Ud Amir Khan was one of the greatest musicians of the last century. Although very well known to regulars of Indian classical music, he remains relatively unknown among the population generally.
He inspired many stalwarts including Ud Vilayat Khan, Pt Nikhil Banerjee and others. I personally consider his Darbari as the mother of all renditions of North Indian Classical Music of this raga – maybe only Tansen could have surpassed him.
Here is a collection of some articles on this “musician of musicians”.