Natyashastra
परिघट्टनया तुष्टा युक्तायां राक्षसां गणाः । सङ्घोटनक्रियायां च तुष्यन्त्यपि च गुह्यकाः ॥ ४६॥
"By the action of the percussive sound, the groups of demons are pleased. They are also pleased during the collective activity and by the secret practices."
english translation
parighaTTanayA tuSTA yuktAyAM rAkSasAM gaNAH । saGghoTanakriyAyAM ca tuSyantyapi ca guhyakAH ॥ 46॥
hk transliteration by Sanscript