Jascha Heifetz gave the US première of Prokofiev's Violin Concerto No. 2 in 1937 with the Boston Symphony Orchestra under Serge Koussevitzky and three days later made his first successful large scale RCA recording with the same piece and orchestra. He we find them some twelve years later, in a recording of both the Prokofiev and Mozart's Fourth Violin Concerto made surreptitiously at Boston's Symphony Hall using a concealed microphone.
With XR remastering and restoration the resultant sound is remarkably fine, and it gives us a rare opportunity to hear these musicians in concert without the knowledge of microphones being present and the possibility of the music being captured for future listeners - in short, it's the real deal.
The third work here is the Mendelssohn Violin Concerto, in a version derived from two of Heifetz's regular NBC broadcasts in a radio (and later TV) series called The Bell Telephone Hour, largely given over to shorter works. Recorded in live broadcasts from the same studio some two years apart, with the Bell Telephone Orchestra under Donald Voorhees, this is the first time these recordings have been brought together and released as a whole.