112dB Redline Reverb by scadh
112db's Redline Reverb is one of several interesting, high-quality plugins in the Redline family. It sounds incredibly natural with nary a trace of the "metallic, tinny" tails prevalent in some software reverbs.
The "tweakability" factor is to the extreme and makes it possible (note that I didn't say *easy*) to sculpt a a reverb that sounds like virtually any space. There is no option to select a particular "starting point" space, such as Hall, Plate, etc. Instead, such signature styles are dialed in by hand. Individual frequency setting for early and late reflections, separate treble/bass response, hi/lo damping and extremely long decay times make it fun to just twist knobs and see what it gets you. This plug is capable of very subtle, unobtrusive depth for spoken word uses one minute, and extremely rich, ethereal ambiance the next.
The GUI is clean and straightforward, and offers one-click access to 8 user-definable "favorites". Most of the presets are terrific straight out of the box, though a few are more of the "look at what *I* can do" variety rather than something you're likely to use frequently. Still, there are plenty of presets that make great starting points for any style of reverb you could want.
It is completely algorithmic rather than convolution-based, so it offers a very light cpu/memory footprint. I frequently use an instance of it on 3 different busses -- vox, drums and guitar/bass -- and have never noticed any slowdown or severe latency attributable to it.
All in all, Redline Reverb is a great value. Not exactly "cheap" at $150, but also not $500+ like Altiverb. I have never tried Altiverb, but can't imagine that any improvement it might get you in sound wouldn't be more than made up for by Redline being less than 1/3 the price. Highly recommended. There's a free demo available from 112dB.