I have had a pair of Decapo's since december 2001 and last week I installed the i mod tweeters. The upgrade costs $170 for a pair of new Seas tweeters and it's xovers. The tweeters seem to be an expensive model and physically they look of much better quality than the old ones. They supposedly have much lower resonance and xover frequencies than the older ones. The Xovers consist of a pair of ugly looking multifoil oil caps, painted kind of military green, kind of stealthy looking, so not to make any impression on the sound, I guess, and one resistor. The original xover did not have a resistor btw. It must be for some kind of equalization or impedance purpose. One thing that struck me is that these speakers use one cap for ea. leg, positive and negative-don't know why. The mod is simple to do. The caps are rather large metal cubes approximately 2" ea. side, so to get them inside is a little bit cumbersome. They come connected to the resistor and to the wiring harness, (Van Den Hul wire) Once you remove the old tweeters and xover you have to solder the tweeter and the terminal board to the wires.
The tweeter fits right in. You need to have a Decapo version that has 4 bolts in the tweeter flange for the tweeter to fit.
Now for the good part, sound: The speaker is transformed. It is not a subtle change. Maybe the old tweeters were damaged but the speakers are now in another league. Even the midrange seems to be improved. Details and cues that were buried in the mix before now come out very clearly. One can even hear these over louder passages. I guess that midrange improvement can be explained by the lower xover and resonance frequencies. Tash says that it will even get better, (and it is, by the day) at the 200 hr. mark when the tweeters are fully broken in.
Also, the sound is much more smoother, natural and refined than before. Go for it!
