hi there. i wasn’t sure if this was normal, but when art is at the top of the cutting area the movement of the laser sounds really low and deep, and if the art is toward the bottom of the cutting area, the sound is high pitched (what i’m used to). is this normal?
here’s a video
Yes, that sounds perfectly normal. Side to side movement only engages one stepper motor, forward and back movement engages two, and angular movement engages all three. So they have a significantly different sound.
(I fancy the machine is singing, and after a while you can tell what’s happening in the file just by listening to it.) 
Love it! (I can’t imagine the work that needed to go into coding something like that!) 
Some days mine sings to me more than others… so far no sand raiders howling at me, though (keeping in mind the impressive programming the fellow did for his 3-D printer!
I so do that with Glowforge, 3-D printer, and X-carve and I never really thought about it too much. Circles, curves, vertical moves, horizontal moves, in-fill and external walls (3d printer), engraves, switching parts, ………
It’s too bad that you wouldn’t be able to hear flare-up and fire before it’s too late.
Crackling and popping? 
thanks for your feedback, everyone! we did a complete cleaning of the air assist and took the belt off. i was paranoid that the noises were changing and i did something funny. these videos are hilarious!
Thanks @jules, that’s it exactly.
@edyvetter, from the video you shared, everything sounds like we would expect for the direction and speed the laser head was moving during the video.
I’m going to go ahead and close this thread but if you have any other questions please don’t hesitate to open a new thread or email support@glowforge.com