Welcome to the Audio 101 Document for the Biltmore Church audio team!

Gain Staging

What is Gain Staging?

• The various ways to attenuate gain include:
• Gain from the source itself - This includes things such as:
• A guitar player turning up their amp/modeler
• A keys player turning up the main output of their keyboard
• A bass player turning on/off the -20dB Pad on a DI box
• Analog Gain - Preamp gain. The first mode of gain at the beginning of the ("Analog" is the term Yamaha uses to refer to gain added directly at the preamp of the Rio Rack, Omni Input at back of console, etc)
• Digital Gain - Gain that is added at the beginning of the digital signal chain within the console
• DYN 1 or 2 - Compressors or expanders with output gain
• EQ - Each EQ on a Yamaha console has an "EQ Attenuation" feature. This is simply another way of adding/subtracting gain at specific frequencies.
• Inserts - These FX slots could include anything from compressors and EQs to reverbs or amp simulators. Almost all of these feature some sort of output gain adjustment.

• Why metering gain matters:
• Prevents Clipping - Proper metering keeps audio peaks out of the red zone where clipping occurs. Clipping is the distortion that happens to the waveform when an audio signal exceeds the maximum limit or capacity of the system, software or device.
• Maintains Headroom- This is additional space allowed above the audio peaks before clipping occurs.



Digital peak meter with ranges displayed.

Digital peak meter with ranges displayed.



Visual illustration of what happens to the wave form when clipping occurs.

Visual illustration of what happens to the wave form when clipping occurs.

• Types of meters:
• Peak meters (as shown above) show instantaneous signal maximums.
• RMS meters show an average of signal strength over a short window of time.
• VU Meters show an average of signal levels emulating analog needle behavior.



Peak Meter

Peak Meter



RMS Meter

RMS Meter



VU Meter

VU Meter

Dynamics Processing

Compression

• Compressors are incredible tools for managing the dynamic range, maintaining a balanced mix, and helping achieve clarity.
• The main controls on a compressor are:
• Threshold- This is level at which the compressor engages.
• Attack - How quickly the compressor fully engages once the Threshold has been surpassed.
• Release - How quickly the compressor to fully disengages once the signal has dipped below the Threshold
• Ratio - How many dB of gain is reduced. Displayed as a x:1 Ratio (eg, a 4:1 Ratio means that for every 4dB of gain that is over the Threshold, only 1dB will be it allowed to pass unaffected)
• Makeup Gain / Out Gain - Allows you to attenuate the strength of the signal after the reduction made by the compressor.
• This is illustrated below:



The first half of this audio waveform is being reduced because is above the threshold

The first half of this audio waveform is being reduced because is above the threshold

Gates

• Gates are an incredible tool to use to improve input isolation, especially on a drums, and overall volume by cutting the noise allowed into a source and thus through your PA.
• The main controls on a gate are very similar to those found on a compressor. They are:
• Threshold: The level at which the gate engages
• Attack: How quickly the gate engages once the signal passes the threshold
• Range or Depth: How much the signal is reduced when the gate closes. Instead of completely muting the audio, you can set the range to let a quiet, natural-sounding version of the background signal pass through. The larger the range the more the signal below the threshold is being "muted."
• Hold: How long the gate is open
• Decay/Release: How quickly the gate disengages after the signal drops below the threshold level



Gate on a console

Gate on a console



The red line shows your threshold. The smaller waves highlighted by the noise bracket is below the threshold thus being cut or muted by the gate.

The red line shows your threshold. The smaller waves highlighted by the noise bracket is below the threshold thus being cut or muted by the gate.

De-Essers

• De-essers are great to help tame a vocalist's harsh "S" sounds by only dipping when the sibilant frequency range reaches the de-esser's threshold
• De-essers have similar controls to other dynamics processors, such as:
• Threshold - The level at which the de-esser engages
• Frequency - The specific range of the EQ spectrum where the sibilance is happening
• Q - The width of the EQ band being dampened



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Dynamic EQ

• Dynamic EQ controls are quite literally the combination of EQ and compression controls:
• EQ controls:
• Frequency - selects the center of the range of frequencies you want to target
• Gain - sets the maximum amount of boost or cut that can happen
• Q - adjusts how wide or narrow the frequency selection is
• Compression controls:
• Threshold - the level the signal must cross before the EQ engages
• Attack - how fast the EQ reaches its full cut or boost once triggered
• Ratio - how much the specified range of frequencies are reduced
• Release - how quickly the EQ disengages



Note how each band of this Dynamic EQ has Threshold, Range, Attack, and Release controls to allow frequencies to be cut or boosted when it meets the threshold

Note how each band of this Dynamic EQ has Threshold, Range, Attack, and Release controls to allow frequencies to be cut or boosted when it meets the threshold

EQ

What is EQ?

