As I prepare to take a step up in machine, I have been reading about brew pressure. This is a pretty old thread. I'm surprised this subject isn't more topical as machines are improving. One concern I've had is how I will most likely lose the control over pressure that I now have with the La Pavoni lever, even with a machine like a Synesso. Almost instinctively, I pull on that lever with varying degrees of force depending on the grind, and how the pour looks.
All of this talk about pressure control is addressed by pulling on a lever. But to accomplish this with an armature might require going to three phase with a converter, and varying the pump speed. Transducers in the lines. One example of this is the fairly new "constant pressure" well pump system. It elminates the pressure tank, and provides a continuous feed of water at pressure, regardless of usage.
As for smoothing out the bumps, an accumulator tank would probably act like a capacitor.
The only problem I see with adding another parameter to the brewing process is that it would add another dimension to an already difficult situation. But I can just envision an espresso machine that has a mouse operated interface whereby one can drag the pressure and temperature profiles around. I'm not sure we'd ever have time to actually drink coffee though.
Discuss flavors, brew temperatures, blending, and cupping notes.