The mono vs. stereo live sound debate went on for decades. For a long time, the mono approach prevailed. Considering costs, acoustics, equipment limitations, and so on, mono made sense. Incorporating stereo into a sound system added so many complications and compromises that it simply wasn’t considered practical. Mono worked.
Typically, most worship pastors and audio engineers will agree that the overriding priority for a church sound system is to provide intelligible coverage. That can be a huge challenge in itself, even with a mono sound system. However, today’s technology takes us into new, accessible, and affordable territory, including stereo — and beyond.
Utilizing stereo in your FOH sound is not a one-size-fits-all easy button for great sound. Even so, for many churches where the quality of music is a high value, stereo is essential. As we take a closer look at some of your available options, explanations may get a bit geeky. But here’s the takeaway: stereo can add engaging depth for many of your congregants, but the approach is not practical for every church. Let’s dive in.
- Terminology
- Clarifying Priorities
- Broadcast and In-ear Factors
- Know the Challenges
- Understand the Solutions
- What Do the Experts Say?
Terminology
Mono: Sound coming from a single channel. A channel is the sound console’s main output that feeds a center cluster, side, or fill speakers.
Left/Right (LR): A two-channel stereo system in which both the left and right channel are heard everywhere in the room.
Left/Center/Right (LCR): A three-channel system with most instruments placed in the stereo field (left/right) and primary instruments (main vocal, bass drum, bass guitar, snare drum, and presenter mic) located in either a phantom or an actual center channel. In recording, LCR sometimes refers to an older approach in which each individual instrument is heard exclusively in the left, center, or right channel.
Left/right/Center/left/Right (LrClR): Variants with multiple stereo fields covering different areas of the room, usually including a common center field that covers the entire room.
Immersive: Dolby Atmos for live sound, anyone? Check out the developments in L-Acoustics’ L-ISA, Meyer Sound’s Spacemap Go, and d&b audiotechnik’s Soundscape. It’s a brave, new world!
Clarifying Priorities
If you’ve read much of what I’ve written over the years to help churches move forward with their worship programs, then you’ll recognize the importance of identifying your specific goals when evaluating options. Exploring stereo is no exception.
Every church can evaluate itself in regard to these values and factors:
- Required level of intelligibility of the message
- Importance of creating engaging musical experiences
- Option-impacting acoustic factors (e.g., room shape and sound treatment)
- Current equipment and budgetary factors
- Technical ability of audio technician(s) and musicians
Each of these considerations gives shape to your options. For example, if your musicians have difficulty blending their parts well and the technical ability of your audio technician is limited, then you may be more successful by focusing on a simplified mono sound system. Likewise, covering a wide, shallow, and reflective auditorium involves tricky acoustic issues that are only complicated by employing stereo.
Discussing these factors with your Sweetwater Sales Engineer may clarify what options are available to help you reach the solution to accomplish your specific goal.
Broadcast and In-ear Factors
As churches reconsider stereo, one related factor is the widespread use of stereo in broadcasting services and in-ear monitors. Every day, your congregants stream content on stereo devices at home, in the car, on their personal devices, and at work — modern ears expect stereo sound. Musicians are used to playing and hearing their guitar pedal platforms and keyboards in stereo and may play less confidently when running mono. Because of these factors, even churches that use mono auditorium sound systems record some instruments and room mics in stereo.
Because many of today’s church sound systems are capable of handling stereo channels, incorporating some stereo elements into your front-of-house sound may not be as much of a stretch as you may have thought. It’s a tempting possibility!
Know the Challenges
Running mono sound means that there’s only one signal being fed into the room. While that sounds simple, providing even, intelligible coverage may require multiple primary and fill speakers. There’s less equipment and wiring than in a stereo system. Even so, phasing, comb filtering, and acoustic treatment must be addressed.
Adding stereo channels increases the complexity. Now there are two separate channels that must be clearly heard by everyone in the room. The potential for comb filtering increases, too.
Plus, it’s not just a matter of hearing the different signals with even coverage. It matters when your ears hear each of the signals. The farther a person is from a speaker source, the more the high frequencies drop off and the quieter that signal seems to be. That’s why the closer a person is to the left speaker than the right, the more dominant everything becomes in the left channel, even if they’re the same level. The balance of the mix will shift significantly based on where a person is located in the room.
Understand the Solutions
Every approach offers benefits and challenges. Thankfully, current technology and techniques have progressed to the point where running a form of stereo is far less of a compromise.
Onboard DSP in speakers, crossovers, consoles, and outboard gear helps align the timing of signals. Modern acoustic treatment minimizes the effects of reverberation. Speakers can be selected for specific field angles to help control field bleed and minimize comb filtering. There are many options available that will allow most auditoriums to gain the benefits of stereo while also minimizing the muddying problems.
Instruments can help, as well. Most sound consoles allow the audio engineer to roll off the low frequencies in most instruments, which removes unnecessary sound that muddies the overall stereo image, as well as to adjust EQ separately on each channel to minimize phase issues. Similarly, some keyboards and guitar pedal platforms allow the musician to create separate sound structures for both the left and right outputs.
