The Analysis of Room Acoustic Parameters of Karaoke Rooms in Surabaya

This research is performed to evaluate the acoustic parameter and noise of several karaoke rooms in Surabaya. The type of rooms can be classified into small rooms and large rooms. All the measurements were conducted at 12:00 to 16:00 GMT+7:00. Based on the measurement results, noise criteria (NC) values range between 45 and 50. These values are quite high if compared to standard NC value, i.e., 25. This statement is in accordance with the low values of noise reduction (NR) of evaluated rooms: walls with glass accessories (12 - 16.5 dBA); door gap (8 - 13.9 dBA); wall (10 - 18 dBA); and door hinge (6.9 - 9 dBA) in the frequency of 1000 Hz. Therefore, the low values of NR lead to NC value exceeds the recommended value. According to the observation and the analysis, we obtain there are some rooms using special doors that are very well to absorb noise. However, those doors still have a drawback because they are equipped with glass which has a low value of NR. The addition of glass to the doors reduces NR value. Moreover, the ranges of reverberation time of small rooms and large rooms are 0.3 - 0.4 s and 0.6 - 0.7 s, respectively. This difference range is caused by the volume of rooms. In addition, the speakers of all rooms are the same, i.e., woofer speakers. It could be understood from the sound spectrum that has a range of 100 - 500 Hz. Lastly, all the analyzed rooms have a high value of noise. The measurement results 94 d B A of L eq and 104.3 d B A of L max . Regarding the health regulation, the sound that has those intensities is harmful to the human hearing.