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tokens: spectral line, which is used to derive the information of the magnetic fields. In addition, Qiu Gary ( 2003 ) discussed the possibility of change in line profiles during a transient polarity reversal observed in the photospheric magnetic field measurements obtained from the MDI instrument aboard SOHO space mission. Wang ( 1992 ) and Wang et al. ( 1994 , 2002 ) reported abrupt and permanent changes in the evolution of magnetic fields in the flaring region during the different class of solar flares using the data from Big Bear Solar Observatory. Later on, extensive analysis done by Sudol Harvey ( 2005 ) and Petrie Sudol ( 2010 ) of X- and M-class solar flares using the line-of-sight (i.e. longitudinal) magnetic fields obtained from Global Oscillation Network Group (GONG; Harvey et al. 1996 ) instruments, showed abrupt and permanent changes in the magnetic fields in the flaring locations within 10-min duration with a median magnitude of 100 G. In addition, Kumar et al. ( 2016 ) also found abrupt and persistent changes in line-of-sight magnetic fields at different locations in active region during an M6.5 class solar flare using the data from Helioseismic and Magnetic Imager (HMI; Schou et al. 2012 ) instrument aboard the Solar Dynamics Observatory ( SDO ; Pesnell, Thompson Chamberlin 2012 ) space mission. Hudson et al. ( 2008 ) and Fisher et al. ( 2012 ) proposed that abrupt changes in the magnetic fields can lead to an impulsive change in Lorentz force, which is also known as ‘magnetic-jerk’, and this can induce seismic emission in the sunspots. However, Raja Bayanna et al. ( 2014 ) observed distortions in the two circular polarization states of light, the left (LCP) and the right circular polarization (RCP) observations in the flaring locations which showed transient changes in Doppler velocity and line-of-sight magnetic fields during an X-class flare, using the line profile observations from HMI instrument aboard the SDO space mission. They showed that observed transient changes in Doppler velocity and line-of-sight magnetic fields in flaring locations are prone to artefacts in the measurements. Therefore, in this paper, we present a detailed analysis of seismic emission in the sunspots, which are away from the flare ribbons and hard X-ray footpoints accompanying large solar flares. Such acoustic enhancements are supposed to be free from any flare related problems in the observational data. In the following sections, we first describe the observational data and selection criteria for choosing the active regions aimed for our analysis. This is followed by methods of analysis and the results obtained. We finally conclude with discussions concerning our results. 2 THE OBSERVATIONAL DATA We have extensively used observations from the HMI instrument aboard the SDO spacecraft, which is a solar space mission of the National Aeronautics and Space Administration (NASA). The HMI instrument observes the photosphere of the Sun in Fe i 6173 Å absorption