We utilized an audio digitizer in energy‐dispersive X‐ray fluorescence (EDXRF) with a silicon drift detector and achieved a full width at half maximum (FWHM) of 178 eV at Mn Kα (92‐µs peaking time). To confirm the ability of EDXRF with an audio digitizer, we also examined energy versus channel number linearity and output count rate. We applied it to EDXRF analysis of (ZnCd)S : Ag and showed a proper energy versus channel number linearity from 5.9 keV (Mn Kα) to 26.1 keV (Cd Kβ). And, the maximum output count rate of more than 10 kcps was obtained with 23‐µs peaking time (296‐eV FWHM). Copyright © 2011 John Wiley & Sons, Ltd.