I first noticed this phenomenon in French towns. Not with audio benches, but with mini loudspeakers attached to buildings and piping horrible holiday music in shopping precincts. At first, I thought it was a crass habit that had developed in Calais to ward off English binge-drinking bulk shoppers (not an altogether bad idea), but then I was aurally assaulted in the classier town of Epernay. Anyway, I find it really annoying and inherently disruptive to urban spaces, which are at their most appealing when filled with the usual sounds of city life. Do cities need artificial soundtracks? Who chooses what to play? I'd also be interested in sources on this subject and how it affects the movement within and uses of public space, sound and silence alongside other artifacts of urban planning.
As a matter of fact, it would be quite interesting to know why an architect has decided to create an artificial environment in an open space. Singing benches are quite useless I would say ... they seem to have the goal of adding something to the empty life of people. People are so unsed to stay with themselves, to think about themselves, that a noise is needed everywhere .. you can't even walk outside in silence or at least in the real city noice. Music everywhere, in your ears while you are walking or running, in your car when you move around, now also in open spaces. I think people are so unsed to communicate and to think that they prefer to act like fishes in a ball.
What I would like to do is to sit in that square and spend an afternoon and see who sits on those benches, who are the people who like to live in artificial noice rather to communicate among themselves. Then it would be nice to sit in an open space with no artificial noice and compare the two environments. I think is the only way to see if such sourrindings are really our future.
This article (pdf) might give some insight into what urban planners could be thinking..