On a side note, I noticed that Eventide has a VST for space - think I'll check that out.
No doubt that you've discovered it's the single Blackhole algorithm from Space. It's a cool, out-there 'verb configuration, but it won't have the pitch shifting capabilities of the
Shimmer algo. Unless I'm really missing something here.
I am not a U2 fan, and as such have no idea what this effect is, but I'm curious.
You've probably heard it before, Bit. It's like a synth wash echoing the input in upper octaves. The "ADSR" can be volume pedal, playing technique, eBow ... followed by cavernous reverb and/or delays for the sustain & release. Compression can help. I've also used an EHX Freeze or Pigtronix Philosopher King for the envelope.
An essential part is the pitch shift - one or two octaves up. Some add chorusing; I prefer slight detuning at the octaves. Parallel routing is optional. One of the early Lanois applications used recirculation of the octaves in the delay line. It's something I use often for a cascading 'barberpole' effect. You run out of upper bandwidth after 2-3 iterations anyway, but it adds to the initial buildup. Of course, stereo enhances the sense of space.
Not a huge U2 follower, either, but people often point to the
47th Grammy performance video to illustrate the shimmer effect. I'd rather give props to Bill Ruppert and what he does with EHX effects in the Effectology series. The
first part of this video shows shimmer effects & some variations. In the second part he goes symphonic with a favorite of mine, Adagio for Strings.
I'm not convinced about the Y-Adapter application, though.