The McCallum Theater in Rancho Mirage, California is one of the busier performing arts centers in the country, playing host to a wide variety of professional touring artists, from jazz to contemporary pop, and Broadway touring productions to classical performances. Ranked in the top 70 performing arts centers worldwide in 2018*, it has earned a place in an elite group given its relatively intimate size.
Opened in 1988, the theater has seen several improvements to their audio system over the years. A JBL Professional VerTec VT4888 line array system was installed in 2005 to offer better coverage and higher impact, which served the theater well throughout the years, but by 2018 the system was aging as compared to the current systems and technologies audio touring professionals were using.
The timing was a perfect opportunity to upgrade to the JBL Professional VTX A12 line array enclosure, part of the VTX A-Series. The VTX A-Series is a state-of-the-art design using the newest generation drivers and components, a unique and versatile rigging system, and the highest level of sonic performance. Introduced in 2017, the A12 features a complete redesign of the JBL Tour Sound approach. After investigations into qualified products that would be correct for the venue and its requirements – and hearing the A12 array system at the new HARMAN Experience Center – Jim Anderson, Audio and Video Director at the McCallum, and Robert Patrick of IPR Services, the system integrator, decided on the VTX A12 as the correct choice.
Installing the A12 arrays in the McCallum’s stage wings required enlarging the proscenium opening that houses the left and right main array positions. This was no small task, as the aesthetics of the room and the comfort level of the patrons and season ticket holders had to be respected. The system that was needing to be replaced utilized an eight-box line array system and the replacement was a ten-box system. Additional enclosures would better address the included vertical coverage demands (the angle defining the front row to the rear balcony row) of the combined audience areas and although the new A12 enclosures are shorter, the complete arrays were taller and wider, therefore the loudspeaker openings had to enlarge.
The buildings alterations – flawlessly completed by the IPR installation team – meant the look and feel would be completely familiar and virtually unchanged to most season ticket holders. JBL Pro VTX S28 dual 18” subwoofers added in permanent stage-deck locations created greater low-frequency impact without impeding precious floor space using portable subwoofers. Additional subwoofers added to the existing center cloud positions in the ceiling allow the two levels of subwoofers to create a very rich and immersive low frequency experience throughout the room.
*Pollstar Top 200 Theater Venues – 2018 Year End Rankings
Audio Performance Targets
One of the required system performance improvements was better high-frequency extension with improved coverage and sound penetration to the main floor rear area, under-balcony mezzanine, and upper balcony sections. Working closely with the HARMAN Pro Applications Team using the Ease™ electro-acoustic 3D modeling program and the JBL Professional VTX Line Array Calculator (LAC) , the defined array shape would offer noticeable coverage improvements to these areas.
What is a Line Array and how does it differ from a conventional pro audio speaker?
Audio system designers use line arrays to provide more even volume and consistent audio coverage from the front seats to the rear audience areas. The VTX A12 enclosure splits the entire audio spectrum into three sections: low, mid, and high frequencies. When you create a vertical line of these components, and have the distance between them close enough, they acoustically couple to function as a single tall loudspeaker (the McCallum’s A12 arrays are over 11’ tall) that allows you to modify its shape and to make volume adjustments to groups within the array.
- The shape part is created by the adjustable vertical angle between enclosures; smaller angles and more overlap at the top of the array allow these speakers to project sound further, where larger angles at the bottom of the array spread the sound over a greater number of seating rows in the near area. These speakers at the bottom of the array – at a closer distance to the front seats – cover more rows because of this wider ‘splay’ (angle between enclosures). The speakers at the top of the array use less box-to-box splay angle and have more vertical pattern overlap (being a further distance to the balcony seats, allowing this tighter pattern to naturally project energy further). These two factors allow the shape and near/far volume ratio to offer a more consistent experience to the entire audience. This example from the JBL VTX Line Array Calculator (LAC) shows a side view of the three audience planes and the resulting audio waveform (shown in blue) that has been ‘shaped’ to better address the audience seating geometry (seating areas shown as three thinner red lines at ear level).
- Line Arrays do not lose acoustic energy as quickly as conventional loudspeakers. A standard loudspeaker loses 6 decibels (dB) for every doubling of distance being a spherical sound source. A line array loses only 3dB for every doubling of distance being a cylindrical sound source. Certain frequencies act slightly different, but the bottom line is that line arrays have the ability to keep the near to far audience ratio more consistent, providing a better experience for a larger percentage of the paying audience. The adjustments that the sound engineer makes translate correctly to a wider percentage of the audience – cheap seats included!
System Tuning and Commissioning
Preliminary adjustment and final system tuning dates were attended to by IPR personnel, theater staff, and HARMAN Professional applications and tour sound personnel. JBL Pro Tour Sound team veteran Raul Gonzalez flew in for the final adjustments, and his experience and knowledge of the VTX Systems allowed things to progress smoothly and efficiently. Truly a ‘Pro’s Pro’, Raul has optimized systems, trained personnel, and flown P.A. anywhere from the Grammy Awards to Radio City Music
Hall, and every place in between. With laser distance/angle checks complete, to verify the near and far audience distances for LAC accuracy, JBL Performance Manager™(PM) was connected into the audio network for system control and adjustment. The ability of Performance Manager to interact directly with all Crown I-Tech amplifiers and the LAC program makes real-time changes to the amplifiers much more streamlined than earlier methods. Loudspeaker impedance loads can be monitored, amplifier headroom viewed (how much go-go juice is left before maximum output is reached), and built-in functions to address the size and characteristics of the array can be set prior to the final system adjusting for room acoustics and music listening for confirmation that all is correct… and musical.
The New System Completed
Listening at various points in the room verified that both the design and optimization of the system to the acoustic environment achieved all the goals set by the client. Anderson, who is also a world-class live audio engineer with over forty years behind consoles, is also the primary mixing console operator. The additional high-frequency extension of the new A12 system immediately was apparent, bringing new life to familiar and trusted listening tracks.
“The new VTX A12 system has reinvigorated my joy of live mixing”, said Mr. Anderson.
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