In the video linked in the previous post, one of the hosts mentions at one point:

The biggest rebuttal is that the greatest audio engine of all time, the one baked into all Apple products, has 16 volume steps. And no one has ever been like, “My iPhone doesn’t have enough granularity to the volume.”

But of course they have. And the solution is easy: on both the iPhone and Mac you can grab one of the many volume sliders and immediately get a lot more precision:

(Can’t help but notice this volume control has a nice set of notches, too!)

But if I told you that you can actually also increase the precision from 16 to 64 stops using the volume up/down keys, would you know how to do it?

Occam’s Razor: it must be a modifier key. So let’s go through them all.

Pressing ⌥ and brightness up/down opens the Displays settings pane, and consequently, pressing ⌥ and any of the three volume keys gives you the Sound settings pane. (This convention, however, isn’t followed for other keys. ⌥ and Mission Control only opens top level of Settings, and ⌥ and other function keys like Spotlight, Dictation, or media transport doesn’t do anything. My guess is that someone simply forgot about this over time which is a pity, because one of the best ways to teach people about a power-user shortcut is to make it as universally transferrable as possible, to allow motor memory to blossom.)

So ⌥ is out. ⌃ and brightness keys changes the brightness on the external display, and even though that doesn’t really apply to volume, it’s safe to stay away.

⇧ + volume keys reverses the meaning of this toggle below, making ping sounds if the toggle is off, or suppressing them if the toggle is on. This is nice.

That only leaves Fn/Globe which already reverses top-row keys into function keys, and ⌘. But ⌘ is inert. Instead, the combination to add precision is ⌥ + ⇧ + volume keys. (Same with brightness, which can be useful e.g. on a very dark plane.)

I don’t understand this, and I wonder what is the reason it got this way. Modifier keys are generally tricky, but this doesn’t follow any of the go-to rules I would try in this situation:

• Reuse an existing convention for consistency: I don’t think anywhere else ⌥⇧ means “precision.”
• Follow naturally from existing UI building blocks: ⌥ and ⇧ do different things and this is not an intuitive combination of what they do independently.
• Use mnemonics: This doesn’t feel like it’s doing that at all.
• Failing everything else, make it pleasant to press: ⌥ and ⇧ is possibly the least ergonomic two-modifier-key combination.

This shortcut has another problem, which is that it is the only two-modifier-key option here. If you don’t use it often, you might only remember it as “two modifier keys” without further detail, which actually ends up being 10 possible combinations of keys! So if you’re like me, you always awkwardly button mash a bunch of them before rediscovering ⌥⇧.

My recommendation for a small tweak here?

• ⇧ and brightness/​volume: Secondary display/Add pings (both are most important; Shift is nice to press and the “default” modifier key).
• ⌃ and brightness/​volume: Add extra precision (as that gives you more control).
• ⌥ and brightness/​volume/other keys: Open the relevant Settings pane.

Obviously, I might not have all the information that led to the current situation (and it’s possible I don’t even understand it fully), plus changing any long-existing shortcuts is hard. But as above, ⌥⇧ is so peculiar, and it also misses out on the last important consideration: I don’t think anyone would ever discover it by mistake or out of curiosity.