Las Vegas, NV (November 13, 2006)–No matter what type of venue it may reside in, a sound reinforcement system simply isn’t “complete” until such time as it’s been tuned. The changes resulting from proper signal alignment, gain structure, and frequency shading of line arrays, for example, can have a dramatic impact on the intelligibility of dialogue, imaging, and numerous additional aspects of a SR system’s performance. Independent system tuner/acoustician Josh Evans has found success with a wireless approach–based around a rig from Lectrosonics–and has made significant contributions to the Las Vegas Hilton’s Hilton Theatre–currently home to Barry Manilow.
Josh Evans works on his SmaartLive 5 system in Las Vegas, NV.Evans, in addition to his work as a system tuner, is also an instructor for SIA Software’s Smaart FFT-based audio measurement software. While conducting a Smaart class at the Las Vegas Hilton, he had the opportunity to use the Hilton Theatre as a training venue. The theater, with roughly 2,300 seats and both under and over balcony seating areas, generates revenue of roughly $1M per week and has been host to many of Las Vegas’ most esteemed performers, including Elvis Presley.
Among the challenges Evans encountered at the venue was the issue of line array to subwoofer optimization. The system had previously been tuned using a laser range finder, which works by sending a laser pulse in a narrow beam towards an object and measuring the time taken by the pulse to be reflected off the target and returned to the sender. This technique only accounts for the physical offset and not the electro-acoustical offset of the array.
“In optimizing the relationship of the full range loudspeakers to the sub bass system,” said Evans, “we used an Earthworks M30BX precision measurement microphone with a Lectrosonics TM400 wireless system for test and measurement feeding into SmaartLive 5 running on my laptop computer. With the wireless system, we were able to freely walk the entire venue and take more measurements. The most significant benefit was being able to take spectrograph measurements over the entire audience area. This technique is extremely useful for displaying pre- and post-optimization of the system. Upon completion, we achieved approximately 6 dB of additional gain at the acoustical crossover region of the subwoofers by making changes to the signal delay settings.”
Evans was quick to point out the advantages of his wireless system, “Having the transmitter directly connected to microphone instead of having an unwieldy interface cable to drag around is huge,” said Evans. “The TM400 eliminates the compandor circuit commonly found in wireless systems, with the result being considerably more useable dynamic range and, hence, accurate measurements. By not being burdened with the cable, the tuning process is streamlined considerably and it’s not a problem to take all the measurements you need.”
The freedom of movement facilitated by wireless test and measurement tools is having a profound impact on the accuracy of SR system tuning, and Evans believes the cables can finally be left behind. “Wireless test and measurement systems like the TM400 are not only viable,” states Evans, “they really are the right solution to the complexities of system measurement. Their time has arrived.”