🎚️ Issue #9: The Glossary You Need to Survive (and Thrive) -- Part 5

THIS WEEK’S SETLIST

What You’ll Learn Today

• Surgical vs. Musical EQ: Discover how the ‘Q’ (or Width) knob is your secret weapon for either killing a precise feedback note or gently shaping an instrument's tone.

• Why Your Room Fights Your Mix: Learn how your church's Room Acoustics and its boomy Room Modes are the hidden source of many of your most frustrating EQ and feedback problems.

• Solve Problems Like a Pro: Understand your Signal Chain to create a mental map of your system, helping you find and fix issues in seconds instead of randomly checking cables.

Just for today… (more coming next week)

41. Psychoacoustics

42. Q (Quality Factor / Bandwidth in EQ)

43. Room Acoustics

44. Room Modes

45. Signal Chain / Signal Flow

👋 WELCOME

BUILT FOR VOLUNTEERS IN THE BOOTH

Every week in SundayMix, you’ll get no-fluff FOH tactics to help you run tighter, cleaner, more confident worship mixes — even when service starts in five and chaos is in the air.

Let’s be real — no one’s probably showing you how to do this. You’re in the booth because you said yes… and now Sunday’s coming.

Let me know what you need most. Got a topic you’re struggling with behind the board? Hit reply and tell me. We read every response — and I’ll build future issues to solve it.

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Excessive Swelling? Do THIS Daily

Hi friend,

You know what happens when a toilet gets backed up…

It overflows. It smells. It's a mess.

Now imagine something just like that happening inside your body.

Every day. Quietly. Constantly.

❌ The heaviness in your legs.

❌ The swelling in your ankles.

❌ That stiff, bloated feeling you can't shake.

Turns out, there's a hidden "drainage pipe" inside you that may be backing up.

And when it does, it floods your lower body with fluid and waste.

(No, this has nothing to do with your heart, salt intake, or blood pressure.)

Most people have never even heard of it.

And outdated doctors diagnosed it wrong.

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And it could transform the way your legs feel — starting today.

SUNDAYMIX READER SPOTLIGHT

That phantom buzz is a classic and frustrating problem! It's rarely the musician's fault. The key is to remember that even if your audio gear is the same, the electrical environment changes on Sunday morning when all the lights, projectors, and other systems are fully powered on.

Here’s a quick, systematic plan to find the source.

1. Isolate the Source (On Stage)

• Turn the instrument's volume knob all the way down.

  • Buzz Gone? The problem is likely in the instrument's electronics or shielding.

  • Buzz Remains? The issue is in the cable, DI box, or power path.

• If it's the instrument: Does turning your body change the buzz? You're picking up interference (likely from lights). Does touching the metal strings make it quieter? It's probably a shielding issue inside the bass.

2. Check the Signal Path

• Bypass all effect pedals. Plug the instrument directly into the DI box. If the buzz disappears, add pedals back one by one to find the noisy culprit (check its power supply!).

• Swap components. Try a different instrument cable, a different XLR cable, and a different DI box to rule them out.

3. Hunt for the "Sunday Morning" Problem

• Lighting is the #1 suspect. During a quiet setup time, have someone bring the lights up to full Sunday-morning levels. If the buzz appears, you've found the source. Try to plug your audio gear into outlets on a separate electrical circuit from the lighting dimmers.

• Check for shared circuits. What else is on? Projectors, coffee makers, or kitchen appliances can add noise if they share a circuit with your stage power.

Quick Fixes "In the Moment"

• For the Musician: If the buzz changes with your position, simply turning your body can often find a "null" spot that reduces the interference.

• For the Sound Tech: Use a very narrow EQ cut (a "notch filter") to surgically remove the specific buzz frequency (usually 60Hz and its harmonics like 120Hz). As a last resort, a noise gate can hide the buzz when the instrument isn't playing.

The Solution: Work with your sound tech to go through these steps systematically during a non-service time. You can solve this!

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How To Drain Lymph Fluid In Ankles And Legs? (Try This)

Tired of excessive swelling holding you back from the activities you love?

Studies show this new approach might help you get a long awaited relief from swollen legs and feet.

And it doesn't involve compression stockings, elevating your legs, or cutting out salt.

Ready to ease that heavy, swollen feeling?

