In the process of developing the ADL 700, which uses the same high-voltage tube preamp found in the award-winning ADL 600 (codeveloped by PreSonus and Anthony DeMaria), Creel came up with a new design for a very special solid-state preamp that uses a Class A hybrid input stage with discrete transistors and the latest-generation, low-distortion operational amplifiers. Everyone at PreSonus who heard his prototype was so blown away by its transparent, detailed, clear sound that the new preamp immediately became an in-house legend. By popular demand, Creel"s superb preamp became the heart of the new RC 500, named "RC" in Robert Creel"s honor. The RC 500 combines the custom-designed FET compressor and semi-parametric EQ circuits that Creel developed for PreSonus" highly lauded ADL 700 tube channel strip with his new ultra-low-distortion, high-gain, solid-state Class A preamplifier design, which delivers consistent, repeatable, transparent, detailed audio. A balanced analog insert sends the source signal out of your RC 500 before the compressor, EQ, and Master Gain stages and returns the signal directly to the compressor stage, allowing you to add external processors.