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Boring is a process which the diameter of the internal hole of the workpiece usually increases from the initial size to the desired value in some stages. In this operation, undesired vibrations lead to decrease in the smoothness of the surface; thus, active dynamic absorbers have been used to dampen the vibrations. In this research, two analog and digital accelerometers are used with an active dynamic absorber installed on a 720 mm boring bar. The analog sensor is used as a validation of the economical digital accelerometer. Therefore, thanks to the velocity feedback method, the vibrations caused by any impact forces have been damped and compared with the state without the presence of an active dynamic absorber. Furthermore, in this research, by increasing the amount of input voltage to the amplifier, the damped results of the impact applied to the end of the cutting tool have been increased remarkably and the frequency spectrums have been presented and examined to predict the damping.