Hear the idle ~1,300 RPM Mac Studio M1 Ultra fan noise by playing this video at maximum volume (both YouTube volume and iPhone volume) on your iPhone 13 Pro. Then, place your phone where you plan to put the Mac Studio with the iPhone speakers facing towards the back.
While this isn't a 100% perfect match, it is very close. I recorded this fan noise at ~1,300 RPM on a Mac Studio Ultra, and I used a SPL meter to measure the sound levels at various distances. To my ears, this is an accurate reflection of what I hear in my quiet office (for what it's worth, I haven't noticed the sound of the fan, and it's sitting a few feet away on my desk).
Note that I've only tested this at maximum volume on an iPhone 13 Pro, and assuming all iPhone 13 Pros behave similarly, it should be a reasonable simulation. Also note that this is using the fan assembly in the Ultra, which we know to be different than the Max. I don't have a Max to compare it to, so I can't say if they're the same.
