"Allah and His angels say salah upon the front rows, and the Mu'adhdhin will be forgiven as far as his voice reaches, and whatever hears him, wet or dry, will confirm what he says, and he will have a reward like that of those who pray with him." (Using translation from Nasāʾī 646)
أَنَّ نَبِيَّ اللهِ ﷺ قَالَ إِنَّ اللهَ وَمَلَائِكَتَهُ يُصَلُّونَ عَلَى الصَّفِّ الْمُقَدَّمِ وَالْمُؤَذِّنُ يُغْفَرُ لَهُ مَدَّ صَوْتِهِ وَيُصَدِّقُهُ مَنْ سَمِعَهُ مِنْ رَطْبٍ وَيَابِسٍ وَلَهُ مِثْلُ أَجْرِ مَنْ صَلَّى مَعَهُ