Lever machines with a Pavoni focus
The La Pavoni is a manual lever machine, which is one of the common machines that people buy when they decide to make a foray into expensive espresso machines. New they run at least six hundred dollars and some of them run quite a bit more.
Lever machines do not (usually) have pumps and the user provides the pressure that pushes the water through the coffee instead of an electric pump. They are usually broken down into two categories. The first is manual levers where the lever is raised and the pressure used to lower is the pressure exerted on the coffee. The barista can vary his or her pressure as the shot proceeds, a neat trick that even far more expensive machines cannot do (although some very, very expensive machines are now being designed with pressure profiling so that the barista can program in a change in pressure in advance to imitate the lever. The only problem is these are all many thousands of dollars and are mostly only used in high end coffee shops not at home).
The other category is the spring lever. Spring levers are as you would guess powered by a spring. The barista cocks the lever and then releases and at that point the spring powers the water through the coffee. Many people love the flavor of these machines and they are a little easier to use than the manual levers and this is one of the frequent targets in pressure profiling machines where they try to program the profile to have a pump imitate a spring. One of the most popular versions of these machines is the Elektra. It is also one of the prettiest machines on the market.
My main experience is with manual levers and so this is what I will write about as opposed to spring levers.
If you see a lever machine and do not know if it is a manual or a spring a key can be to look at the lever at rest when not in use. Spring levers are naturally at rest with the lever pointing up and manual levers have the lever point down.
edit to add: Hmm, they were supposed to be linked below, but when I posted it they didn't show up and coffee did intead, so here is a link to the machines in case that issue never fixes itself.