After Bowers & Wilkins worked to a tight schedule to complete the elephant subwoofer on time, it was ready to be shipped to Nairobi courtesy of Kenya Airways.
Dr Graeme Shannon arrived in Nairobi two days prior to the loudspeaker to get set up and collect the fieldwork vehicle, which would be used both to transport the Loudspeaker to Amboseli National Park, and to conduct the playback experiments to elephants.
Continuing in the tradition of tight deadlines, the speaker was finally cleared through customs and made available shortly before the end of working hours on Friday 29 May. On Saturday morning all the equipment was loaded into the back of the Landrover and Graeme headed south out of Nairobi towards the border town of Namanga. At this point the tar road ended, and the remainder of the journey (60 miles) was completed on a dirt road. Despite the dust and bumpy road, the journey was made in good time and the elephant research camp reached by early afternoon. The tented camp is located in the heart of the park and enjoys excellent views of Mount Kilimanjaro as well as being frequented by an abundance of wildlife, including elephant, buffalo, lion, zebra and wildebeest.
Once all the equipment was unpacked and the speaker removed from the back of the Landrover it was time to see how it had fared during the 4,500-mile journey from the Bower & Wilkins offices in Steyning, West Sussex to Amboseli National Park, Kenya. The battery terminals were connected and the power was switched on, a low satisfying pop emitted from the speaker confirmed that the amplifiers were in full working order. Once the solid-state recorder (which stores the elephant calls as digital audio files) was connected, it was time to play the first elephant rumble through the speaker. The volume was maintained at a low-level in order to prevent damage to the drivers and provide a cautious start to the testing phase.
Sure enough, a very realistic and high quality rumble was produced and both of the main drivers located on the side of the speaker could be seen moving as they generated the low frequencies that are the hall-mark of the contact call of an adult elephant. The power required by the system was such that the copper wires coming from the battery had to be doubled in size in order to provide sufficient current to the amplifiers. However, once this was completed the Loudspeaker was able to produce elephant calls in excess of 115 db, well above the 105 db that were needed by the researchers for their playback experiments. And they sounded sensational!
Once these tests on the elephant calls were complete, there was just one more thing to try. How did the loudspeaker sound when playing music? Graeme connected his ipod and tried out a few tunes on the resident buffalo that were feeding just outside the camp. While most of the songs fell on deaf ears, Nickelback elicited a definite response with the buffalo stopping to listening for the entire length of one track. Bowers & Wilkins loudspeakers will rarely have had such an unusual quality control test!
The Sussex University researchers are currently consulting with Stephen Entwistle at Bowers & Wilkins so that they can tweak the system to reach the volumes necessary for playbacks of lion roars. One part of their research project involves examining how adept elephant matriarchs of different ages are at discerning more dangerous from less dangerous predators. More on this later…