What is the difference between a Maihar sarod and a conventional sarod?

The Maihar sarod is a larger design with 25 strings, usually tuned to C. The conventional sarod carries 17 to 25 strings and is usually tuned to B. A third design, from the school of Radhika Mohan Maitra, may carry a second resonator. All three keep the goatskin belly and the smooth metal fingerboard.