My first full day in San Francisco was on Tuesday (July 20th) and I wanted to find a ATI siren because I knew they went off at noon. I found this siren at Bay and Kearny, which is right near the water and the piers. I was heading to the Ferry Building but saw this one and it was close to 12:00 so I recorded this one.
http://www.youtube.com/watch?v=WmX4DSGvPY4
*I will upload all the pictures of sirens I saw on my trip next week, most were down the coast of california for tsunamis and earthquakes*