Watch this video to find out how

41. Psychoacoustics

• In Plain English and How to Use It: This is the study of how we humans actually hear and perceive sound – it's not just what the microphones pick up, but how our brains interpret it. For example, the Haas Effect (how we tell where sound is coming from based on what arrives first) is a psychoacoustic thing.
  

  • How to Use It: Understanding a bit about psychoacoustics helps FOH engineers make mixes that not only sound technically good but also feel right and connect emotionally with the audience. It influences decisions about panning (stereo placement), reverb, delays, and overall tonal balance to create a pleasing and immersive experience.

• Advanced but Still Usable: Psychoacoustics is the branch of psychophysics involving the scientific study of sound perception and audiology—how humans perceive various sounds. It explores the psychological and physiological responses associated with sound (including speech and music). Key concepts include loudness perception (Equal Loudness Contours like Fletcher-Munson), pitch perception, timbre, spatial localization (interaural time differences, interaural level differences, Haas effect), masking effects, and the perception of distortion and noise. Elite FOH engineers leverage psychoacoustic principles to create mixes that are not only technically proficient but also perceptually optimized for clarity, impact, and emotional engagement within the context of human hearing.

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Swollen Feet & Ankles? Try THIS And See How It Feels (Watch Now)

Want to get long-lasting relief from your excessive swelling?

According to dozens of studies, this tropical cooler has three powerful heaviness-busters that might kick your painfull swelling to the curb.

If you’re fed up with heavy legs and feet…

Then you need to see this video now

42. Q (Quality Factor / Bandwidth in EQ)

• In Plain English and How to Use It: When you're using an EQ that lets you pick a specific sound (frequency) to adjust (like on a parametric EQ), the "Q" setting controls how wide or narrow that adjustment is.
  

  • Low Q = Wide: Affects a broad range of sounds around the one you picked. Good for gentle, overall tone shaping.

  • High Q = Narrow: Affects only a very small, specific range of sounds. Good for surgically cutting out a problem like feedback or a single annoying ringing note, without messing up the sounds nearby.

  • How to Use It: Use a wider Q for general sweetening (like adding a bit of "air" to vocals). Use a narrower Q for fixing problems (like cutting a "honky" frequency in a guitar or notching out feedback).

• Advanced but Still Usable: In equalization, Q (Quality Factor) is a parameter that defines the bandwidth of a bell-shaped (peaking or dipping) filter, such as those found in parametric EQs. It is inversely related to bandwidth:
  

  • A high Q value results in a narrow bandwidth, meaning the filter affects a very selective range of frequencies. This is used for surgical adjustments like notch filtering feedback or attenuating specific resonances.

  • A low Q value results in a wide bandwidth, meaning the filter affects a broader range of frequencies. This is used for general tonal shaping, like gentle boosts for warmth or presence. Mathematically, for a peaking filter, Q can be defined as Q=fc​/BW, where fc​ is the center frequency and BW is the bandwidth (the difference between the upper and lower frequencies at which the filter's response is -3 dB relative to the peak gain).

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Excessive Swelling? Do THIS Daily

Want to achieve long-lasting relief from your excessive swelling?

According to dozens of studies, this tropical cooler has three powerful heaviness-busters that might kick your painful swelling to the curb. 

If you're fed up with heavy legs and feet…

>> Then you need to see this video!

43. Room Acoustics

• In Plain English and How to Use It: This refers to how sound behaves in a particular room – how it bounces off walls, ceilings, and floors, or gets absorbed by things like curtains, carpets, or people. Every room sounds different! Some rooms are very "live" or "echoey," while others are "dead" or "dry."
  

  • How to Use It: The room's acoustics have a HUGE impact on your mix. A bad-sounding room can make even the best PA system sound muddy, unclear, or prone to feedback.

    • Walk the room and listen for weird dead spots, boomy areas, or annoying echoes.

    • If the room is very reflective, you might need to mix "drier" (less reverb/delay effects).

    • Adding acoustic treatment can drastically improve room acoustics.

• Advanced but Still Usable: Room acoustics describes the behavior of sound waves within an enclosed space, including phenomena like reflection, absorption, diffusion, diffraction, and reverberation. Key acoustic parameters include:
  

  • Reverberation Time (RT60​): The time it takes for sound energy to decay by 60 dB after the source stops.

  • Early Reflections: Discrete reflections arriving shortly after the direct sound, significantly impacting clarity and timbre.