• EQ is an essential tool in your audio engineering tool belt. It is the primary way to shape the tone of an audio source.
• EQ controls consist of:
• Gain - The amount of boosting/cutting you are doing
• Frequency - The specific range of the EQ spectrum where the boost/cut is happening
• Q - The width of the band you are boosting/cutting
• EQ is oftentimes the first thing we reach for when encountering a “bad sounding" audio source. However, there are some things that should be kept in mind while using EQ
• Take a look at these next two examples of a vocal EQ and note the contrast between them:



An example of a bad EQ. Nearly all bands are turned down, giving the illusion of “feedback prevention.” In reality, you are just turning down the volume

An example of a bad EQ. Nearly all bands are turned down, giving the illusion of “feedback prevention.” In reality, you are just turning down the volume



An example of a good EQ. The low end rumble has been removed with a High-Pass Filter, and a couple of “problem” frequencies have been slightly lowered. This will do a good job of making a source sound clear, yet full

An example of a good EQ. The low end rumble has been removed with a High-Pass Filter, and a couple of “problem” frequencies have been slightly lowered. This will do a good job of making a source sound clear, yet full

• In these examples, it is easy to see how quickly things can go wrong, especially if feedback problems arise in the middle of a song or service. The knee-jerk reaction is to pull down as many bands as quickly as possible. However, there are 2 main things you can learn to help combat these issues:
• Learn to read the RTA (realtime analysis) meters on your channel EQ and your VSC computer software. These will help you see which frequencies are the loudest, and you can adjust accordingly.



An example of an RTA meter

An example of an RTA meter

EQ Cheatsheet



What does it sound like?

What does it sound like?

Drums

• Kick
• 30 to 50 Hz - Bottom: The tone of the reverberation in the drum shell, sometimes too rumbly, can be undefined/indeterminate depending on the mic'ing/speakers
• 50 to 100 Hz - Thump: The "punch you in the chest" range of the kick
• 100 to 200 Hz - Body: This is the “tone" of the kick sound
• 200 to 2,000 Hz - Ring/Hollowness: This large band is where you can often find issues with ringing and muddy kick sounds
• 2,000 to 5,000 Hz - Attack: This is the range to look for the "click" sound of the beater
• Snare
• 200 to 400 Hz - Body/Bottom: The central fundamental of most snares tends to live somewhere in this range. Boost around 200Hz for that "worship snare" sound
• 400 to 800 Hz - Ring: This is the range that tends to give that hollow "ring" to a snare tone that's often undesirable. Careful not to crush this range too much, though, or your snare will start to lose life and sound two-dimensional in the mix
• 2,000 to 4,000 Hz - Attack: The stick on the head "crack" is often found here. Even up as high as around 8,000 Hz you’ll find the sizzle and snap. The overtone sound of the snares themselves can either be accented or dampened somewhere around this point
• Toms
• 100 to 300 Hz - Body: Depends on tuning, but a good place to look for the "boom" of a tom sound. Too much and things will sound, well, "boomy." Remove too much, and your toms will sound thin.
• 500-900 Hz - Honk/Boxiness: This is an important area to listen to in the toms, there can be a distinct buildup of un-musical tones here that can be described as sounding “boxy” or “honky”. Try boosting around 700 Hz and you’ll hear exactly what this sounds like!
• 3,000 to 4,000 Hz - Attack: Just as it sounds, this is the the attack of the drum itself from a stick hitting its head

Bass

• 40 to 80 Hz - Bottom: Especially with five-string variations, this is where the bottom resonances of most bass guitars live
• 80 to 200 Hz - Fundamentals: The primary fundamental of the bass. Right around 180 to 200 Hz is where you can try to cut on a bass that is too "boomy" to clean it up while still preserving it’s fundamentals
• 200 to 600 Hz - Overtones: These are the upper harmonics of most bass tones, depending on the sound you're interested in. If you're having trouble getting a bass to cut through in a mix, especially a low-end heavy one or one that's getting played back on smaller speakers, this can be where to look
• 800 to 1,600k Hz - Bite: The growl and attack of most basses can be either emphasized or toned down around here
• 2,000 to 5,000 Hz - String Noise: All the slide noises and slap sounds

Guitars

• Acoustic
• 120 to 200 Hz - Boom/Body: This is where you'll find most of the explosive low end on a mic'd acoustic that tends to feedback in the live world. A little bit here adds warmth and fullness on a solo performance, but in a dense band mix, it's probably best to just get it out of the way
• 200 to 400 Hz - Thickness/Wood: This is the main "body" of most acoustic tones. Too many cuts here, and you're going to somewhat lose the life of the guitar.
• 2,000 Hz - Definition/Harshness: This double-edged sword of frequency bands will give the definition to the acoustic tone to hear the intricacies in chords and picking, but too much will make it harsh and aggressive
• 7,000 Hz - Air/Sparkle: A touch, and I mean a touch, of a shelf boost here can help open up an acoustic sound
• Electric
• 80 to 90 Hz and below - Mud: Lose it, crush it with your HP filter. There's pretty much nothing useful down here, and it will almost always just equate to flabbiness and noise in your tone
• 150 to 200 Hz - Thickness: This is where the "guts" of a guitar normally come from, but again, it can quickly cloud a mix on you. Use sparingly, perhaps automate to add sweetness to a solo section or an exposed part, and then tuck it away when things thicken up again
• 300 to 1,000 Hz - Energy: The "life" of the electric. Many of the things that make an electric sound like an electric live in this range. So attenuating needs to be taken into careful consideration. Too much though, and you start fighting with your snare and things like that, so take note
• 1,000 to 2,000 Hz - Honk: This is where honky and harsh characteristics can usually be smoothed out with a wide cut centered somewhere in this range
• 3,000 to 8,000 Hz - Brilliance and Presence: This is the range that can add shimmer or allow a guitar to cut through a mix when boosted. It can also be where you make cuts to keep a guitar from conflicting with a vocal. If making boosts in this range, keep an eye (ear?) out for noise, as any noise present from distortion/effects pedals will very quickly be accentuated as well

