A standing-wave tube consisting of two tubes with abrupt changing diameters is dissonant, that is, its higher resonance frequencies are not integral multiples of the fundamental one. Using the dissonant property of the said standing-wave tube, the harmonics can be well suppressed and extremely pure nonlinear standing wave can be obtained at the first resonance frequency. Based on the study of the dissonant property of this standing-wave tube and by the straight connection of a high-power loudspeaker, 184 dB extremely pure nonlinear standing-wave field was obtained at the first resonance frequency. Moreover, the nonlinear standing-wave fields were experimentally investigated separately for the second resonance frequency up to the fifth. Relatively regular nonlinear standing-wave field of 180 dB was obtained at the third resonance frequency, and that of 166 dB was obtained at the fourth resonance frequency. The harmonics saturation phenomena and zigzag waveforms were observed at the third and the fifth resonance frequency, respectively.