Original by MJR – ref : http://www.vpforums.org/index.php?showtopic=30971&p=305386
Release Speed now controls the analog plunger release strength. When a release motion is detected from the mech device, the simulation plunger fires with the Release Speed setting.
Mech Strength is still used, but it’s less important than it used to be because of the way Release Speed takes over when a release motion occurs. Mech Strength still determines the coupling strength between the mech plunger and the simulation plunger, so it will still control the speed imparted to the ball when you move the mech plunger slowly (slower than the release threshold). Setting this to about the same value as Release Speed seems to work well for me.
Pull Speed sets the rate of pulling back the plunger via the keyboard interface (usually pressing and holding the Enter key). This has no effect on the mech plunger motion.
Stroke Length sets the on-screen length of the plunger, so it applies to all interfaces.
Scatter Velocity is a randomness factor added into the launch speed. This applies to all interfaces. If you’re using a mech plunger, I’d set this to zero. Its purpose is to simulate the mechanical randomness in a physical plunger, so if you’re actually using a physical plunger, you don’t really need both simulated and real mechanical randomness.
I’m not sure why Mech Plunger Adjust was created in the first place; it’s basically a scaling factor multiplied into the plunger force calculations, so you can get the same effect by adjusting the other strength parameters. It’s applied globally, so maybe someone thought it would be handy to have a way to tweak both plungers in Funhouse at the same time with a single parameter.
As for Filter Mechanical Plunger, that’s another one I’m not sure about. I’ve never enabled it. In terms of what it does, it applies a low-pass filter to the raw mech plunger input data, which is to say that it smooths out rapid changes from the data. My guess is that it’s very specifically designed for a particular commercial plunger kit, probably one of the early ones like the Nanotech kit. I say this because the filter has particular parameters that must have been chosen empirically to improve results with some specific testing hardware. The Nanotech kit uses an IR proximity sensor, and those are pretty jittery, so that would fit with this explanation.