Meeting the requirements for Enhanced Acoustical Performance is a step up from the prerequisite. For the credit, project teams are required to have a Background Noise Level of 40dBA, whereas the prerequisite only requires 45dBA. The credit also requires project teams to meet Sound Transmission Class (STC) ratings as outlined in ANSI S12.60-2002 whereas the prerequisite does not require projects to meet any STC rating. The biggest difference here is that the STC calculations typically require an acoustics consultant.