Blending old with new

The Princeton University Chapel is the religious and ceremonial centre for Princeton University. It was built in 1928 and used by the university to formally open and close the academic year with an interfaith service. It’s also the site of special services of music and thanksgiving and concerts throughout the academic year. Seen as an oasis in the middle of campus, people of all faiths visit the chapel for prayer and meditation every day.

When the Marquand Chapel, built in 1881, was destroyed by fire in 1920, an appeal for funds was issued to construct a chapel in an architectural style based on the 14th-century English Gothic and appointed Ralph Adams Cram of Boston, a leading architect of Gothic revival. When completed in 1928 at a cost of more than US$2m, the chapel – capable of seating 2,000 people – was second in size only to the chapel at King’s College, Cambridge. The oak pews in the nave are made from wood originally intended for Civil War gun carriages. The pulpit, brought from France, dates back to the mid-16th century, while the wood for the pews in the chancel, where the choir and clergy are seated for services, come from Sherwood Forest in England and took 100 people over a year to carve. One of the most recognisable architectural features is the grandiose, 8,000-pipe Mander-Skinner organ designed in the English cathedral style and completely renovated in 1991 in the UK. Needless to say, it's an impressive building.

In 2022, Princeton University decided to completely revamp the chapel’s audio system. The aim of the upgrade was sixfold: to provide clear and intelligible speech for all congregants throughout the sanctuary; deliver acoustically balanced music enhancement throughout the sanctuary seating areas; provide a system that supports a variety of events, including worship, weddings, lectures and music performances; provide the capabilities for broadcasting events; minimise the visual impact of the system within the historical architecture of the building; and provide better audio for worship leaders, the choir, musicians and the organist.

The university appointed New York-based SIA Acoustics to design the system. “The acoustic consultant acts as an intermediary and designs the system because they’re getting the information from the university and we’re working with the consultant to make sure the system is feasible from an engineering perspective,” explains Vero Tabares, marketing director at Washington Professional Systems (WPS). “The project went out to tender in 2022 but we have a great relationship with Princeton and we’ve done a lot of work for them in the past, and so our prior experience certainly helped us complete this project successfully.”

WPS had designed the existing audio system nearly 20 years ago. “One of our engineers, John Fish, had worked on the system two decades ago so he was really delighted that he could work on the project again,” explains Tabares. “The old analogue system was working perfectly – it was just time for us to engineer a digital system that works on the Dante network and is interoperable with other equipment, so it means that the chapel can upgrade consoles, speakers or microphones in the future and it will all be interconnected.”

The system design focuses on two modes of operations, enabling it to be used both with and without an operator. With a technician, the system operates with full capabilities. Without an operator, the system will provide speech reinforcement from the pulpit or chancel with one wired and one wireless microphone, and allows the user to turn the system’s loudspeakers on or off in the nave. Additionally, the second non-operator mode provides a partitioned section of the system for speech reinforcement in the Marquand Chapel. These modes are controlled via touchscreens at separate locations, including FOH mixing, the pulpit and the Marquand Chapel.

The loudspeaker system was designed with the goal of delivering high-quality speech intelligibility and tonal balance for music. With that framework in mind, it uses 13 different self-powered Renkus-Heinz Iconyx series loudspeakers throughout the main sanctuary, located on each side of the altar, on the columns of the nave, on the sidewalls of the balcony and in the Marquand Chapel. Each loudspeaker receives an independent audio signal from the DSP and is programmed with specific delays to act as one unit, creating the effect that the audio is being delivered from the altar.

The Renkus-Heinz loudspeakers feature beam-steering capabilities, allowing sound dispersion from the loudspeakers to be controlled in both the vertical aiming and angle. This capability helps fine-tune the system for highly intelligible speech in a very reverberant and reflective space.

The design also consists of Fulcrum Acoustic’s RX599 Series loudspeakers suspended at the bottom of the chandeliers in the nave, crossing and transept sections. The loudspeakers are practically invisible as they’ve been integrated so well within the chandeliers. These loudspeakers provide envelopment support for musical and choir performances.

