Could there be a more perfect setting for Sounds of Venice, harpist Rhodri Davies’ contribution to Gregynog Festival 2012 (“Venezia”), than the Impressionists gallery in the National Museum of Wales where the Gregynog collection’s paintings of Venice now hang? Apart from the city itself, you would be hard pushed to find one. It might seem bizarre, at first, to witness a concert of experimental harp music by and inspired by John Cage in this intimate space, surrounded by Monet’s beautiful Palazzo Dario and other Venetian views. Yet, as was revealed during the concert, the relationship between Cage, the city and the founders of the festival is rather special.

In a change to the scheduled programme order, Davies chose to close rather than open the concert with Cage’s Sounds of Venice, the namesake of the concert and the linking force behind the programme. This comic composition, which does not make use of the harp at all, saw Davies casually reclining in a chair, playing a toy horn and extended slinky, all to a backing track of street song, bells and water sounds. Davies’ easy manner and cool assuredness meant he carried off his role effortlessly, allowing the audience to enjoy the unusual piece.

But it is when playing the harp that Davies is truly in his element. Opening with Yasunao Tone’s Ten Haikus of Matsuo Basho, Davies skilfully used Tone’s graphic score, created from the calligraphy of Basho, to effectively demonstrate the diverse range of timbres it is possible to achieve on the harp. Highly reminiscent of Cage’s pieces for prepared piano, crocodile clips and pieces of wood transformed the sound of the harp, removing it entirely from the heavenly sound world with which it is more commonly associated.

The next piece, Laurence Crane's Single Harmony for Rhodri Davies, was equally far removed from conventional harp music. Nowhere to be heard are glissandos or arpeggios. Instead a simple melody is woven over pre-recorded drones. In this innovative yet serene and minimal composition, bass drones are created using E-bows, electronic devices which create a magnetic field setting the strings in motion. The incredibly pure but also very quiet sound that this produces gives an ethereal aura, but quite unlike a plucked harp.

The extreme versatility of the harp was once again displayed in Carole Finer’s radical piece Weave a cloth of gold for me, written for Davies in 2006. This time, Davies used a beater and ribbon to extract unconventional sounds from the instrument. It would be easy to get carried away by the visual aspect of performance, the shock value of these unexpected changes to standard performance practice, but what is so impressive is the beauty of the music Davies creates through these experimentations.

Cage’s Postcard from Heaven could only have been improved by the addition of several other harps (the directions note that it can be performed by anywhere between one and twenty harpists). This would have added another layer to a concert that was by no means lacking variety, but this particular piece would have benefitted from a more stark contrast between the anarchic central section and calmer framing sections. That said, Davies masterfully executed dramatic dynamic contrasts and illuminated even more new dimensions on an instrument that had already surpassed all expectations.

The highlight of the concert was undoubtedly the world première of Davies’ own acqua alta, commissioned by Gregynog Festival this year. Taking its name from the tide peaks that occasionally disrupt life in Venice, Davies evoked images of a harp being played underwater.

In this interesting juxtaposition of old with new, the cutting edge with convention, the ejection from the familiar comfort zone of standard harp repertoire was refreshing. The combination of this ancient instrument with new techniques, century-old images of Venice with the aural soundtrack of modern Venice, was thrilling. One hundred years on from Cage’s birth, Davies will be performing in the Proms concert dedicated to the music of Cage later this year. If this afternoon’s concert was anything to go by, that is a concert not to be missed.