Page 34 - Jul2009

Fig. 4. Seth Horowitz placing the seismic sensor on the iron at the base of the Eiffel Tower Credit: China Blue.
Fig. 3. China Blue monitoring the recording in front of the Jules Verne Restaurant on the ground level. Credit: Seth Horowitz.
recording that was produced (Clip 1).
We also used this same method to record in the sub-
basement. This area that is out-of-bounds to visitors is a room where all of the motors, gears, pulleys and accumula- tors are housed that run the whole system some of which are original and now over 120 years old. We placed the geo- phones on the metal foot bridge that amplified and resonat- ed with the vibrations of the machinery housed on the floor below. There we monitored the chassis that pull the elevator gears and cables and the accumulator that makes a spewing sound as it spills oil to let the elevator ascend (Figs. 5, 6). We also heard the emergency alarm that went off when one of the elevators temporarily stopped and the workers running and yelling as they responded to the alarm. That was when Dr. Horowitz said that I broke the Eiffel Tower. Here a sample of the geophone recording of the carriage in the machine room can be heard. (Clip 2).
Ascending from the sub-basement via a service eleva- tor, we next decided to record from the summit, just in case the weather would prevent such recordings later in the day. At the summit, we positioned the seismic sensor system on the outside railing that runs continuously around the tower on this level. There we captured a separate recording of the wind blowing against the summit at the elevation of about 1,000 feet (Fig. 7).
We also applied this method to the service stairwell land- ing (just under the summit—another area closed to tourists).
In this region are the fire escape stairs and service access areas that are adjacent to the open elevator cages. There we placed the geophones on a metal grating to capture the sound of the elevators going by as they moved within inches of our faces (Fig. 8, Clip 3).
For the ambient sonic recordings, we primarily used the in-ear binaural microphones attached to the DAT for a peri- od of 20 minutes at each location. I assigned a team member to monitor the binaural system and whenever possible, the individual would walk in a snail shell or circular pattern moving from the inside out to capture the ambient acoustics on each level. On the ground level this was an easy walking pattern. This is a large open area where people clustered in groups and we were able to capture street sounds, the sounds of the on-going construction on the lower level of the Eiffel Tower, and visitors queuing up to get into the tower. Listen here to the binaural recording at the ground level (Clip 4).
The snail-shell recording pattern could not be applied in the machine room area because our work area was limited to two narrow staircases and the metal service bridge that over- looks the floor below where the elevator equipment is housed. Although this recording area was physically limited there were fascinating mechanical sounds that we were able to capture (including the emergency alarm). The sounds of the emergency in the machine room were caught on the bin- aural recording (Clip 5).
The area just under the summit is a narrow metal main-
Fig. 5. Chariot pulling the cables in the subbasement. Credit: France Languérand.
Sounds of the Eiffel Tower 33