There was a similar web-game back in the day but for tones. You had to identify which one was higher or lower. Also gave a statistical comparison at the end. Ne

There was a similar web-game back in the day but for tones. You had to identify which one was higher or lower. Also gave a statistical comparison at the end. Near the end the difference was a couple hertz or something, so next to impossible as well. I can't find it now. Is anyone else aware of what I'm talking about?