Roberts pulled out a vinyl recording he had bought as a teenager at an op-shop a decade earlier and said: ‘‘Remember this?’’

Holdsworth certainly did.

His parents had taped the music, Mike Oldfield’s Tubular Bells, and played it when they were on long drives.

Oldfield had come up with the idea as a teenager of writing an album-length piece that used many musical styles and recording it with himself playing all the instruments.

Tubular Bells, generally described as a Celtic folk-rock epic, was recorded in England in 1973 with the backing of a record-shop owner, Richard Branson, and was the first release of a company he founded, Virgin Records.

The album was a worldwide bestseller, with about 15 million copies sold, and set 19-year-old Mike Oldfield on a successful musical career, and Branson on the path to wealth and power.  

As they listened to the recording on the cold 2008 night, Roberts and Holdsworth came up with the idea of playing it on two guitars as a concert piece. That was soon replaced by a more ambitious concept.

Oldfield had played all but three of the 20 instruments used in Tubular Bells, with the music for each instrument recorded in turn and the tracks put together.

Why couldn’t they emulate Oldfield, the Katoomba mates thought, but play all the instruments at a public performance? That was the birth of Tubular Bells for Two, a staging of the work that has the pair moving rapidly between 26 instruments carefully placed in the performance area.

 Roberts and  Holdsworth spent nine months developing the show, then gave Tubular Bells for Two its first staging at the intimate theatre in Katoomba’s Clarendon Guesthouse on Good Friday in 2009. They picked that date because they thought it would be a quiet night and they only expected a few friends to attend. In the event, the show played to a packed house of more than 100 people, and has become a hit internationally.

A prizewinner at the 2010 Sydney Fringe Festival for best musical moment, it has played at other Australian and New Zealand festivals since then, was performed at the 2012 and 2013 Edinburgh Festivals, toured Europe last year, and is currently in the United States before beginning an Australian tour in Newcastle on January 31.

The Newcastle show will be staged on the Fort Scratchley Parade Ground, with the two men performing in bare feet as they dash from one instrument to another. The amount of movement the show involves has them using fingers and toes adeptly.

Audience members will be seated on the ground, with rugs and low camp-chairs recommended as carry-ins.

The show will have an interval at the point where the first side of the LP record ends, midway through the 50-minute work.

Though Tubular Bells for Two emulates the sound of the original recording,  Roberts and  Holdsworth use many instruments that weren’t around when Mike Oldfield put the work together.

The inventory includes electric, bass and acoustic guitars, a synthesizer, piano, glockenspiel, drum kit, kazoo, tin whistles, bodhran, electric organ, loop, distortion and delay pedals, their own voices and, of course, tubular bells. And they keep making changes when new instruments come on the scene.

The pair, now in their mid-30s, work individually with other musicians and bands, and are accomplished in areas other than playing instruments.  Roberts, for example, has composed scores for theatrical productions, including King Lear, Hamlet and The Ultimate Murder Ballet Musical. 

 Holdsworth has been a performer and musical director for stage works, and has composed scores for dance productions and short films. But they have been delighted by the response to Tubular Bells for Two, after playing close to 150 performances around the world. Their season at the 2012 Edinburgh Festival coincided with the London Olympic Games, where Oldfield played some of the music from Tubular Bells in the opening ceremony. That helped boost the audiences for the Edinburgh shows.

And when they performed at the 2013 Edinburgh Festival, they also did a show at a 1000-seat venue in London on May 25, the 40th anniversary of the release of Oldfield’s LP, with many of the packed audience members in tears as they enjoyed the way Roberts and Holdsworth had given an added vitality to the music while staying faithful to the composer’s original score. Oldfield said in an interview  that he thought their interpretation was ‘‘real cool’’.

Tubular Bells for Two can be seen at Fort Scratchley at 8pm on Saturday, January 31. In the event of wet weather, the performance will be at the Civic Theatre. Tickets: $30 to $38. Bookings: Civic Ticketek, 4929 1977.