It's a slimmed down (2.5 GB) version of the full library yet to be released. Mic positions, true legato, and several articulations have been cut, to center the "Micro" version around straightforward spiccato, staccato, pizz, sustains (with scripted legato), and some nice cres/decresc oneshots.
I'm really digging these strings as a layering tool. Even the mixed-mic sound in HyperionMicro is more present and dry than the close mic option in other libraries. It's a little drier than the close mic in CSS, about equal to Adventure Strings, and much more present and dry than the close mics in Mural and Fluid Shorts. So this is one more tool to add presence to strings without having to reach for the EQ.
I think the staccatos and spiccatos are well executed. They can't really be combined in a phrase, as the staccato is quite long, but the manual says the full version will include "additional staccato and spiccato types" so I expect there's a short staccato &/or staccatissimo to bridge the gap.
The crescendo and decrescendo one-shots have real power behind them and are lots of fun.
The pizzicatos are good and even have a "performance scripting" feature that automatically tightens up the samples when you play a series of fast plucks in a row.
The weakest aspect of the Micro version of the library is the sustains, as there's only simulated-legato (full version will have real legato according to the manual). There's nothing to write home about in the scripted legato, it sounds like EWQLSO. I recommend turning the "Response" slider all the way up to make the best of it.
The library seems to have 3 dynamic layers for all articulations, from what I can tell. The top end hasn't been neglected though - there are some really ballsy forte and fortissimo samples in this library. The sacrifice comes in not having true pianissimo samples, and a slight awkwardness bridging from piano to mezzo-forte. But that's compared to libraries that cost hundreds of dollars!
The UI is really good. It reminds me of the recent discussions of UI redo's by Spitfire (HZS/Labs) and 8dio (their old orchestral lines). Here, SoundIron have just got it right.
There's a lot of on-board doodads like an EQ, a compressor, various reverbs (including some very spacey ones), an arpeggiator, and even one of those lock-all-keys-to-a-specified-scale thingies. Pro composers probably won't use any of this, but it works with the library's entry-level appeal.
There seem to be an increasing number of libraries that are not trying to be symphonic in scope or traditional/classical in sound-character, as that would bring them in direct competition with flagship libraries like Mural, LASS and Hollywood Strings. When you count up the features like: a merged violin section, 23-player ensemble, forte-oriented dynamics, production-music sound, etc... Hyperion seems to be playing in almost the exact same market as AudioImperia JAEGER, including the announcement that brass and woodwinds are on the way. Other close comparisons could include the Performance Samples lineup with its innovative new sampling tech, and Light & Sound Chamber Strings with its close perspective. It'll be interesting to compare the full version of Hyperion to those libraries.