The guys at Pigtronix are absolute mad scientists who are never satisfied with creating straight-ahead effects (though they have a few). Take, for instance, the Echolution. It’s unlike any delay pedal on the market. Sure, it does the standard delay types, but also adds the Golden Ratio type as well. If you’re not familiar with the Golden Ratio, you can read about it here. Essentially, the Golden Ratio is expressed as Greek letter Phi, and is approximately 1.6180339887… It is significant because it occurs in nature (the arrangement of eyes on a pineapple follow the ratio, even the arrangement of leaves on a tree), and the ancients also considered objects created using the Golden Ratio were aesthetically pleasing. Also look up the Fibonacci sequence. It’s fascinating, but I digress…
Anyway, the Pigtronix guys have come up with an incredible tremolo box that also includes features associated with an envelope filter; specifically, those features come on depending upon how hard or soft you play. For instance, you can set the Tremvelope to go faster with more depth as you play harder and vice-versa.
I dig stuff like this, and I dig how Pigtronix’ mad scientists think of combining different things to come up with original expressions of tried and true effect. Here are a couple of demo videos courtesy of Andy at Pro Guitar Shop: