CHCC Remodel: New PA, Pt. 1

One of the biggest things I’m looking forward to in this renovation process is the new PA. For five years, this PA has been the bane of my FOH existence. Of the 12 speakers in the two clusters, 8 of them are pointed at walls. Only two actually cover the audience. As a result, 80% of our seating area is off-axis of the old PA. And with all that reflected energy coming back off the walls, it’s a less than clear system. 

Choosing a PA

I actually chose our PA well over a year ago. My friend Duke kept telling me about Bose RoomMatch and how he thought it would be a great solution in our room. After hearing it in several venues, we did a demo in our room. It was clear it would work great. 

Now I know some of you are scoffing at the name Bose. And if you haven’t heard the RoomMatch, you’re forgiven. Previous Bose systems were less than stellar. The new RoomMatch, however, has a lot going for it. It may not be an L’Acoustics or Meyer, but those are out of our price range. I looked hard and couldn’t find anything close to as good in our budget. And to be honest, RoomMatch is probably 80-85% the PA of the best of the best, and that’s good enough for 98% of the people in the seats. Getting another 10% in quality would cost almost 100% more, and that’s not worth it for this application.

And it really is going to sound good. Trust me. 

This was the final iteration of the first design. It was a 3-4-3 setup, and as you can see, pretty darn even between 1-4KHz.

This was the final iteration of the first design. It was a 3-4-3 setup, and as you can see, pretty darn even between 1-4KHz.

Choosing the Design

Initially, I really wanted to focus on speech intelligibility when we designed the PA. And that meant an exploded mono cluster. Many people mistakenly believed we were doing an LCR array, when in fact, each of the clusters were designed to cover one seating are with as little overlap as possible. While that would have made speech sound really, really good, the more I thought about it, the more I second-guessed myself on the music side. 

An exploded mono cluster has the advantage of delivering very consistent sound to each seat in the room. That’s a good thing. On the other hand, you can’t really do anything with panning to open up the frequency spectrum for vocals. In a busy mix, this can become challenging. 

Our original designs for the exploded mono system looked very good. As you can see from the above plot, we were ±0.9 dB between 2-4KHz over the entire seating area. That’s some even coverage. For reference, our current system is about ±9.0 dB. Yeah…

It's not quite as even, but I like the center coverage. 

It's not quite as even, but I like the center coverage. 

Going Stereo

OK, not really stereo. But over Christmas, I started really paying attention to my mix and how much I was using left and right. Our current system isn’t really stereo in the sense that it’s delivering a stereo image to the whole room—though there’s so much reflected sound, it actually might be. Still, I used that left-right design to create some cool ambience in the mix. 

By double patching and delaying the guitar, I could keep it out of the way of the vocals when I needed to. The B3 is stereo, as are keys and piano. Those sound really cool when I widen them out. Even the cymbals open up a bit when I pan them left and right some, and when we have a bunch of vocals, I spread them out across the sound field. 

You can see how far the house right cluster extends into the house left seating area. And coverage on the walls is still pretty minimal.

You can see how far the house right cluster extends into the house left seating area. And coverage on the walls is still pretty minimal.

So I went back to CCI and Bose and asked them to work up a left-right design for me. We went through about five iterations before we landed on one that we all liked.

One of the challenges was to keep the coverage off the thrust as it extends quite a bit further than our current one does. CCI worked really hard with positioning, angle and box selection to make sure we shouldn’t have any feedback issues. 

That’s part of the picture. Next time, we’ll delve into how we got there, talk about the low end, amplification and how we plan to deal with speech.

“Gear