Background
Located in the heart of Princeton’s campus, the University Chapel welcomes the University and greater community for prayer, meditation, and public events. The chapel is the site of University ceremonies, interdenominational services, weddings, and funerals for alumni and members of the University, and special services of music and celebration.
The Chapel was completed in 1928 and designed by influential American architect, Ralph Adams Cram, in the Collegiate Gothic style and is widely considered as one the largest university chapels in the world.
The Chapel’s sanctuary features many unique art installations, including 25-foot ceiling-mounted silk paintings by Juanita Y. Kauffman, Threshold paintings that were commissioned for the University’s 250th anniversary in 1996, and the Ascent: Blue River paintings. One of the recognizable architectural features of the Chapel is the grandiose, 8,000 pipe Mander-Skinner organ designed in the English cathedral style and completely renovated in 1991.
The Chapel has gone through a series of renovations in the early 2000s, including a two-year restoration, which saw the revitalization of the intricate stained-glass windows and repairing of the stonework and masonry. These series of improvements were considered the “largest such project in this country in the last 25 years” according to Bob Kelly, site superintendent for the Masonry Preservation Group, Inc. and general contractor for the entire project.
In 2022, Princeton University sought an AV integrator to completely revamp and update the Chapel’s audio system with the following goals:
- 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 of events
- Minimize the visual impact of the system within the historical architecture of the Chapel
- Provide better audio for worship leaders, the choir, musicians, and the organist
System Design
Working together with SIA Acoustics, an audiovisual consultant and the system designer for the project, WPS engineered and integrated a complete audio system with multi-purpose capabilities for a variety of users and events.
System Operation Modes
The system design focuses on two modes of operations, enabling the system to be operated 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 allow the users to turn on or off the system’s loudspeakers in the Nave. Additionally, the second non-operator mode provides a partitioned section of the system for speech reinforcement in Marquand Chapel. These modes are controlled via touchscreens at separate locations, including the FOH (front-of-house) mixing, the pulpit, and Marquand Chapel.
Loudspeaker System
The loudspeaker system was designed with the goal of delivering high-quality speech intelligibility and tonal balance for music. With that framework in mind, the system utilizes 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 at the Marquand Chapel. Each loudspeaker receives an independent audio signal from the DSP and are 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 the very reverberant and reflective Chapel.
The system also uses 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 spoken word from the pulpit and lectern and also hear themselves and other musicians during performances. The system also incorporates six dB Technologies DVX DM 28-series portable floor monitors for the choir and musicians for use during events.
The audio system is powered by a series of QSC Q-SYS CX-Q-series networked powered amplifiers and a Q-SYS Core 510i integrated DSP.
Audio Console
The front-of-house 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 profile. The Avantis console also features a DA 128×128 expansion. Allen&Heath was also selected for its uniformity with other consoles throughout the Princeton University campus.
Audio Network
The Chapel’s audio system uses a DANTE-based network to transport audio signals throughout sanctuary, choir, and altar. The configuration allows the system to move audio signature efficiently with very low latency and lower cost compared to analog distribution. With DANTE, operators have the ability to access all of the systems inputs and output, and route each signal as needed, including to specific loudspeaker groups.
Recording and Production System
A new recording production system was designed to expand the capabilities of the existing streaming and broadcast studio and includes ProTools DAW (digital audio workstation) compatibility with a Waves plugin and DANTE network interface through a 12-core Apple Mac Pro workstation. The recording system captures audio from a series of microphones installed within the Chancel and Crossing/Nave. The ProTools system can be operated from the front-of-house section via DANTE. The production studio also incorporates a pair of Neumann KH80 monitors.
Communication System
The production team operates in many areas of the Chapel and needed a way of communicating between the staff during events and services. A Clear-Com system using both wires and wireless stations was integrated, with the fixed (wired) communication ports in the front-of-house, vestry, choir green room, and broadcast studio locations.
Microphone System
A series of microphones are used throughout the Chapel, both for broadcast/recording purposes and for audio amplification (speech, instruments, and choir).
In the Choir section, two pairs of DPA Microphone 4011C-series stereo microphones are installed, closely spaced, with one pair facing the Chancel and the other pair facing the Crossing/Nave. These are used for the audio recording system and are suspended above from a support cable. Earthworks FW730 cardioid microphones are installed facing the Choir section for speech, music, and choral applications. For instrument audio pick up in the Choir section, Audix SCX, D6, MicroBoom, and DP5-series microphones as well as an Earthworks PM40 microphone 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-series gooseneck microphones.
A Shure Axient wireless microphone system with two Shure AD4Q receivers are used throughout the Chapel to support a series of Shure ADX2, ADX1, TL46B wireless microphones. This system provides excellent coverage and fidelity with minimal interference and very long battery life.
Assisted Listening System
An all new assisted listening system from ListenTech was installed and 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.
Challenges
The Princeton Chapel, located within the Princeton Historic District, is considered a contributing property, enhancing the district’s historical and architectural significance. Due to its historical status, modifications or alterations to the stone walls or wood surfaces of the Princeton Chapel by the WPS team, required careful coordination with the project architect and Princeton’s historic preservation team.
Given these requirements, WPS employed a tiered escalation process to identify potential modifications to the Chapel’s historic 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 minimized the effects of the installation on the Chapel’s irreplaceable stone and woodwork, and created an open dialog between the project staff.
Additionally, the University emphasized that the Chapel remain open throughout the project for daily mass and events. To maintain normal operations of the Chapel and prevent interruptions, WPS created staggered shifts for the field teams that followed the Chapel’s daily activities and provided constant updates to minimize any scheduling conflicts.
Outcome
In October of 2023, WPS delivered a fully integrated, digital audio system to the Princeton University Chapel that elevated the overall speech intelligibility, improved choir and instrumental clarity, and expanded the recording capabilities, while minimizing the visual and physical impact on the historic building.
The new system achieved its goal of blending modern and advanced capabilities with flexible, but easy-to-use operation. By offering multiple modes of operation, the design allows Chapel staff to activate and use the system without navigating a complicated startup procedure. Additionally, the system has enough headroom to be used for a wide variety of events with no drop-off in quality or sonic clarity.
Special thanks to the Princeton Chapel staff and SIA Acoustics for being excellent partners and letting us be a part of this extraordinary project.
