Abstract: In this paper,we present a simpler method to calculate the distribution of the pistonlike sound fields,which extends the approach proposed by Wen and Breazeale.The distribution function on the source is expressed as the product of one function and a Gaussian sum of the step function,and the calculation of the sound fields reduces the estimation of sums of some relatively simple functions such as the M-shape and Gaussian ones.Some of pistonlike fields are evaluated,and the results indicate that this approach is very successful.