Engineering Sound CSUF - Meng Concert Hall Mark E. Rothermel Principal Rothermel & Associates, LLC Architectural Acoustics Collaborative

Building Acoustic Design to Support the Programmed Uses of the Hall Orchestral Music Romantic, Classical & Contemporary Chamber Music Civic Light Opera Big Band High School Bands Opera Choral Music Engineering Sound = Architectural Acoustics

HVAC Noise Control Quiet Mechanical, Electrical & Plumbing Systems Sound Isolation Walls, Roof, Doors & Windows Room Acoustics Shaping, Materials, Finishes, Moveable Elements Architectural Acoustics

HVAC Noise Control - Criteria

Low Noise Levels Achieved Through: Quiet Equipment Selections Location of Equipment in Relation to Hall Duct Routing, Dimensions and Lengths Slow Airflow Velocities Smooth Takeoffs and Transitions Location of Remote Volume Dampers Silencers and Duct Liner Diffuser/Grille Selections and Sizes Vibration Isolation of Mechanical, Electrical and Plumbing Equipment and Piping HVAC Noise Control

Pressurized Main Duct Low Velocity Air Drops from supply air ‘mushrooms’

Sound Isolation Plan for Sound Isolation Circulation, Lobby, etc. provide buffer zones

Walls Grout-Filled Concrete Block Walls Doors Sound Rated Acoustical Door Assemblies Gaskets on Standard Doors at Vestibules Windows Thick, Multiple Glazing Layers in Airtight Frames Roof Concrete on Metal Deck Sound Isolation

Floors Isolated, Floated Concrete Floor Slab Over Structural Slab Grad Slab with Perimeter Isolation Joints Special Construction Box-in-Box Construction Perimeter Isolation Joints Floated Concrete Slabs Vibration Isolated Gypsum Board Ceilings Sound Isolation

Room Volume Maximized for Reverberation – 400,000 Cubic Feet Shaping All Surfaces Have Specific Angular Orientation, Shape, Radii – Nothing is Arbitrary Finishes & Materials Heavy, rigid, stiff surfaces for bass support Variability Movable Drapes & Banners Movable Canopy Room Acoustics - Basics

Retractable Banners and Draperies Vary the Reverberation Time Room Acoustics - Reverberation

Room Acoustics - Shaping

Balcony Fascia Shaping Shaped & Articulated, Tight Radius Curves Highly Sound Diffusive Counters Focusing of Horseshoe-Shaped Plan

Room Acoustics - Shaping Doubly-Curved, Moveable Canopy Ensemble Attack Articulation Clarity

Grout-Filled Concrete Block Walls Concrete on Metal Deck Roof Rigid Interior Shapes and Surfaces of Heavy Plaster No Diaphragmatic movement All to Support Bass Response Room Acoustics – Finishes & Materials

Acoustic Canopy Directs Sound Toward Audience Facilitates Ensemble by Allowing Musicians to Hear One Another Changes the Direct-to-Reverberant Ratio Room Acoustics - Variability

Moveable Fabric Banners Change the Reverberation Time (RT60)

Quiet Allows High Dynamic Range of Music Isolated No Distractions To or From Neighbors Sound Carefully Defined Interiors Conclusion

Questions?