Medium & Large Installation Problem Solving

When I was first called in to examine this church's existing system, one of the first things I noticed was the spider web of cables that had organically grown around and about the existing console. This would have been a nightmare to troubleshoot or trace! As far as performance was concerned, the existing main speakers were suffering from under powered amplifiers, blown compression horn drivers, and much of the power going to the existing Ev^® Subwoofers was being lost in a cable run in excess of 130 feet! No amount of bass boost could get those subs going. In addition to this, the sound was muffled, unclear, and had a pronounced and rather "honky" peak in the midrange that was difficult to listen to.

After speaking with the client about his existing equipment and the state it was in, and sensing that they were really looking for something new, I proposed a design using the existing Electrovoice mains and subs (after repairing the horn drivers, of course), all new CROWN^® power amplifiers, sidefill monitors by EAW^®, and an Allen Heath^® 24 channel console. His older yamaha stage monitors which were being used as sidefills were pressed into service as stage vocal monitors in this new configuration. All FOH equipment was to be housed in a RaXXess Elite^® series roll top desk. All wiring, including the electrical system, went through a radical overhaul.

All of the house electrical power for the system was redone in order to provide adequate power to the stage and FOH positions. The enire system, including the remote amplifiers and the musician's stage power is controlled from the FOH position by a sequencial power controller. Subwoofer and monitor amplifiers were moved from the balcony FOH position to a slide out rack assembly which slides into the stage platform, providing the absolute shortest cable runs to the subwoofers and monitors possible. This arrangement also alows easy access to the amplifier rack from both sides for system maintanance. Wall jacks with SPEAKON connectors were installed for the speaker cables to the monitors (previously speaker cables were simply poking out through holes cut in the stage), and a rack panel was mounted in the amplifier rack with sixteen Neutric XLR balanced connectors tied to the first sixteen channels of the house snake, which previously was buried under the platform in a location difficult to access. This is a very common mistake which usually leads to a multitude of microphone cables sprouting from holes in the unlikeliest of places, not to mention the fact that replacing a faulty microphone cable during a service becomes a nightmare.

NOTE: This was one installation where everything was so very wrong.

It was decided that the single crown amplifier running the main speakers would remain at the FOH position where it's predecessor lived since measurements indicated this would in fact yeald the shortest run to the speakers, unless I was willing to fly an amplifier rack up with the speakers and have electrical power run out to the location. As at this point such an installation would have been impractical for just one power amplifier, I chose to place it in the RaXXess Mixing desk.

All exposed cabling from the previous system was either run inside walls, or when not possible 2" X 2" wiremold raceway was installed into which the wire was placed. The inside of the RaXXess Elite^® series mixing desk made use of 2" X 2" slotted wireduct to organize and separate the power, speaker, and audio cables. Wiring at the slide out rack built into the stage was in like manner neatly organized and wire-tied. No loose cables exist anywhere that may be in the future tangled, strewn about, or pulled. Everything is strapped down and strain relieved.

Final testing of the system demonstrated a marked improvement in overall system volume, intellegibility, and gain before feedback. The customer was particularly satisfied in the marked increase in the subwoofer's performance, were previously most the amplifier power was being dropped accross the speaker cable runs from the balcony. When first firing up the system after tuning the room flat from 40hz - 20KHZ, we found that some sections of the building structure (particularly a hallway below the balcony) where actually vibrating so badly that I decided to tone down the sub output below 80HZ. Some other minor adjustments and the system was ready to roll!

NOTE: The client was very happy to see this mess gone!

The most dramatic and noticable change other than the sound itself is the overall appearance of the FOH area, which previously resembled a large cotton ball woven from microphone cables. It is now clean, organized, and the console and all equipment is housed in a cabinet that locks and provides both protection from dust and the environment as well as security.

The placement of speaker panel jacks, and the availability of sixteen of the console's twenty four channels at the amplifier rack have considerably cleaned up the front area as well. All microphone cables going to the drumset and for percusion instruments occupy mixer channels 17-24. Gone are the speaker and microphone cables sprouting from holes and the microphone cables that were actually being squeezed out from under the platform through the narrow space between the subwoofer cabinets and the platform front, all of which would have made the replacement of a bad microphone cable, or the re-assigning of a channel a near impossibility during a service or other event.

NOTE: Not very appealing, is it?

A great deal of the new installation's design took into account the client's future plans to expand to a two console system for front stage monitor mixing. Additional power amplifier channels and wiring are already in place, as well as two additional speaker jacks for monitors.

The future plans for expansion will add 2 additional monitor channels (for a total of four) running EAW cabinets as well. Four new headphone mixes (for a total of five) will be available for in ear monitors or headphones. All in all, including the sidefills, the system will then have a total of nine monitor channels, which should be enough even for the most demanding concert events! Since most of the work for this was designed into this new system, the cost of upgrading is kept to a minimum.

We often take the time to discuss the client's future plans and attempt to incorporate them in this manner into the overall design if it is at all possible. Such time spent thinking and planning ahead avoids the nightmares of having to tear new holes into walls after the fact to run new cables, or of having to replace large parts of the sound system in order to accomodate a rather simple change or upgrade.

The installation itself was scheduled around the church's calander so as to provide as minimal a disruption as possible to their regularly scheduled events, and concluded in a two day workshop to introduce the house technical staff to the new console and other equipment. Both of these are standard practice with all of our mid to large sized jobs. AMS SYSTEMS strives to keep the customer satisfied throughout the installation, as well as long after.

Iglesia De Cristo Misionera Gates Ave/Brooklyn Rev. David Aldorado.