Farrell first came up with the idea of HowLoud while he was teaching at Caltech and used Los Angeles as a test area. During these early days, Farrell developed a tool to measure environmental noise on a block-by-block basis. The tool takes into account traffic, air traffic, and other sources of urban noise: factories, bars, and other not-so-quiet businesses. He then used a mathematical model to generate a 3D digital sound profile that takes into account not only sounds at their source but also how they propagate through the city landscape. When the analysis is completed, Each location is assigned a Soundscore that ranks the address based on its noise level, with 50 being very loud and 100 very quiet.
After successfully mapping Los Angeles, Farrell is ready to take his service nationwide and is turning to Kickstarter to secure the necessary funds for this expansion. This expansion targets the 1,000 largest urban areas, where excessive sound can be an issue. This value fluctuates greatly within a city depending on the level of the sound and the density of the surrounding buildings. The ability of the sound to move can have a major effect on the ambient noise level, with crowded areas trapping the sound and open areas at the edge of the city allowing to sound to escape. He also hopes to integrate HowLoud with other real estate services where the Soundscore can be listed alongside other parameters such as price, amenities, and similar services like Walk Score.