The sonic vocabulary of the pop music recording engineer is not constrained by the architectural acoustics of any space. Equipped with racks and RAM full of signal processing tools, the engineer tries to create musical timbres, textures, ambience, and emotions to support whatever feeling the music inspires. Perhaps nowhere is this departure from the physical to the contrived more apparent than in reverb. Acoustic analogies like the chamber, mechanical simulations like the plate, and the wholly invented spaces of the digital reverb device are part of a family of effects which—inspired by the great halls and opera houses of the world—have an identity and freedom all their own. Reverb time, early decay time, bass ratio, initial time delay gap, and so on become independent variables freely manipulated by the engineer to create sonic ‘‘spaces’’ that may not be physically possible outside of the studio. This paper surveys contemporary pop music production trends in reverb and analyzes them through the lens of the architectural acoustician.