AbstrakPenelitian ini bertujuan untuk mengetahui perbedaan morfologi tanaman perlakuan dengantanaman kontrol dan pengaruh intensitas bunyi yang tepat untuk pemaparan suara belalang “kecek”trmanipulasi pada peak frequency 3000 Hz. Obyek penelitian ini adalah 25 tanaman jati perlakuandan 25 tanaman jati kontrol. Suara belalang “kecek” dipaparkan setiap hari pada pukul 06.00 – 07.00WIB dan 16.00 – 17.00 WIB. Pengukuran tanaman jati meliputi tinggi batang, diameter batang,panjang daun, lebar daun, dan jumlah daun. Hasil dianalisis menggunakan Microsoft Excel. Datafrekuensi dan amplitudo suara belalang “kecek” dianalisis menggunakan program Spectra Plus. Hasilpenelitian menunjukkan bahwa suara belalang “kecek” (Orthoptera) termanipulasi pada peakfrequency 3000 Hz berpengaruh terhadap pertumbuhan tanaman jati terutama panjang daun, lebardaun, dan jumlah daun. Amplitudo suara yang tepat untuk tanaman jati yang diberi pemaparan suarabelalang “kecek” termanipulasi pada peak frequency 3000 Hz yaitu (-49,75±0,20) dB yang setaradengan (62,1±0,9 – 69±2) dB.Kata kunci : suara belalang “kecek” (Orthoptera), peak frequency 3000 Hz, pertumbuhan tanamanjati (Tectona grandis, L.f).AbstractThis research was purposed to know the difference morphology the treatment trees with thecontrol trees and the influence of the intensity of the accuracy sound to the grasshopper’s soundexposure which was manipulated on peak frequency 3000 Hz. The object of this research were 25treatment trees and 25 control ones. The sound of grasshopper was set daily from 06.00 am to 07.00am and 04.00 pm to 05.00 pm. The measuring of the trees included the height, and diameter of thetrunk, the length, the width and the amount of the leaves. The results are then analysed usingMicrosoft Excel. Data on the frequency and amplitude of the grasshopper sound analyzed usingprogram Spectra Plus. The results of the research indicated that the grasshopper’s sound exposuremanipulated at peak frequency 3000 Hz influence the growth of teak trees especially the length, thewidth and number of leaves. The accuracy of sound amplitudo which was appropriate for the teaktrees on peak frequency 3000 Hz was (-49.75 ± 0.20) dB which was equal to (62.1 ± 0.9 – 69 ± 2) dB.Keyword: sound of grasshopper, peak frequency 3000 Hz, the growth of teak trees (Tectona grandis,L.f).