January 16, 2019

Sky’s The Limit

Choosing a ceiling design that doesn’t destroy a theater’s acoustics

When creating private theater rooms, many designers and architects now  understand the need for acoustical treatments in walls and that we don’t want large windows along side walls.  However, many popular architectural or interior treatments for ceilings can be problematic.

“We want a plain painted ceiling” is frequently the request by clients and designers that want a ceiling with no acoustical treatment and simple flat, smooth painted surface.  Either there is a concern about the budget or it is truly a design choice.  Whatever the reason, we want to be able to support our requirement to treat the ceiling and also offer an acceptable design alternative, if we expect to overcome these objections.  To support our design specification, we need to demonstrate validity. This is why it is essential to perform appropriate and accurate acoustical analysis that illustrates the difference between a treated and untreated ceiling.

Many designers and even clients may object to the seams which would generally be evident in even a stretch fabric system. But, if budget is not as great a concern, there are acoustical plaster solutions that, when properly specified and configured, can offer excellent balanced acoustical performance while visually maintaining a level five surface. If budget is a concern, several companies offer wide span fabrics that can deliver an acoustically correct ceiling with a seamless, architectural look.

 

The business of designing private theaters encompasses a mix of technical knowledge and aesthetic skills. On one hand we are creating a functional environment for the purpose of supporting the best audio, video and entertainment performance possible. We are engineering acoustical, audio, imaging, environmental and other sub-systems into a compatible assembly that is optimized for each room. On the other we are called to create a room where people will want to spend a lot of time and enjoy being inside. The greatest challenge is performing both skills expertly.

Frequently our skillset is stretched when we are tasked with making someone else’s idea work. This scenario frequently comes into play in dealing with ceilings in private theaters. It seems many understand the need for acoustical treatments in walls and even a better understanding that, no, we don’t want large windows on the side walls. However many popular architectural or interior treatments for ceilings can be problematic. Let’s take a look at a few typical scenarios and how to deal with them.

This analysis should be based on valid acoustical methodology and result in clearly understandable documentation so the client can clearly understand the difference in the two experiences. This type of professionalism can be very effective in overcoming either budgetary or design objections.

In the above scenario, it is still possible that, although the need for acoustical treatment is clear, the aesthetic objection is still strong.

Home Sweet Dome
Domes are exciting architectural elements.  Architects and designers love them. The problem is that domes introduce a significant acoustical distortion called focusing.  The simple solution is to demand that the dome be removed, but where would be the fun and challenge in that?

A well designed dome ceiling can add a sense of space, drama and excitement to a room, but it can also introduce a significant acoustical distortion called focusing.  The concave surface serves to reflect certain frequencies and harmonics to a specific location causing listeners to hear a horribly altered sound at those locations.  Depending on the dome shape, size and placement this can be a greatly or moderately destructive element.

The solutions for overcoming the negative effects of domes is similar, albeit more complex than our first example. Initially we must perform acoustical modeling to accurately predict where the problems will occur. With that knowledge we can engineer the correct configuration of acoustical & aesthetic solutions to resolve the problem.  Next we must look at the aesthetic and budgetary considerations. If a smooth-painted or even faux-painted or mural ceiling is required, the acoustical plaster products are a necessity. Be aware that the way these surfaces are painted (for the faux and mural applications) can destroy the acoustical performance.  Often a stretch fabric system can provide a more cost effective solution, however, due to the curved characteristic there will necessarily be seams, and/or sections of some sort to allow the fabric system to conform to the curve. Remember that integrating a balanced acoustical specification in a domed application will require significant engineering, design integration support as well as ongoing project support.

“We want a night-time sky”.
Fiber optic “starfield” ceilings are popular home theater details. These days, with LED lights and some other recent improvements have made these ceilings much simpler to integrate and capable of offering correct acoustical performance. Nonetheless, it is vital to analyze carefully what is being done to assure optimized results.

It is important to make sure the LED light sources are properly configured and include dimmable and controllable LED light engines to prevent improper light for video performance. The most vital consideration, and the one we most often see improperly specified, is the acoustical characteristic of these ceilings.  Many starfield ceiling products are 1” fiberglass panels with the fiber optics embedded. A common scenario is an entire cove ceiling treated with such a product. This would represent approximately 3 times the amount of acoustical treatment that would be appropriate for the surface area and at a very limited bandwidth performance. The end result would be a significantly imbalanced sound field.

The good news is that the same starfield can be produced with a stretch fabric application which allows a varied and acoustically correct acoustical treatment in the ceiling area. Again, remember to specify the correct acoustical treatments, validated by documented acoustical studies to assure the proper placement. Next, the installation should be performed by a qualified installer.

We often hear the term “no compromise” in relation to high performance. Sometimes we see these same “no compromise” systems placed in compromising positions due to aesthetic elements that do not support optimum performance. By providing valid analysis and utilizing our skill and creativity to look for aesthetic solutions that will not detract from performance, we can truly say that the “sky is the limit” in simultaneously delivering high performance and aesthetics.