The tar shehnai (“the stringed shehnai”) is an instrument created within the last 200 years.
To amplify the sound of the esraj, musicians applied a sound horn at the base of the instrument. Rather than amplifying its sound, it converted the sound to something that resembles a shehnai. Since there aren’t many people who take up the shehnai as their instrument of choice, they use the tar shehnai if any shehnai pieces are needed.
Apart from the sound horn, it is identical to the esraj in every aspect.