It's unfair to call de la Mancha bathtub a compressor. It wears too many hats for that, handling multi-band compression, multi-layer parallel compression, series compression, mid / side compression, Left / Right compression, RMS / Peak detection, side-chaining, look-ahead, limiting and maximizing, all with metering and clip counting. Heck, it probably unawarely handles certain kinds of compression that don't exist yet.

Thus, it is not a compressor. It is two very flexible and configurable stereo compressors that you can route in series or parallel. For the option-hogs out there, it also allows you to split the input signal into high / low frequencies or full band.

Fast Features:

• Two band multi-function compressor with comprehensive metering
• Flexible controls allow use as a compressor, limiter or maximizer
• Can be used as a single band compressor, dual band compressor, dual parallel compressor or dual series compressor
• Two bands can be split high / low freq or full spectrum
• Two bands can be in parallel or series
• Fully adjustable frequency split point with adjustable overlap/gap of bands
• Each band has a full set of independent compression controls for different compression flavors in each
• Each band has stereo balance for independent Left and Right channel compression
• Each band has mid / side stereo narrow/width control, which can be used to narrow the low frequency and spread the high, or have independent mid / side compression
• Either or both bands can use side-chaining to drive the compressor from an external signal
• Either or both bands can be muted to help with sound design or save CPU in single band mode
• Attack / Release curve can be linear or non-linear
• Stereo input detection can be linked or unlinked
• Input detection can be filtered to reduce distortion at short release times
• Input detection can be stereo average or max level
• Input detection can be Peak or RMS level with adjustable window
• Optional soft limit at final output
• Look-ahead defined by user in ms
• Wet / Dry mix control allows blending of dry uncompressed signal for NY style parallel compression
• Metering for each band and combined output, covers stereo input, output and gain, gain reduction and clip indicator / counter, with adjustable sensitivity. All meters show actual and peak levels

By the way, Bathtub may significantly increase the volume of your audio. Take precaution when switching through presets because some are louder than others, especially when the maximizer function is on. You'll shoot an ear out.