  • Standing Waves (Room Modes): Resonances at frequencies determined by room dimensions, causing uneven bass response.

  • Speech Transmission Index (STI) / Speech Intelligibility (SI): Measures of clarity for spoken word. The acoustic characteristics of a venue profoundly affect the perceived sound quality of a reinforced system. FOH engineers must adapt their mixing approach to the room, and in ideal scenarios, the room is treated acoustically to provide a more controlled and favorable environment for both reinforced and unreinforced sound.

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44. Room Modes

• In Plain English and How to Use It: In any room, certain bass frequencies will sound much louder or "boomier" than others, or some will seem to disappear in certain spots. These are caused by "room modes," which are like sound waves getting trapped and building up between the walls, floor, and ceiling because of the room's specific dimensions.
  

  • How to Use It: If you notice very uneven bass in your room (some notes are way too loud, others are weak), it's likely due to room modes.

    • Try moving your subwoofers to different locations (this can make a big difference).

    • Careful EQ on the PA system (often a narrow cut at the problem bass frequency) can help, but it's tricky.

    • Acoustic treatment designed for low frequencies (bass traps) is the most effective solution but is often a bigger project.

• Advanced but Still Usable: Room modes (or standing waves) are natural acoustic resonances that occur in an enclosed space when sound waves reflect between parallel surfaces (walls, floor, ceiling), reinforcing or canceling each other at specific frequencies determined by the room's dimensions.
  

  • Axial modes: Occur between two parallel surfaces.

  • Tangential modes: Occur between four surfaces.

  • Oblique modes: Occur between six surfaces. Axial modes are typically the most prominent. These modes result in an uneven low-frequency response within the room, with audible peaks (areas of high SPL) and nulls (areas of low SPL) at the modal frequencies. Treatment involves strategic placement of subwoofers, listener positioning, careful system EQ (though EQ cannot fix nulls everywhere), and the use of low-frequency absorption (bass traps). The frequencies of axial modes can be calculated as f=nc/2L, where L is the room dimension, c is the speed of sound, and n is an integer (1, 2, 3,...).

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That Persistent Puffiness… What Is Your Body Trying to Tell You?

You know the feeling. The day ends, you kick off your shoes, and there it is: a stubborn puffiness in your feet and ankles that won’t seem to go away. Your rings feel tighter, your joints ache, and a frustrating feeling of heaviness sets in. You’ve blamed gravity, salty foods, or just a long day on your feet. But what if the real culprit is a hidden system within your own body, silently crying out for help?

Most of us have never given a second thought to one of our most vital networks: the lymphatic system. It’s your body's silent, built-in purification plant, a complex web of vessels and nodes tasked with draining excess fluid, filtering out waste, and keeping your internal environment clean. When this system becomes sluggish or overwhelmed, the drainage slows to a trickle. The result? That mysterious and uncomfortable swelling, known medically as edema or lymphedema, that you can’t seem to solve.

The clues are often subtle at first. But what if you could learn to read them? And what if the secret to fighting back against this fluid buildup isn't a mystery after all?

Unlocking Nature’s Secrets for Fluid Balance

While it's essential to decode your body's signals with a healthcare professional, a growing field of interest lies in supporting this forgotten system. Lymph support supplements contain specific natural compounds, some of which have been used for centuries, that are now being investigated for their remarkable effects.

• The Herbal Enigmas: Did you know a common backyard "weed" could hold a key? Dandelion has long been studied for its natural diuretic abilities, potentially helping your body release trapped water. Other herbs like red clover and calendula are traditionally seen as lymphatic "movers," believed to nudge the system back into a healthy flow.

• The Power of Bioflavonoids: What if part of the secret was hidden inside the peel of an orange? Citrus-derived compounds like diosmin and hesperidin have been clinically researched for their ability to improve the tone and health of the body's tiniest vessels. Studies suggest these powerful flavonoids can help reduce the feeling of heaviness and swelling in the legs. Similarly, horse chestnut extract is another well-researched botanical key to unlocking better circulation and easing swelling.

• Essential Mineral Codes: A trace mineral, selenium, has also emerged as a subject of scientific curiosity. Early studies suggest it may play a unique role in reducing lymphedema, possibly by deploying its antioxidant and anti-inflammatory properties to protect the delicate lymphatic channels.

You’ve now uncovered a major clue in your investigation into persistent puffiness. But understanding the problem is only the beginning.

