IGS Audio ONE LA 500-Series Tube Opto Compressor Used  From IGS

The IGS One-LA fills a gap in that market we've been clamoring for since the emergence of the 500 series format. With a tube device, the problem has always been a lack of sufficient power to the plate. This lack of power results in a starved tube sound that would never work if trying to achieve the true lush and creamy LA-2A sound. By utilizing a double-wide chassis and two separate connection cards that each pull power from the two rack channels, the One-LA solves this problem and delivers the elegant and effortless performance you would expect from a 19" rack processor!

This is not an aggressive, grabby or gritty compressor. What it delivers is smooth, musical, open, and detailed compression - the type that you'd expect from a premium tube opto. I love it's simple, classic layout and never struggle to make it work for my tracks. On vocals, it is masterful! With transparent compression that always moves and flows with all the nuance of the performance, the One-LA avoids a common compression pitfall, unpleasant “gasping”. Same can be said for tracking with bass guitar through it. You get effortless leveling with some beautiful tube warmth, but without any “bloat” in the low-mids that plagues most unworthy and less well-build LA-2A clones. 

IMO there is no better compression type if you're after smooth and musical, and within the 500 series format, the One-LA is just might be the very best we've heard.