What is Gen 2?

[BudP]

Gen 2 EnABL is just a different application of the same simple formulaic response, just a pattern of paint blocks. The gen 2 thing is all about where to place the paint. Specifically, at the point where the transverse wave is causing a high energy emission to occur, one that is forcing the direct pressure waves created by pistonic motion to deform and ring, in a torus loop, off of the cone or dome or planar or horn or baffle surface. Can't happen there?. Please look at the 4 youtube videos on resonance pointed to in the list of sites. These locations for placement are apparently what the usual Cymatic resonance domes form from and disturbing the location they arise from appears to mitigate their effects. Or, something completely magical is occurring. I vote for magic personally.

Whatever is being interrupted does appear to create those "breakup" mode sounds we all refer to when using drivers above their pistonic frequency region. Oddly, these breakup modes are not related to the jagged frequency response that occurs in the non pistonic realm, except as diminished peak energy emissions. Application of EnABL and a nice waterfall plot show this clearly. Also, application of the "extra" rings, out past the minimum phase portion of a cone, the inner part that actually has minimum phase performance, raises the high frequency phase tilt, with the outer ring controlling the highest frequencies.

There are three "sectors " to a tap.

Initial strike. This is what most people hear as a tap. We are geared to pay attention to initial arrival of any sound. You can use this portion of the tap sound to locate Raleigh waves and that is all. As you tap in a radial line there will be a sector that responds noticeably more vigorous than adjacent areas. This is very likely to be a Raleigh wave, but you cannot be certain until the rest of the driver is under control. Usually you must apply a damping material, in a fairly narrow band, on the other side of the diaphragm right under this area.

Mid tone. This is useful for finding subduction zones, usually immediately adjacent to Raleigh wave zones. This zone sounds dead compared to zones before and after, no tone to speak of. A pattern set in the middle of this zone and one just as it begins are the solution. Typically one pattern set at the point where the tone goes dead is sufficient and all that will fit. In 10 inch and larger cone drivers you may end up with more patterns here.

Decay tone. Here is where you will find most of the places to apply patterns. In listening to the decay you will have to ignore the other components from this tap. As you listen to the tap decay, while taping radially along the surface, you will notice a narrow zone where the decay seems to loose direction and then change direction as you move back and forth across it. Once you can focus on just the decay portion of the tap this will become fairly obvious. A pattern set in the middle of the directionless portion will disperse this activity completely.

The end product you are looking to achieve is a smooth change in direction of decay tone. From straight out or even slightly toward the center of the voice coil, when taping next to it, to aimed off the cone, parallel to the cone angle, out at the outer edge of the diaphragm. Dome diaphragms are a bit different but you will still find the same directional switch as you tap up the side of the dome. Same rule applies for placement and the eventual decay pattern will shift from lateral at the beginning of the dome to straight out on axis at the tip. In all cases the surface of the driver will seem to be "faster" than another untreated driver of the same part number. The tap will be dispersed very quickly with no echoes.