[mjgoeke]

I can’t speak for the entire spectrum available. But I have two data points and am shocked at the difference, since I expect none. At home I have a rancilio rocky grinder, bought used, newly replaced burrs. It’s “stepped” so I don’t have much fine tuned flexibility - I’m basically choosing between only two or three steps for espresso.

My friend has a Pharos manual grinder. I’ve come over to help his wife adjust the grind several times. I bring the same beans I’ve been using that week as a reference point. I’m always shocked how much better theirs tastes - even far-out-of-optimal shots - ones that are very fast or very slow. On my machine the unpleasant overextracted flavors creep in quickly. I chalk it up to consistency of the grind - and that’s observable. You can pinch grinds up and “smear” them across a white sheet of paper to observe size, and to a lesser extent, variability.

I’m still surprised that the grinder affects the espresso more than the espresso machine.

Note: the Pharos is a beast and I don’t recommend it unless you like armwrestling as part of you coffee prep every time.