An early variant technique, called a balance siphon, was to have the two chambers arranged side-by-side on a sort of scale-like device, with a counterweight attached opposite the initial (or heating) chamber. Once the near-boiling water was forced from the heating chamber into the brewing one, the counterweight was activated, causing a spring-loaded snuffer to come down over the flame, thus turning "off" the heat, and allowing the cooled water to return to the original chamber. In this way, a sort of primitive 'automatic' brewing method was achieved.
“This is simply an amazing machine. I have had NO trouble with it whatsoever. … The quality of the espresso is better than what I get out of the coffee shops — using their beans. It took me a long time to tune in the perfect cup of espresso/latte/cappuccino, and there are variables, but mostly in the beans you buy. I had to buy a decent burr grinder, but considering the investment in the machine, another $150 for a good burr grinder is nothing. I only run filtered water through the machine. I love this machine. I have poured over 2,500 shots through it. Not a single problem with the machine. Many mistakes by the operator, but I will take my espresso out of this machine before any store bought cup-o-Joe.”
“Small things CAN bring you joy. My recent purchase of this Zojirushi coffee maker has made me very happy. Sounds like a commercial, but consider this … Last year, I bought a more expensive coffee maker that made terrible coffee! Instead of using the machine, I started making pour-overs. Something I hate to do … A year and a bunch of customer reviews later, I ordered this new baby, and I am so happy, I am writing about it here. I don’t know if it’s the water filter that water passes through or the fact that the water is introduced to the coffee a little bit differently, but the result is what I consider a perfect cup of coffee.”
Above all, good espresso requires precision. If you’re looking for phenomenal tasting notes, flavor balance, and texture, there is simply no room for error in the machine, the beans, the user, or even the weather. And even if you’re not holding out for the best coffee on the planet, the margin for error is still slim. To test the machines, we pulled shots following the Italian Espresso National Institute's measurement guidelines and paid attention to the following markers of success:
Whole bean coffee that you grind yourself is preferable to pre-ground, too. The bean’s exterior traps and protects all of the delicate, volatile, and water-soluble oils that give coffee its flavor. As soon as you break the protective shell, it’s easy for the flavor to get contaminated, and much of the aroma escapes as soon as the oils are exposed to air.