What did Moshe mean when he retorted " ... Kol Anos Anochi Shome'a"?
Rashi: He was saying that what he heard was the sound of blasphemy - that torments the one who hears it. 1
Ramban: He meant that he heard the voice of reveling.
Hadar Zekenim: He meant 'the voice of singing'. 2
Yerushalmi Ta'anis, 4:5 #1: He meant that it was the sound of praise of Avodas Kochavim. 3
Yerushalmi Ta'anis, 4:5 #2: He was intimating that a man who is destned to be a leader over six hundred thousand people ought to know how to distinguih between one sound and another.
And not the sounds of the victor shouting 'Victory!' and the vanquished crying out 'Oy' or 'Run!'
Like "Kerem Chemer Anu lah" in Yeshayah 27:2).
Oznayim la'Torah, citing the Yalkut, commenting on the Pasuk in Eichah, 1:3 "Galsah Yehudah me'Oni", explains that they went inro exile because they served Avodah Zarah.
How did Moshe know what the sounds denoted?
Ramban: Moshe was a master Chacham, who knew how to distinguish between different sounds. 1
Why did Moshe not tell Yehoshua about the Eigel?