For example, I replicate an LCR approach on my Helix guitar pedal by routing a mono (center) dry amp/cab signal separately from the wet stereo effects. While I could send separate left, right, and center channels to the console, I’ve found that left and right outputs with a phantom center is adequate for FOH and my in-ears. This combo creates a gooey outside and a chewy center, offering both the clarity to cut through a mix and the ambience to create a wide, full sense of space.
Likewise, audio engineers have learned to pan responsibly. Primary instruments, including the main vocal, bass drum, bass guitar, snare drum, and presenter mic, are panned to the stereo phantom center. Other instruments are panned gently right and left, no more than ±30%, and ambient sounds are panned wider for effect. This creates a stereo-like sense of width while minimizing the variance in mix blend due to seat location. Individual mono instruments can be doubled and separate signals EQed and time delayed so that the distinct right and left feeds are present while avoiding comb-filtering issues.
Many churches increase the intelligibility of their stereo sound by adding an actual (not phantom) center channel. Primary instruments (main vocal, bass drum, bass guitar, snare drum, and presenter mic) are placed here rather than in the stereo channels. Just like each of the stereo channels, this third channel must be heard by everyone in the room.
Designing stereo and LCR systems can be tricky. Each channel typically uses a combination of primary speakers and fills to adequately cover the full space evenly without causing phase cancellation. But modeling technology and insight from the pros can help make designing a great stereo system possible.
What Do the Experts Say?
I reached out to three Sweetwater Integration experts who deal with stereo (and beyond) systems every day. While their experience has come from shaping the sound of huge churches including Bethel Music, Hillsong, Saddleback, and Willow Creek, they’ve also worked with many medium and smaller churches to create high-impact sound systems. Here’s what they had to say.
Aaron Ruse
Technical director at Saddleback Church and audio engineer at Willow Creek Community Church
Stereo is common at most venues where music playback is involved. I can safely approach design with the assumption that at least 60%–70% of the listeners can benefit from a stereo experience in most rooms. Allowing for stereo inputs and bussing is a super-important factor. Fills are usually a sum mono or a reverse of the main speaker, and subs are mono. With multiple cabinet arrays, many options now exist to create directional patterns.
The art of live mixing includes panning. Extremely wide panning is typically avoided in live mixes. Panning closer to center also makes it easier to blend instruments or protect weaker musicians. Panning something wide can make it stand out or become distracting.
Among progressive churches, I’m finding that we’ve moved beyond the mono vs. stereo conversation. We’re now talking about immersive audio. Think of the benefits of bringing surround sound to large-scale worship centers. Advanced DSP is making this more successful than ever before — both in how widely the audience is impacted and how intuitive the system is for the mix engineer to access. Many top manufacturers are now offering immersive solutions.
Proper system design is a sophisticated process involving high-level design theory and real-world experience. Predictive modeling helps ensure that designs will perform as needed within the space.
Kevin Watson
Director of design services with All Pro Integrated Systems/Sweetwater Integration
When I’m modeling a system, the room has a huge impact on loudspeaker design and how practical stereo and mono approaches can be. Many churches want to mix in stereo. Some room shapes limit coverage, but even partial stereo can be beneficial when there is similar loudness coverage to everyone from the left and right speaker locations.
Regarding panning, the mix shouldn’t be hard-panned right or left — some listeners won’t hear any of the signal from the other side due to their position. I like to pan from the listener’s perspective so that what they hear lines up with what they see. When seated on an extreme side, all the instruments come from the stage, and the sound should, too. For those seats, panning misplaces the aural image. That’s one reason why a center speaker location is nice when you listen to someone who is on the center of the platform, such as during a sermon. Their voice matches their physical location.
When determining the right solution for a venue, it’s also important to consider nontechnical factors including budget and volunteer experience.
Clint Aull
Production manager at Bethel Church, FOH engineer at Hillsong Worship, and production manager with For King and Country
When I discuss mono vs. LCR vs. stereo vs. immersive, my number one question is, “What is the source content?” Properly matching the source content will best achieve the intent of the content. That’s the determining factor.
Correctly converting one type of content into another can be problematic. Summing stereo source content into mono can create phase cancellation and degrade the content. The same is true when summing immersive to stereo. Trying to create LCR without actually separating the content into true LCR and removing that content from the left and right channels may create a far worse listening experience.
So, if you’re using MP3 or stereo playback, then stick with stereo and mix with panning to create space. Create the PA to match the source content.
Time to Give Stereo a Shot?
Any adjustment to your church audio system can be daunting. It’s worth taking seriously. Quality sound is vital to helping your congregation engage. Whether you are addressing current concerns or exploring adding some engaging aspects of stereo into your live or broadcast systems, Sweetwater’s experienced Sales Engineers can clarify your options. Plus, with our full access to the Sweetwater Integration experts, we can provide a complete array of solutions so that you can determine the best path that matches your goals. Reach out to us at (800) 222-4700 for personalized recommendations.