Here's what they say:
Released in June 2011, The original Lorelei suite comprised of three applications designed to reduce the time it took to generate new musical ideas and audio material. After receiving awards from Computer Music Magazine, and a favourable review from Sound on Sound, the developer worked in stages to create the new versions of the original Generative and Feedback applications. The new applications retain the same core ideas of generating drone and loop based audio material via delays and granular synthesis, but give much more control to the user over how the sound is created.
Generative 2 (£30)
The Generative application has received the biggest overhaul, with a number of new features that make it a significant tool for generating evolving soundscapes and drones. Perhaps the biggest change is the ability to save and restore sessions, allowing the user to create complex sounds and restore them. The four granular players can now have independent pitch and filter settings, and a new 'states' dialog allows the user to save up to sixteen states within a preset that can be switched between.
Feedback 2 (£25)
Feedback has had many refinements internally to save CPU usage, and features new audio file playback modes which allow users more creative freedom when manipulating audio files. The delay times can now be controlled via MIDI, as well as the input and output effects, which further enhances Feedback's capabilities in as a live performance tool. Also included with this update are improved filters and a new reverb effect.
Both applications are available on Mac and Windows, and can be purchased through the newly designed Siren Audio website.