ACOUSTICAL DESIGN IDEAS FOR A NEW TIME

In Uncategorizedby tfwm

Worship styles have changed. Even the most traditional styles of worship are integrating a significant amount of technology into their services. For established buildings, this greater use of technology is all too frequently at odds with the original architecture. A space that was properly designed for choir and organ is not going to respond well to drums and sound-reinforced “praise/worship” style services. This creates an opportunity for today’s a/v integrator to provide solutions. In terms of acoustics, there are two areas where an integrator should focus: the worship platform (singers and musicians) and the congregation itself.

Although the needs of the congregation may be the most important overall, the needs of the platform are the proper place to start. First, objectively look at the space in question: a space that was designed for a choir and organ will likely have hard and/or angled surfaces that both give the performers acoustical energy to enhance performance and propagate that energy pleasantly toward the congregation. The changes to higher SPL’s (Sound Pressure Levels) and more directional sound sources make these architectural features a detriment, not a benefit.

The purpose on the platform is to promote worship first and not just a slick performance. There are great advances in in-ear monitors, wireless mic and headphone systems, amp modules and electronic drums that can render the volume created on the platform almost non-existent. These technologies can solve acoustical issues that drums, amps and floor monitors create, but they may not allow the musicians and singers to properly create inspired music. Greater control does not result in better worship. The experience of the worship leader and musicians must relate to the technologies in use.

An interesting example of an application using real amps, real speakers and fewer headphones, is East Side Church of God in Anderson, Indiana. East Side is an established congregation with a great history of praise and worship. Many of the musicians are in fact studio and live players within the ministries of Bill Gaither and Sandi Patti. This history is actually part of the conflict, as the effectiveness of the monitoring and sound system relied on the vast amount of experience of the ministry. However, a new group of young players has emerged. The role of the experienced players has now become one of ‘trainers.’ The goal became to help the younger players to listen and play with “experienced ears.”

The praise band was previously located stage-left in a half pit situation. The drums were located in a custom-built enclosure with good visual communication but minimal sonic communication (dedicated “Q” mix). All of the other musicians monitored through floor wedges. The younger players were not experienced enough to play through these ‘barriers.’

A plan was developed to move the praise band dead center under the baptistery. This would split the choir into two sections. Half walls were constructed to “frame” the band, and side-located amp closets were included in the design to allow monitors and amps to fire directly at each player. The drums were removed from the enclosure and a small set of drum shields was placed in front of the set.

Step one accomplished… now what were the ramifications? Acoustically, they were significant. The existing architecture of the platform featured an angled “cloud” constructed of drywall that propagated the choir energy evenly toward the congregation. This cloud now became a source of intensely-focused reflections. The experience of a person sitting on the main floor verses a person sitting in the balcony was completely inconsistent. The Front-of-House engineer was now placed in a difficult situation.

To improve the situation, East Side Church of God worked with Auralex Acoustics to minimize the issues of the new room. Auralex Acoustics ProPanels were placed near the sound sources, including on the side walls and the rear area under the baptistery. To address the ceiling reflections, a series of 4’x4’x2” acoustical panels were hung as a ‘cloud’ below the existing drywall cloud and above the new pit area. The coverage was approximately 75% of the 16’x16’ pit area and the panels were located almost parallel to the platform.

Results:
Pastor Mick Gilliam, the worship leader, enjoys the ability to communicate freely with the musicians all at once, as opposed to making special cues to the previously isolated drummer and various sections of the praise band. They have also been able to conduct band seminars to teach this skill of listening to the “whole” band. This effort is not without obstacles as the drums can cause issues in the room if the player gets too aggressive. The point of this example is to showcase how a stage with physical sound energy moving through the air can be a viable way to lead worship when combined with a strategic use of acoustical materials.

Now, what about the needs of the congregation?

As stated earlier, this is where the space must fully come together; where technology must match acoustical features and result in a comfortable worship experience for every member. A space that was designed for traditional services is likely to experience two primary acoustical concerns: slapback reflections off the rear wall and flutter echoes between parallel side walls. Slapback reflections cause issues at the platform, primarily for the pastor who will hear very troubling reflections in a delayed manner. Even if this is not disturbing the congregation, it sometimes becomes the catalyst to solve other acoustical concerns. Flutter echoes result in slurred and uneven responses within the congregation. These are issues that a new PA system can not correct.

Beyond those two primary issues, the decay time of sound energy must work with a more aggressive style of worship that is reliant on the PA rather than room reinforcement. Technically the acoustical criterion is RT60— the time, in seconds, it takes for a 500 Hz sound source to decay 60 dB. In basic terms, a contemporary worship space should be somewhere in the range of a 1.5 second RT60.

Next, the frequency curve of the space should be analyzed. Some spaces will have excessive lower frequency issues. Most consonants in speech are in the higher frequencies, making it imperative to address excessive “lows” that could possibly mask good speech intelligibility. Other spaces may have exposed mid-range resonance resulting in a very harsh sounding space. By properly analyzing this data, it becomes possible to place the appropriate types and amounts of acoustical materials, be they acoustical absorbers or acoustical diffusers.

To better highlight this concept of retro-fitting acoustics to a changed worship style, we can look at Grace Presbyterian in Kernersville, North Carolina. Grace Presbyterian has a congregation of 300. Although the space was recently constructed, it was designed for a service that used the chorus and organ. In early 2004, the church made the decision to switch from a traditional to a contemporary service, replacing chorus and organ-based music with a praise band.

The problems became apparent shortly after the transition when parishioners began noticing high levels of reverberation, or, echoes during band performances. The reverberation caused the music to sound garbled and the lyrics inaudible. Not surprisingly, the problem was initially attributed to an insufficient sound system.

The shape of Grace’s sanctuary is octagonal. Sound from the band’s performance was hitting all sides of the walls and ceiling and effectively bouncing around the sanctuary, echoing through the chamber. While the ideal Reverberation Time (RT60) for this space should be 1.5 seconds @ 500 Hz based on its function, Grace’s predicted RT60 was three to four seconds. Another factor affecting the acoustical design was the excessive low frequency issue previously mentioned.

The resulting solution was to install 1,364 square feet of absorptive treatment using 2” thick Auralex ProPanels. The placement of these panels on upper portions of specific wall surfaces and areas of the ceiling was designed to enhance speech intelligibility and promote an evenly distributed worship presentation.

The treatments helped the church complete its transition to a contemporary style of worship. In the same manner that they spoke of “sonic chaos” before the acoustics were installed, the parishioners now noted the vast improvement in the sound of the sanctuary, allowing them to enjoy the praise band. As an added bonus, the members also offered pleasing comments on the architectural panel design and its aesthetic appeal.

Summary:
We are in a new time for worship presentation. It is now the combined burden of A/V integrators, technical ministers and worship leaders to lead the transition of these new worship styles to spaces that may not be designed for such functions. The key to a successful integration involves an understanding of the existing architecture, the use of the latest technology, and the joining of the two together with a properly designed acoustical treatment plan. There are many great resources available to help with such a plan, including the use of acoustical consultants from the National Council of Acoustical Consultants (www.NCAC.com), acoustical design firms such as Russ Berger Design Group (www.RBDG.com), and many of the acoustical material manufacturers. With the proper preparation and research, any facility can be renovated to accommodate the unique dynamics of your desired worship style.