Mishkat al-Masabih 4 Prayer كتاب الصلاة 173

وَعَن مَالك قَالَ: بَنَى عُمَرُ رَحَبَةً فِي نَاحِيَةِ الْمَسْجِدِ تُسَمَّى الْبُطَيْحَاءَ وَقَالَ مَنْ كَانَ يُرِيدُ أَنَّ يَلْغَطَ أَوْ يُنْشِدَ شِعْرًا أَوْ يَرْفَعَ صَوْتَهُ فَلْيَخْرُجْ إِلَى هَذِهِ الرَّحَبَةِ. رَوَاهُ فِي الْمُوَطَّأِ

Malik said that ‘Umar built a courtyard called al-Butaiha’ in the neighbourhood of the mosque and said, “If anyone wants to make a noise, or recite poetry, or raise his voice, he must go out to this courtyard.” He transmitted it in al-Muwatta’ .