What is shop music doing to your brain?
Marks and Spencer has announced it's getting rid of all in-store music. But why did shops start playing music in the first place and what does it actually do to our minds?
If you want to sell hosepipes and spanners, you could play Dolly Parton or Kenny Rogers. To make red wine at an in-store tasting that little bitter darker and deeper, try the thundering sounds of Carmina Burana. To shift more silk ties, it could be worth slipping on Nirvana or Pearl Jam, apparently.
Background music in shops - disparagingly referred to as "muzak" - has been shown to have an effect on our buying habits, but Marks and Spencer has decided to ditch it completely. The company is removing it from all its UK stores, following "extensive research and feedback" from staff and customers.
But is M&S surrendering some of its power to manipulate shoppers?
Shops and restaurants can use music "to target those effects that are most likely to increase sales in a given business", says Adrian North, professor of music psychology at Australia's Curtin University in Perth.
His own research, carried out at Softley's restaurant in Market Bosworth, Leicestershire, suggested diners spent an average of £2 a head more when listening to classical rather than pop music. The likes of Ravel's Bolero and Tchaikovsky's Swan Lake appeared to inspire them to splash out more than Cher's Believe, Club Tropicana by Wham, or Kajagoogoo's Too Shy.
A similar experiment suggested that perceptions of taste altered according to output, so "mellow and soft music" - such as Slow Breakdown by Michael Brook - made the wine taste "mellow and soft". And "powerful and heavy" sounds, like those in Carl Orff's Carmina Burana (once used in TV adverts for Old Spice aftershave) made wine more likely to have flavours that were... "powerful and heavy".
What is muzak?
Muzak started in 1920s when General George Squires patented the process of transmitting music over electrical lines
The name is a combination of "music" and "Kodak", Squires' favourite hi-tech firm
It is known as "elevator music" because of its early use in skyscrapers to calm people's nerves (when elevators were still new and unfamiliar)
In the 1940s, it was used as a musical way of relaxing workers with the aim of improving productivity
M&S, which only started playing music to customers in 2006, is declining to reveal what was on its playlist. The company's Christmas TV ad last year featured Mark Ronson's Uptown Funk.
Muzak has a reputation as being generic, light music, barely noticeable to customers - setting a calm ambience in which to buy things. But the Muzak company that gave rise to the term, taken over by Canadian firm Mood Media in 2004, tailors its playlists to target specific groups of customers, as do several large rivals.
In his BBC Reith Lectures 10 years ago, conductor and pianist Daniel Barenboim complained that background music was undermining "active" listening, creating a generation of people who could no longer concentrate properly on music.
Research at Rutgers University at about the same time suggested music played in shops had no discernible impact on customers' stated mood. But, while it did encourage higher levels of spending among impulse buyers, "contemplative" shoppers actually spent less. Could this help explain the decision by M&S - a business built on dependable repeat custom - to stop playing music?
Defenders of in-store sound say it is no more manipulative than other aspects of store design and management, such as layout, decoration and product presentation.
North says there's evidence that playing Edith Piaf's songs encourages people to buy French wine, rather than South African. "And we know that classical music can drive sales of more expensive products," he says, "whereas country [music] drives sales of utilitarian products."
A few years ago, music writer Paul Stokes attempted to log the songs he heard while shopping in London, but gave up because "it was all either faceless audio wallpaper, or the same pop hits of the day produced by Pharrell Williams".
"Experts say you should only notice the music one in three tracks," he says. "The rest of the time it was there to provide a sense of comfort and calm."
Clothing retailer Foot Locker, serving a predominantly young audience, prides itself on the use of up-to-date, high-tempo music. Hip-hop artist B.o.B played at a store in Atlanta recently.
But Stokes remains sceptical about the effect music can have on brand identity. "It all seemed very scientific until I spoke to a friend about it," he says. "He worked in Tie Rack, where they were sent tapes every month from their regional office that they had to play.
"However, because Tie Rack was a small shop and there were only two of them, when the manager went out he would take off the store music and play his own tapes, grunge, Britpop, etc (it was 1997). He swore they always got more custom with his selections and full albums than with the expert choices."
Tie Rack closed its UK outlets in 2013, but High-Street stores continue to invest heavily in creating the right musical atmosphere. With now at least one exception.
Follow Justin Parkinson on Twitter @justparkinson
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