You just heard the PC-2A Photo-Optical Tube Compressor from Effectrode, a company known for unique, tube-powered tone machines. The Effectrode Compressor is likely to be the quietest, most natural sounding compressor / limiter you can put on your pedalboard. NOS military-grade subminiature tubes power this pedal, running at real amp plate voltages for a warmth and musicality you normally wouldn't find outside of a vintage LA-2A. 100% analog circuitry, with audiophile components, keep the signal pure and the noise floor nonexistent, while a photo-optical gain control prevents "pumping" and other unnatural compression artifacts. For a thicker sound you can flip the toggle switch on top, putting the Effectrode Compressor in peak limiter mode, yielding a tone that's perfect for the Knopfler-style picker. The Effectrode PC-2A Compressor 's high headroom and transparent character means it's also great for bass, acoustic guitar, vocals, or anything else you might want to run through it. - http://proguitarshop.com/store/effects-compressor-pedals-c-602_87/effectrode-compressor-p-2713