Tech Feature

In this month’s tech column, we unpack the concept of reverberation, and the measurement known as RT60. Commonly bandied about by audio professionals, these terms are frequently misapplied or misunderstood. Often when we say reverberation, we mean discrete echoes. Leading into the discussion of reverberation, we will review some general acoustics concepts, and then apply those concepts to the dictionary definition of reverberation. Then we’ll talk practically about applying equalization, and the effect of volume on our perception of reverberation.

This issue of FRONT of HOUSE is focused around the house of worship market, an area where I have a large amount of personal experience. From volunteering at my own small church, to being a hired gun in large mega churches, the majority of my hours logged behind a mixing console have been in the church setting. As a result, I have direct experience in this area, which may make this article rather contrarian to what is usually composed regarding church sound.

Perhaps you are the owner of a regional production company, the sound guy for your band, or the production manager for a venue. Over the years you have purchased better microphones, switched from an analog console to a digital console, added a DSP to your system and maybe even moved to self-powered loudspeakers. Every once in a while, you’ve had a band mixer or system tech show up with SMAART, or Systune, or SpectraFoo to “tune your system.” Sometimes the results have been impressive, other times, not so much. Either way you see that said sound person has well over $1,000 invested in software, computers, microphones and interfaces to enable them to do whatever they’re doing, and you decided it is not worth the money for your business, band or venue.

Vertically arrayed speaker deployments increasingly rule the day in pro audio. Such systems have advantages in deployment, sightlines, and dividing the audience into different coverage zones. This month’s tech feature is the second in a series that will detail real-world complexities involved in deploying vertical arrays and practical approaches that the system technician can apply to ensure even coverage throughout the audience area.

From the summer festival setup on a Stageline SL100 mobile stage to shows at a “shed” amphitheater, to the largest arena productions, vertically arrayed speaker deployments increasingly rule the day in pro audio. Vertical arrays have advantages in deployment, sightlines, and dividing the audience into different coverage zones. Here in the pages of FRONT of HOUSE, I have talked about the physical principles of vertical arrays but not about their practical field deployment for the working technician. We will now remedy this situation, as this month’s tech feature is the first in a series that will detail some real-world idiosyncrasies involved in deploying vertical arrays and practical approaches that the system technician can apply to ensure even coverage throughout the audience area.

For this month’s technical column, we diverge from the more traditional topics of speakers, arrays, electronics, etc., to talk about a topic extremely important to the longevity of the pro audio industry, that of event safety.

If there was ever an area of constant activity and interest within the live audio community, the Federal Communication Commission’s proposed reallocation and plans for an upcoming auction of the 600 MHz UHF spectrum would surely head the list. Currently, the auction is scheduled for mid-2015. Meanwhile, well-heeled companies in the telecom industry — including AT&T, Verizon and Sprint — are anxious to pony up as much as an estimated $20 billion for that chunk of prime cyber real estate. And it’s a big-stakes game, with the winners set to take a commanding position in the burgeoning mobile device market.

Since the earliest days of professional audio, users have needed more output, coverage and frequency response than a single loudspeaker transducer could provide. Even with dramatic increases in modern transducer performance, it would seem that combining multiple drivers together, whether for response, coverage, or output will be a perpetual fixture of the industry. Because of the limitations of drivers, much of the effort in professional loudspeaker design has been expended in combining multiple drivers in a single loudspeaker box, and then combining multiple boxes together into arrays.

Horns of various sizes and shapes have been with us since the formative days of professional sound reinforcement. Whether stacked on top of a bass bin in the early days, or carefully integrated into the injection molded housing of a powered loudspeaker today, horns are here to stay.