what kind of bug

just visited Toronto and the trees were full of a high pitched noise that moved through from tree to tree - didn't see any bird or bug but assume it was a bug - anyone know what it is

the same sounds were at Niagra falls

cicadas, I'd bet.

looked up the sound of these and i think the ones i heard were a higher pitch - almost electrical sounding

Sounds like Cicadas to me. Here are some pics:
https://photography-on-the.net …hp?p=10654589&p​ostcount=1

They can vary greatly in color, though. I've seen pale green to almost black here.

Believe me, they can be very high-pitched & sometimes so loud that you can't carry on a conversation with the person right next to you. When they are "in season" (where I live that would be Jan/Feb) it - the noise, that is - sometimes goes from sunrise to sundown; and when the last little bugger stops the silence feels wonderful. If you are in an area with active cicadas & it appears to only be "raining" under certain trees, don't stand under them & gaze up!