Tail pipe is a most common structure in mufflers to silence low frequency noise from an engine for its
acoustic performance of low-pass filter. Based on the typical structure, a muffler with an interconnecting
hole on the tail pipe was proposed to improve its acoustic performance in the present research. Acoustic
performances of the proposed muffler were studied experimentally and theoretically in frequency and
time domain. It was found that the interconnecting hole enabled the proposed muffler to have a noise
attenuation performance of Helmholtz resonator. So the proposed muffler can attenuate the noise of
low frequency and middle frequency at the same time. The frequency equation of this structure was
derived using the acoustic-electronic analogy. It is useful for estimating the attenuation performance
at the stages of predesign or tuning. The influence of structure parameters of the proposed muffler on
its acoustic performance was studied. According to the results, the design guideline of this muffler was
concluded in the present research.