Now alone, Conrad hears a rhythmic sound reverberating upon the ship's hull. Jack Douglas' 1977-"wall of sound" production lends character to the endlessly reverberating harmonies. It utilizes a synthesized keyboard arrangement to bring about a continuously reverberating heartbeat sound. The song uses reverberating effect throughout its length. A reverberating circuit produces a repetitive output. The single version has a different, more reverberating drum track. Rain gardens have many reverberating effects on the greater hydrological system. It does not normally include deaths caused by the indirect or reverberating effects of conflict. This type of circuit does not have a feedback loop as does the reverberating circuit. Roy Jenkins described it as the most reverberating since Gladstone's in 1860. He also creates the reverberating pops on the introduction of "2 + 2 = 5".