A joint production between Cameron Macintosh and Stage Entertainment, the venue's owner, this latest version of Mary Poppins features an outstanding cast of 40 and stars actress Noortje Herlaar as Mary, who won the part role as a result of her performance in an 8-week TV talent show "Op zoek naar Mary Poppins" (Searching for Mary Poppins), by Dutch broadcaster AVRO.

The new sound design by Paul Groothuis and his team employs a number of techniques new to both the show and the venue, with the emphasis on clarity and aimed at delivering the optimum result within the theatre's circular floor plan. Originally home to a circus, the theatre is effectively a domed cylinder with a rectangular stage protruding from one side, and has been hosting performances for over a hundred years. Paul Groothuis worked with Associate Sound Designer John Owens, and Production Sound Engineer Tim Stephens, designing a distributed four-layer solution, which delivers the sound to the audience via four independent loudspeaker systems - covering the vocals, orchestra, sound effects and surround signals respectively. The vocal system is in turn split into an A-B configuration - comprising two parallel but independent systems - preventing the phase errors caused by two microphones in close proximity, such as during a duet. In spite of the number of loudspeakers and the amount of sound equipment involved - all supplied by UK and European theatre specialist Orbital Sound - the installation is largely invisible within the auditorium, apart from the low-profile mix position at the back of the stalls, housing the main DiGiCo D5T and D5TC console and the Yamaha DM1000 sound effects mixer.

Paul's extensive background in sound design includes some 19 years at the National Theatre in London, with subsequent credits for numerous plays, musicals and dance productions in the West End and Europe. He explained his philosophy for this production:
"Mary Poppins is my first show at this venue. The space presented some obvious challenges, and a few notorious ones, but fortunately the area below the dome is now broken up by several surfaces, minimising reflections generated by its shape.

"As this is more of an underscored show, rather than a totally sung-through musical, the intelligibility of the spoken dialogue is critical. I tend to draw on my drama background, and prefer to use a distributed system rather than a full-on front-of-house approach. With a distributed system, you can keep the volume down and the clarity high. You can't just do everything loud - drama needs light and shade, and you don't necessarily want to push everything through the FOH.

"Working with multiple discrete signal paths provides considerable flexibility, enabling us to optimise each path, step by step. In this case, with just the cast on stage for the first rehearsal phase, we could establish and fine-tune the vocal system, without having to compromise the set-up when the 15-piece orchestra arrived some two weeks later. The vocal system remained unaffected, while we concentrated on setting up the orchestra system to its best advantage. Similarly, the sound effects and surround systems could each be installed and adjusted without compromising the other.

"In addition to the workflow practicalities, a further advantage of using split systems is the amount of available headroom. We can run each system at its optimum level, with plenty in hand, contributing to the open quality of the overall result. The vocal A-B system has similar advantages, beyond its obvious phase-error prevention role, as in the full-cast numbers we can route half the radio microphones through the A system and remainder through the B - again, this contributes to the achievable clarity, by reducing the complexity and demands of the signal going through any one system."

Beautifully hidden behind gauze-screened scenery on both sides of the proscenium, the core of show's sound design employs 28 Meyer M'elodie arrays for the vocal system, controlled by Meyer Galileo 616 loudspeaker management systems. The loudspeakers are arranged with a 2 x 7 hang either side of the proscenium, and with each pair of hangs split to deliver the A-B configuration. Across and just below the front edge of the stage are a series of vocal front fill loudspeakers, comprising twenty d&b audiotechnik E0 units, installed at approximately one-metre intervals and configured in A-B pairs. Two pairs of Meyer UPA1Ps are also used a little way into the auditorium, firing down from the roof. For the surround system, Paul uses an initial ring of sixteen Meyer UPM1Ps, plus a final row of twelve E0s that act as surround delays.

To prepare for the show's fit-up, which began back in mid February, Tim Stephens spent some three weeks at Orbital Sound in London, working with the company's senior engineer Dan Bailey. The fit-up process took a month, with dry tests taking place during the fourth week, followed by the cast on stage for the subsequent two weeks and then the two weeks of previews. Tim, responsible for translating the kit list into a physical reality, commented: "The ability to work closely with Orbital in advance and see their approach to a project of this scale contributed considerably to a smooth load-in. The preparation covered the complete signal flow - from the 48 radio microphone channels, plus the 6 reverse radio links for the sound-effect loudspeakers hidden around the set, through all the cabling infrastructure, the consoles, plus the radio and video comms, to the 150+ loudspeakers."

John Owens added his perspective on the production, highlighting its collaborative spirit:
"A particularly important aspect of this production is the way in which all the creative teams have worked together. Paul, Tim and I have worked alongside each other on several Cameron Mackintosh tours, including Mary Poppins' UK tour, and there's no real hierarchy - everyone just gets on with the job. It's very much a collaborative democracy, and our approach to the sound is more about discussion, and inviting constructive input, than telling the crew what to do. Paul's philosophy is certainly one of empowering the operator, and giving them a creative say in the proceedings, which in turn helps to generate more pride in the end result. We actively avoid taking a more dictatorial approach. The whole team here has been fantastic. Marcel Kroese, Head of Sound for the Circustheater, is the Number 1 mixer for the show, and is one of the very best. He's worked on a number of musicals here, including Tarzan, Beauty & the Beast, and Lion King."

Indicative of Orbital Sound's increasing scope in continental European theatre, Mary Poppins represents Orbital's second foray into the Circustheatre, previously supplying the sound for Stage Entertainment's production of Tarzan in 2007.