Notification sound effects

Two warm notes rising with no sharp attack. Built to survive being heard forty times a day, which is the hardest thing to ask of an interface sound.

Three clear bell-like notes. Brighter and more insistent, so it suits something the user genuinely needs to look at rather than routine traffic.

Two flat notes falling. Falling pitch reads as failure without any words, and the dullness is what stops it sounding like a success cue.

A light rounded pop with an instant stop. Almost no information in it, which is exactly right for something arriving constantly in the background.

A hard repeating buzz with no musicality. It reads as a demand rather than a message, so reserve it for things that genuinely cannot wait.

A short rising swell rather than a discrete note. It suits a state change, where a chime would read as a message arriving instead.