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that they could be heard by all in the room above the relatively quiet background sounds. Everyone in the room would know where the sound was made and who made the sound. Interestingly, quiet was achieved by the reverberant propagation and enhancement of sounds throughout the room because library users were careful to maintain the quiet soundscape. Traditional architectural acoustical references provide guidance for the analysis of reflected and reverberant sound paths and calculation methods to assess control of excessive loudness and acoustical defects in rooms (Sabine, 1964).
The Carnegie Libraries
The Carnegie libraries were built in the late 1800s and early 1900s in cities, towns, and universities in the United States and abroad to spread knowledge through reading to all citizens as part of Andrew Carnegie’s legacy. Carnegie (see en.wikipedia.org/wiki/Andrew_Carnegie), who made his money by being a pioneer in the steel industry, donated funds to build the library if the community could provide
a site to build the library on and provide funds for staff, operations, and on-going support.
Carnegie libraries were prototypes with a simple acoustical itinerary, straight forward plan, and efficient uses (Figure 1). The main entrance was often in the center of the facade of the building that faced the primary street. There was an entry foyer around which other spaces were oriented. A lecture room where people could exchange ideas and listen to talks about topics of interest was often included, sometimes located on a floor below the main or entry level and sometimes off to the side of the main spaces on the entry level. Back of house, staff work rooms, mechanical spaces, and bathrooms were also included on a lower level or to the sides of the main spaces.
The Carnegie libraries were often one large open, reverberant room built with sound reflective materials, sometimes with domed or vaulted ceilings with large windows to allow daylight into the spaces, similar to early library reading rooms. The librarian performed the role of central information and control where materials could be checked out manually by stamping a card in a pocket inside the cover of the book. The librarian also provided assistance to patrons verbally by helping them with questions about looking up information in the card catalogue. There were no real sonic niches for speaking to colleagues or friends or where conversations could occur
about the library materials people were reading. People had to speak quietly, using their “library voices,” to avoid disturbing the quiet, individual study of others.
Periodicals and newspapers were sometimes located in separate areas where people could come in, read, and leave. People could even engage in a conversation with friends entering or leaving the space without disturbing others in the reading room involved in more serious study or contemplation if enough separation of these areas from the main reading room was provided.
Large, big city libraries in the early twentieth century often had a similar plan, organization, and itinerary to the smaller Carnegie libraries but on a larger scale.
Mid-Twentieth-Century Libraries
Libraries of the mid-twentieth-century often had similar plans to the precedent libraries, but new design trends were changing the shape, structure, materials, and soundscape of the libraries (Figure 2). Architecture of the mid-twentieth- century broke with earlier traditions and brought with it lower, horizontal lines that resulted in lower ceiling heights and more open spaces than the pre- and early modern architecture of the turn of the nineteenth century. The high vaulted ceilings were no longer a popular architectural motif. New materials such as acoustical ceiling tiles and other sound-absorbent finishes, including carpet on floors, replaced the stone, wood, and marble of the precedent
Figure 1. Reading room in a traditional Carnegie library, the Savannah East Henry Street Carnegie Library (Julian de Bruyn Kops, Architect).
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