Apparently very few of us ever heard of Charles Ives, let along took note of him. If you're ever looking to change that clue, maybe Stravinsky's first name? Americans are already a little overrepresented in this quiz, and Russians definitely deserve a shout out.
I was surprised not to see Irving Berlin, but I hope Ives is left as is. I'd never heard of him before now, but I looked him up on Wikepedia to learn. I'm still not familiar with his music, but I like the title of the political pamphlet he wrote and distributed, "THE EFFECTS OF TOO MUCH POLITICS IN OUR representative DEMOCRACY". It, like his music, was ignored during his lifetime.
For the "interval" clue, it should read like this, "The distance in pitch between two notes." At first I thought it meant the distance between the notes on the page, not pitch. It makes sense now, but could be a little confusing.
after thinking of instrument I doubted for a few seconds before typing it in. I thought this cant be it, and reread the question again, and thought well.. it does look like this is it... still doubted ... and then, ah well, might as well try it...
haha