Keys/Tracks

• Piano
• 100 to 200 Hz - Boom: This can be a great place to add a little warmth to a solo piano in a more acoustic environment, but more often than not, this will be the first place to cut some of the girth in a piano in a mix or to help reduce feedback potential in a live situation
• 3,000 Hz and Above - Presence: Adding a little "air" here can be great to brighten up a dark piano tone, depending on mic placement. Be careful not to bring out the noise of dampers on strings (particularly in the 3,000 to 5,000 Hz range), as this can quickly become distracting and quite jarring
• Synth/Tracks
• 400 to 600 Hz - Thickness: Many synth sounds can get kind of muddy in this range and mess with the clarity of the sound itself, especially when you start layering multiple synths. Searching somewhere in this range is a good place to start
• 1,000 to 2,000 Hz - Cut/Bite: This is where you can usually find the attributes of a synth patch that are going to help it poke through the mix. Or you can cut here to help tuck it back in the mix and get it out of the way of things like guitars and vocals.
• 3,000 to 4,000 Hz - Presence/Clarity: Also like voice and guitar, this range helps add excitement to a sound. And also like just about everything else mentioned here, too much of a good thing can be painful

Vocals

• 100 Hz and below - Rumble: For most vocals, all you'll find down here is mic-handling noise, stage/floor vibrations, air conditioners, etc. Get rid of it using your high pass filter.
• 160 to 250 Hz - Boom: This is the heavy muddy or "woofy" range. Some individuals have deep chest voices and this range is important. For female and other vocalists with a higher range this can be an additional range that allows noise into the mic. Roll up your high pass filter to get rid of this.



Distance from mic to experience Proximity Effect

Distance from mic to experience Proximity Effect



Proximity Effect visualized on an EQ graph

Proximity Effect visualized on an EQ graph

• 300 to 500 Hz - Nasality: This is the frequency range is usually where you'll find the "head cold" sound. The female voice may run a little higher, but this is the ballpark. Think of someone with allergies or sinus issues
• 800 to 1,000 Hz - Clarity: Not enough of this range and the intelligibility of some lyrics may struggle to be heard
• 3,000 Hz - Presence/Excitement: This is right around the point that tends to add some energy, or some "buzz" to a vocal. Not enough, and the vocal may sound deflated, flat, and dull. Too much, and your listener will feel like he or she is getting poked in the ear canal with a chopstick every time the vocalist opens his or her mouth
• 4,000 to 8,000 Hz - Sizzle/Sibilants: Typically this is the range a de-esser is handling. If your vocalist sounds like meat hitting a hot pan at the end of any word ending in "s" or a similar sound, this is where to hunt
• 10,000 Hz and up - Air: Want to "open up" your vocal a little? Apply a light shelf boost around here and that should do it. This is not always necessary, though, and simply adding "air" for the sake of it can make things harsh, brittle, and introduce unwanted noise to the sound

Mic Technique

• Proper vocal mic placement for a live performance: hold the microphone about 1 to 2 fingers (1 inch) away from your mouth, pointed straight at your lips, at a 45-degree angle. Always grip the lower handle, never cup the grille
• It is also important not to hold a wireless mic from the very bottom. This small part that extends out is the microphones antenna. In some cases, covering the antenna can cause the mic to drop out, causing signal loss



The different sections of a microphone

The different sections of a microphone

Routing

DCAs

• A DCA (Digital Control Amplifier) derives its name from the VCA (Voltage Control Amplifier) of old school analog consoles. The difference is the consoles that they live on and how that console processes audio signal. VCAs use physical electrical voltage to control the analog audio hardware, as apposed to DCAs that use digital math and software to maintain on one fader the proportional relation of all assigned channels to where their individual faders are set.

Mix Buses, Matrices, & the ST Bus

• Mix Bus vs. Matrix vs. Stereo Bus
• Input Channels (abbr. as CH1) are where your sources (drums, mics, tracks, etc.) arrive at the console.
• Mix Buses (abbr. as "MX1") are a way of sending sources to single point for grouping, processing, and routing.
• The Stereo Bus (abbr. as "ST Bus" or "ST A, ST B") is a way of sending Channels and/or Mix Buses to a single point for grouping, processing and routing.
• Matrices (abbr. as "MT1") are a point for all sources to arrive at to be combined and then fed to separate speaker arrangements.

• Your overall console should be routed as follows:



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• All instruments and vocal mics are sent to buses for processing, then sent to the ST Bus. Other sources, such as the announce mics or the GFX computers are simply sent straight to the ST Bus without the need for bus processing