Developed by Sonnox, the Oxford Envolution is a frequency-dependent envelope shaper that can add presence/distance to drums, piano, guitar, and any other percussive content. With separate transient and sustain sections, the Envolution can radically modify the sound of sources, boosting sustain for added ambience or cutting it for quick, precise gating.
Providing a balance between flexibility and ease of use, the Envolution offers greater control of presence in a mix than an EQ or compressor, and it can also be used to generate negative ratio compression effects.

Sonnox Oxford Envolution Plug-In Key Features:

• Comprehensive control of key shaping parameters including attack, hold, and release
• Separate and frequency dependent control of transients and sustain
• Tilt/parametric targeting of frequencies
• Huge gain ranges: Transients ±24 dB; Sustain -48 dB to +24 dB
• Warmth control for harmonic saturation/tone shaping

More info: http://www.sonnoxplugins.com/pub/plugins/products/envolution.htm