Sliding on their sock-clad feet, a gaggle of children squeeze themselves under the belly of the Steinway as the Norwegian pianist Leif Ove Andsnes invites them to place their palms on the soundboard and feel the vibrations.

When Andsnes launches into a stormy cadenza from the second movement of Beethoven's 3rd Concerto, the children in their makeshift den squeal with delight and surprise. Some point to the pianist's quivering trouser leg and his shiny black shoes pressing on the gold pedals. Others shiver at the strength of the vibrations that run through the gleaming grand piano into their bodies – a sensation that 11-year old Arijan Zagragja later describes by producing a loud and elongated "brrrrrr" while running his fingers over his body in a rippling motion.

All of the eight- to 11-year-olds present in the Cologne Philharmonic have some sort of hearing disability and several of them, such as Arijan, are profoundly deaf. The children have been taken under the wings of the musicians of the Mahler Chamber Orchestra who, together with Andsnes, have launched Feel the Music, which aims to open up the world of music to hearing-impaired children across Europe.

"When the idea was first mooted, I thought what can they possibly get out of the music," Andsnes says. "But after experiencing how the children react to the music I quickly realised I had been far too closed-minded."

Studies show musical vibrations can have as much of an impact on the brain as real sounds, and that exposing deaf children to music early on can stimulate their brain music centres. The MCO and Andsnes have teamed up with Paul Whittaker, a profoundly deaf musician, who runs the UK charity Music and the Deaf.

"It's very rare that deaf children get the chance to work together with professional musicians, and especially with an orchestra," Whittaker says. "Not only does it open up a new world to children with hearing handicaps, it also takes musicians out of their comfort zones and makes them think anew about how they hear and understand music."

Deafness, he stresses, "is no barrier to making or appreciating music. You can appreciate musicality in a multitude of ways, through vibrations, gestures, body movements, rhythms and by reading music on the printed page."

Feel the Music is part of the MCO's Beethoven Journey concert series, which it is taking to 40 European cities between now and 2015. Part of the project examines the way Beethoven's own deafness – which began when he was in his 20s and left him profoundly deaf and his career as a virtuoso pianist in tatters – not only brought him to the brink of despair but greatly influenced his compositions.

"When he wrote for the piano, the deaf Beethoven became obsessed with being able to feel the vibrations, so he created lots of trills – the fast repeated notes next to each other. He also used long stretches of pedal to create huge vibrations of sound as well as extreme registers, very high up and low down notes," Andsnes says. He believes these techniques make Beethoven's music more communicable to those with impaired hearing.

Children touch the back of an instrument as the orchestra plays. Photograph: Timothy Fadek for the Guardian

During the Cologne workshop the pianist furnishes the children leaning on and sitting under the piano with plenty of trills and long pedal sections. "When he presses a key, the hammer strikes a string which then vibrates," says Fabian Schurf, 10, who has been profoundly deaf since birth. He stands at the piano resting his arms on the strings. "The feeling runs up my arm and down into my feet. It's all warm and fuzzy, and feels quite good," he says through his teacher in sign language.

Leon Zagrija, nine, who has partial hearing, enjoys the kettle drums best of all. "I feel them in my stomach," he says as the class is asked to spread out and seat themselves randomly between the musicians on the stage. "It makes the hairs on my arms bristle." He later goes to stand by a double bass, clutching the back of the instrument as if he were hugging a large soft toy, and touching the spike on the wooden floor which emits enormous vibrations.

Eight-year-old Teresa Holtkamp, whose hearing was impaired due to numerous infections of the middle ear as a baby, is also drawn to the drums. Her mother, Ulrike, says she has already seen over several years how music therapy has helped to improve her daughter's ability to communicate. "It's enabled her to develop skills of perception and expression. Today listening to the Beethoven she was very aware of when it was joyous and mournful," she says.

Emma Schied invites the children to blow into her oboe, whose vibrating reeds tickle their lips, and to feel the whoosh of air coming through its bell. "It makes me tingle," says Azad Tabur. Schied, one of the 45 core members of this exuberant travelling orchestra, says involvement in Feel the Music does not just influence the children. "Our ensemble travels around the world and performs with the best conductors and soloists. But this will probably be some of the most important work we will ever do," she says.

"If you're giving children with hearing disabilities access to a better way of expressing themselves through music, the experience can only enrich you as a musician and bring you closer to the music."

Later, a tour of the the Philharmonic offers the children a glimpse of the engine rooms of a concert hall, including the conductor's shower, the cough sweet supply, the stage manager's booth, and the artists' dressing rooms. Then, with strict instructions not to clap between movements, the children take their seats in the heart of a fee-paying audience, and are urged to lean on the wooden arm rests to soak up more of the vibrations as they watch and feel the MCO and Andsnes perform.

At the close of the 3rd Concerto, Azad, who cannot detect any notes in the upper register, springs to his feet and wolf whistles in the direction of the stage, to the mild embarrassment of his dad but to the obvious delight of the musicians, some of whom wave back.

• The Mahler Chamber Orchestra and Leif Ove Andsnes will perform The Beethoven Journey at Symphony Hall, Birmingham, on Tuesday 20 November from 8pm. The concert will be broadcast live on BBC Radio 3.