Additionally, Fulcrum CX8 Series loudspeakers are placed in the chancel’s chandeliers above the choir section and act as flown monitors to provide audio from above the choir. This configuration allows the choir to hear the spoken word from the pulpit and lectern and also hear themselves and other musicians during performances. The system also incorporates six dBTechnologies DVX DM28 portable floor monitors for the choir and musicians.

The audio system is powered by a set of QSC Q-SYS CX-Q Series networked powered amplifiers and a Q-SYS Core 510i integrated DSP. FOH mixing uses an Allen & Heath Avantis digital mixing console for mixing, signal routing and control. The Avantis is a 96kHz/64-channel/42-bus digital mixer that is fully configurable and allows settings to be stored and recalled based on user profiles.

A series of microphones are used throughout the chapel, both for broadcast/recording purposes and for audio amplification. In the choir section, two pairs of DPA Microphones 4011C stereo microphones are closely spaced out, with one pair facing the chancel and the other pair facing the crossing/nave. Earthworks FW730 cardioid microphones have been installed facing the choir section for speech, music and choral applications. For instrument audio pickup in the choir section, Audix SCX, D6, MicroBoom and DP5 microphones as well as an Earthworks PM40 system are connected to a portable rack under the pulpit and can be used for events requiring additional capture capacity. Both the pulpit and lectern locations use Audix MicroPod goosenecks. A Shure Axient wireless microphone system with two Shure AD4Q receivers are used throughout the chapel to support a series of Shure ADX2, ADX1 and TL46B wireless microphones.

Finally, a new assisted listening system from Listen Technologies provides two modes of operation for audience members, using either dedicated ListenTech receivers or their own smartphones as headsets. The system uses ListenTech’s combined Wi-Fi/RF transmitter technology on the chapel’s Dante network to deliver wireless audio with minimal interference and latency. This design configuration reduces the number of transmitters required and covers a broader portion of the seating area.

Although the chapel is based on the old English Gothic cathedrals, it’s not unusual to find buildings in this style in the US, particularly in the northeast of the country. “In the late 1800s and early 1900s, there was a movement to design chapels and school buildings in the US in this Gothic style, and this included several chapels on older university campuses. So it was no surprise that the number one goal from the university and the acoustic consultant for this project was that we had preserve the historic quality and visual aspect of the chapel.”

WPS employed a tiered escalation process to identify potential modifications to the chapel’s infrastructure and sought guidance from either the project architect or Princeton’s preservation team. The use of this tiered process ensured that the WPS team minimised the effects of the installation on the chapel’s irreplaceable stone and woodwork, and created an open dialogue between the project staff.

Additionally, the university emphasised that the chapel remain open throughout the project for daily mass and events. To maintain normal operations, WPS created staggered shifts for the field teams that followed the chapel’s daily activities and provided constant updates to minimise any scheduling conflicts. “One of the caveats for the project is that we couldn’t interrupt the day-to-day running of the church and its services. It meant we had to have staggered schedules or we had to work in parts of the chapel that weren’t currently being used. It also meant we had to work nights in some cases, particularly when it involved running or pulling cabling or the physical installation of microphones or speakers.

“We’re incredibly grateful to Princeton and SIA Acoustics for the opportunity to be involved in this extraordinary project,” concludes Tabares. “The chapel is very meaningful and has a huge impact on the campus. There’s a lot of Gothic-style buildings surrounding the chapel but it stands on its own in the middle of a plaza where students congregate after class, and when the sun shines on it, it’s a beautiful piece of architecture. Inside, the new system achieved its goal of blending modern and advanced capabilities with flexible, easy-to-use operation, plus it has enough headroom to be used for a wide variety of events with no drop-off in quality or sonic clarity. The upgrade has elevated the overall speech intelligibility, improved choir and instrumental clarity, and expanded the recording capabilities, all the while sticking to the original goal of minimising the visual and physical impact on the historic building.”