[Machine] The reading of the Messenger of Allah ﷺ was as much as those in the room could hear while he was in the house.  

كَانَتْ قِرَاءَةُ رَسُولِ اللهِ ﷺ عَلَى قَدْرِ مَا يَسْمَعُهُ مَنْ فِي الْحُجْرَةِ وَهُوَ فِي الْبَيْتِ  

[Machine] He informed him, saying, "I asked Ibn Abbas and said to him, 'How was the night prayer of the Messenger of Allah ﷺ?' He said, 'He used to recite in some of his chambers and his recitation would be heard by those who were outside.'"  

أَخْبَرَهُ قَالَ سَأَلْتُ ابْنَ عَبَّاسٍ فَقُلْتُ كَيْفَ كَانَتْ صَلَاةُ رَسُولِ اللهِ ﷺ بِاللَّيْلِ؟ فَقَالَ كَانَ يَقْرَأُ فِي بَعْضِ حُجَرِهِ فَيَسْمَعُ قِرَاءَتَهُ مَنْ كَانَ خَارِجًا  

[Machine] The Prophet ﷺ passed by Abu Bakr while he was praying and lowering his voice, and he passed by Umar while he was praying and raising his voice. When they both gathered with the Prophet ﷺ , he said to Abu Bakr, "O Abu Bakr, I passed by you while you were praying and lowering your voice." Abu Bakr said, "I heard the One whom I was conversing with." Then he said, "O Umar, I passed by you while you were praying and raising your voice." Umar said, "O Messenger of Allah, I use it as a means to wake up the drowsy." The Prophet ﷺ said to Abu Bakr, "Raise your voice a little." And he said to Umar, "Lower your voice a little." And this was narrated from the Prophet ﷺ by Thabit al-Bunani, who mentioned it as a hadith mursal (a report where the Successor drops the name of the companion he heard it from, and transmits it as a statement of the Prophet). He said, "O Messenger of Allah, I use it as a means to wake up the drowsy and repel the devil."  

أَنَّ النَّبِيَّ ﷺ مَرَّ بِأَبِي بَكْرٍ وَهُوَ يُصَلِّي يَخْفِضُ مِنْ صَوْتِهِ وَمَرَّ بِعُمَرَ وَهُوَ يُصَلِّي رَافِعًا صَوْتَهُ فَلَمَّا اجْتَمَعَا عِنْدَ النَّبِيِّ ﷺ قَالَ لِأَبِي بَكْرٍ يَا أَبَا بَكْرٍ مَرَرْتُ بِكَ وَأَنْتَ تُصَلِّي تَخْفِضُ مِنْ صَوْتِكَ قَالَ لَقَدْ أَسْمَعْتُ مَنْ نَاجَيْتُ فَقَالَ مَرَرْتُ بِكَ يَا عُمَرُ وَأَنْتَ تَرْفَعُ صَوْتَكَ قَالَ يَا رَسُولَ اللهِ أحْتَسِبُ بِهِ أُوقِظُ الْوَسْنَانَ فَقَالَ لِأَبِي بَكْرٍ ارْفَعْ مِنْ صَوْتِكَ شَيْئًا وَقَالَ لِعُمَرَ اخْفِضْ مِنْ صَوْتِكَ شَيْئًا 4701 وَأَخْبَرَنَا أَبُو عَلِيٍّ الرُّوذْبَارِيُّ أنبأ مُحَمَّدُ بْنُ بَكْرٍ ثنا أَبُو دَاوُدَ ثنا مُوسَى بْنُ إِسْمَاعِيلَ ثنا حَمَّادٌ عَنْ ثَابِتٍ الْبُنَانِيِّ عَنِ النَّبِيِّ ﷺ فَذَكَرَهُ مُرْسَلًا إِلَى قَوْلِهِ قَالَ فَقَالَ يَا رَسُولَ اللهِ أُوقِظُ الْوَسْنَانَ وَأَطْرُدُ الشَّيْطَانَ  

Raise your voice a litte ; or he said to 'Umar: Lower your voice a little. But this version adds: (The Prophet said:) I heard you, Bilal, (reciting) ; you were reciting partly from this surah and partly from that surah. He said: This is all good speech ; Allah has combined one part with the other; The Prophet ﷺ said: All of you were correct. (Using translation from Abū Dāʾūd 1330)   

عَنِ النَّبِيِّ ﷺ بِهَذِهِ الْقِصَّةِ لَمْ يَذْكُرْ فَقَالَ لِأَبِي بَكْرٍ ارْفَعْ شَيْئًا وَلَا لِعُمَرَ اخْفِضْ شَيْئًا قَالَ وَقَدْ سَمِعْتُكَ يَا بِلَالُ وَأَنْتَ تَقْرَأُ مِنْ هَذِهِ السُّورَةِ وَمِنْ هَذِهِ السُّورَةِ قَالَ كَلَامٌ طَيِّبٌ يَجْمَعُهُ اللهُ ﷻ بَعْضُهُ إِلَى بَعْضٍ فَقَالَ النَّبِيُّ ﷺ كُلُّكُمْ قَدْ أَصَابَ