When the Hard Knee response is used with RMS mode, the compressor operates in a more clinical way with a more defined transition between under threshold and over threshold - this is better suited to limiting style compression. A small amount of the soft knee curve is still retained keeping the sound reasonably natural but with no modification of the compressor envelope. This means that attacks are more aggressive, but it also allows the adaptive nature of the RMS detection to operate to its fullest extent. This mode is good for natural sounding limiting of speech. With the “Vintage” switch active and the default Soft Knee response selected, the compressor employs a dual time constant, linear attack profile. This produces extremely subtle attack and release curves during the onset of compression that are largely independent of the envelope control settings. As the compressor is driven harder (i.e. signals further over threshold) the soft knee effect reduces, gradually returning manual control of the attack and release times to optimise capture of larger transients. Like the RMS modes, this compressor mode is very adaptive making set up of the envelope controls relatively easy. The peak sensing, however, increases harmonic overtones, which add a “Vintage” brightness and sparkle to the programme, producing extremely transparent and lively sounding compression of acoustic instruments. When both the “Vintage” and “Hard Knee” switches are selected, the compressor operates with more precise envelope control and a defined transition between under- and over-threshold. This produces aggressive compression that gives fast control of extremely dynamic material. It can also be used to add colour to low frequency signals making it ideal for controlling instruments such as bass guitar. With the highest ratio setting, this mode allows the compressor to effectively be used as a limiter.