Next facelift for my Rancilio Audrey will be a pre-infusion mod. There are two ways to do that. Simplest way is to add a couple of water hammer aresters (kudos to JeepinGeo @ coffeegeek.com).
JeepinGeo also posted a Youtube video of this setup (I assume it is the same guy and the same setup) in action.
The second way is to add a programmable timer to the pump electrical circuit. It is a bit more difficult because it requires a relay, power source, wiring, etc. It sounds funny too. On the flip side, it is still simpler than this one:
