Water is most of the coffee

A cup of coffee is almost entirely water, which means your water is almost entirely the coffee. People spend on beans and a machine, then brew with whatever comes out of the tap, and wonder why the version at the bar tastes better.

You do not want distilled water, which is flat and lifeless and pulls nothing out of the grounds. You do not want hard water full of scale, which is what put the machine before Beatrice in an early grave. You want filtered water with a little mineral left in it, enough to give the coffee something to hold onto.

If your tap water tastes like a swimming pool, your coffee will too, politely. Filter it. That is most of the gap between your kitchen and our bar, more than the beans, more than the machine, more than anything I could teach you about the pour.