is one who gives alms secretly.