What if the key to truly reducing your swelling wasn't just in a supplement, but in a simple 5-minute routine you're likely overlooking? We're revealing exactly what that is later this week.

Furthermore, solving this issue is about having all the right tools. And soon, we’re making it much easier for you to get them. Keep a close watch this Thursday, as we'll be unlocking an exclusive opportunity for our readers to finally take action.

Click here to learn more

45. Signal Chain / Signal Flow

• In Plain English and How to Use It: This is the path your audio signal takes from the very beginning (like the microphone) all the way to the very end (the speakers), going through all the different pieces of equipment in between (preamp, EQ, compressor, fader, effects, amplifiers, etc.).
  

  • How to Use It: Understanding your signal chain is crucial for troubleshooting. If you're not getting sound, or the sound is bad, you can mentally (or by looking at your mixer's block diagram) trace the signal path step-by-step to find out where the problem is. It also helps you understand how different processors (like EQ before a compressor vs. after) will affect each other.

• Advanced but Still Usable: Signal chain (or signal flow) refers to the sequence of audio devices or processing stages through which an audio signal passes from its source to its destination. In a typical mixing console channel, this might be: Microphone → Preamp → Insert (for external processors) → EQ → Dynamics (Compressor/Gate) → Fader → Pan → Bus Assigns → Master Output. Understanding the signal flow is fundamental for:
  

  • Troubleshooting: Identifying where a signal is lost or degraded.

  • Processing Order: Knowing how the order of processors (e.g., EQ before or after compression) affects the outcome.

  • Gain Staging: Managing levels effectively at each point in the chain. Modern digital consoles often offer flexible signal flow, allowing users to reorder processing blocks.

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SUNDAYMIX ACTION STEPS

3 THINGS TO IMPLEMENT THIS NEWSLETTER TODAY

1. Build Your "Why it Sounds That Way" Vocabulary.

• Action: This week, focus on three foundational concepts: Q (Quality Factor) (#42), Room Acoustics (#43), and Signal Chain (#45). Make a mental note for each:

  • For Q, the key thought is: "Narrow Q for surgery (like cutting feedback), Wide Q for shaping (like warming up a guitar)."

  • For Room Acoustics, think: "The room itself is part of my sound system and changes the sound."

  • For Signal Chain, think: "The sound follows a specific path; I can trace it step-by-step to find problems."

• Why: This vocabulary helps you think more precisely about your mix. It separates the idea of fixing one specific problem frequency from shaping the overall tone, and forces you to consider the room itself as a major factor in what you're hearing.

2. The "Precision & Perception" Listening Exercise.

• Action: You can do these two simple things at your next practice.

  • A. The 'Q' Control Mission: The next time you EQ, be intentional with the Q (Width) knob (#42). If you're cutting a feedback frequency, make the Q as narrow as possible. Notice how you remove the squeal without hurting the overall tone. If you're boosting a frequency to add warmth, use a wide Q and listen to how it sounds more gentle and musical. Feel the difference.

  • B. The Room Walk: While the band is practicing a song, leave the booth and walk the room. Listen to the Room Acoustics (#43). Do you hear those boomy low notes (Room Modes #44) in the back corners? Is it much clearer in the middle seats? This is Psychoacoustics (#41) in action—the sound is perceived differently everywhere. This will prove why a mix that sounds perfect at the board might not sound perfect for the congregation.

• Why: This exercise trains you in the proper, professional use of your EQ, and it gets you out of the booth to hear what your congregation actually hears. This is a massive leap in skill and awareness.

3. Unlock the #1 Secret to Fast & Calm Troubleshooting.

• Action: This week, take five quiet minutes at your soundboard to understand your Signal Chain (#45). Pick one channel, like the pastor's mic. Physically point to the signal path: Start at the top with the Gain knob, follow it down through the EQ section, past the mute button and the fader, and out to the Main Mix light. You are building a mental map of the audio's journey.

• Why: When sound suddenly stops, beginners panic. Pros calmly trace the Signal Chain. By knowing the exact path the audio takes, you can quickly check it step-by-step ("Do I have signal on the meter? Yes. Is the channel muted? No. Is the fader up? Yes."). This turns stressful guesswork into a calm, logical process for finding and fixing any problem in seconds.

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Until next time,

Church sound that slaps. Built for the volunteers in the booth, not the guys in suits.