Ibn Ezra on Psalms

And the word "laanot"-- is like the phrase "qol anot" (Ex. 32:18). Said Yeshua b. Yehuda: "This is Heman the son of Samuel and the Bible calls him Ezrahi because he was a native of the bards, for most bards were his children and grandchildren as it is written in Chronicles." And some say that the aleph is prosthetic and he was the son of Zerah and his brother was Ethan. And others say that Heman and Ethan were brothers whose father was called Ezrah.