Natyashastra
गम्भीरस्वरता येन कुतपस्य भविष्यति । भित्तिकर्मविधिं कृत्वा भित्तिलेपं प्रदापयेत् ॥ ८२॥
The stage should be constructed in such a way that it does not produce a hollow sound, leading to improper acoustics. After completing the wall construction, the walls should be coated properly to ensure proper sound quality.
english translation
gambhIrasvaratA yena kutapasya bhaviSyati । bhittikarmavidhiM kRtvA bhittilepaM pradApayet ॥ 82॥
hk transliteration by Sanscript