Title: Experimental study of large-amplitude standing-wave field obtained in a standing-wave tube with uniform cross section

Author(s): MIN Qi; HE Wanquan; WANG Quanbiao; GE Shuping; WANG Shengyu;

Affiliation(s): Honghe University

Abstract: A large-amplitude standing-wave field of 182.1 dB is obtained under the excitation at the resonant frequency of the lst-order peak of the sound pressure transfer function in an improved standing-wave tube experimental system, and saturation of harmonics and waveform distortion are investigated experimentally for the large-amplitude standing-wave fields obtained under the excitations at the resonant frequencies of the 1st-to the 5th-order peaks. The results show that although the sound pressure level has reached 182.1 dB under the excitation at the resonant frequency of the 1st-order peak, the waveform distortion is the minimum and the harmonic saturation is not observed. However, the large-amplitude standing-wave field excited at the resonant frequency of the 3rd-order peak exhibits the trend of the harmonic saturation. Comparison of the large-amplitude standing-wave fields obtained under the excitations at valley resonant frequencies shows that the standing-wave field excited at the resonant frequency of the 1st-order valley has the largest SPL, but also has the largest waveform distortion. Under the same source-driving voltage, the standing-wave field excited at the resonant frequency of the 1st-order peak always has greater SPL than the standing-wave field excited at the resonant frequency of the 1st-order valley. Hence, to obtain a large-amplitude standing-wave field, it's better to excite at the resonant frequency of the 1st-order peak of the SPTF by using loudspeaker in a standing-wave tube with uniform cross section.