Advance CMP Study Guide

What is a high-pass filter, and what are some benefits of using it?

known as a low-cut filter, is a key mixing tool that minimizes unwanted low-end frequencies like rumble, hum, and vocal plosives. Using it on multiple tracks can reduce accumulated muddiness and improve clarity in a mix

When panning, which tracks typically go to the center?

lead vocals, bass, kick drum, and snare are typically placed in the center. This ensures these key tracks are consistently audible on all playback systems, regardless of whether they are mono or stereo

What is the difference between SPL (Sound Pressure Level) and

dBFS (Decibels Full Scale)?

SPL (Sound Pressure Level) measures the physical loudness of sound in the real world, like what you hear with your ears. dBFS (Decibels Full Scale), on the other hand, measures the level of a digital audio signal, indicating how close it is to the maximum possible level in a digital system.

Sound exists in three domains

acoustic/analog/digital

Sound

typically starts (unless it’s electronically created) and ends with the acoustic domain

G A I N S T A G I N G

SETTING  AN  APPROPRIATE  LEVEL  THROUGHOUT  THE  RECORDING AND MIXING PROCESS

What are some consequences of poor gain staging?

Distortion or high noise floor

Reduced headroom for mixing

Why people fail at gain staging

Following old advice to "record as loud as possible" can lead to clipping. Additionally, a mix can become distorted if software instruments, loops, and beats have high default volumes, and if the overall loudness on the mix bus is not properly monitored.

MANAGING GAIN AT VARIOUS STAGES

1. Mic placement and pad switch/source output adjustment

2. Adjusting input gain on your preamp or console channel

3. Clip gain adjustment in the DAW

4. Trim/gain tool (preplugin) in the DAW if available

Why not pull the fader up or down to adjust the level?

It is not ideal to use faders for major level adjustments because they are at the end of the signal chain. This means issues like distortion or noise floor cannot be fixed by simply pulling the fader down. 

Signal flow:

Source gain → Input gain (mic pre) → Clip gain (DAW)→  Trim/gain plugins → Fader

Microphones are a type of?

transducer they convert acoustical energy (sound waves) into electrical energy (the audio signal)

ALL MICROPHONES SHARE ONE THING IN COMMON

Diaphragm: a thin piece of material that vibrates when it is struck by sound waves

3 MAIN TYPES OF MICROPHONES

DYNAMIC, RIBBON, AND CONDENSER

DYNAMIC

Ribbon

Condenser

E Q ( E Q U A L I Z A T I O N )

The process of adjusting the balance of frequencies in an audio signal— boosting, cutting, or shaping lows, mids, and highs to achieve clarity, balance, and character

Graphic Equalizer

 Fixed frequency & Q (width). It has just one control: the amount of boost or cut. Less flexible than parametric EQ

Parametric Equalizer

3 flexible controls: Frequency, Q (width), Gain.

EQ FILTERS

1. Low -Pass (high-cut) & High - Pass (low-cut) Filters

2. Bandpass Filter

3. High & Low Shelving Filters

4. Peaking (Bell) Filter

5. Notch Filter

The Frequency Bands

• High(Presence): 4kHz to 6kHz

• High-Mids: 2kHz to 4kHz

• Mid range: 500Hz to 2kHz

• Low-Mids: 250Hz to 500Hz

• Bass: 60Hz to 250Hz

• Sub-Bass: 20Hz to 60Hz

EQ GOALS

• Make an instrument sound clearer and more defined.

• Reduce the effect of masking

• Make all the elements of a mix fit together better.

• Give the mix an element of height.

EQ Rules

Cut if you’re trying to make things sound better. EQ filters are a great tool for achieving this

EQ Rules

Boost if you’re trying to make things sound different or add character

EQ Rules

take advantage of a high-pass filter. Removing below 100- 200Hz from instruments and vocals helps make room for low-end instruments such as bass, kick drum, and some low synth sounds

EQ Rules

Use a narrow Q (bandwidth) when cutting and a wide Q when boosting for natural results

EQ Rules

EQ when it’s needed and where it’s needed. Unnecessary EQ can ruin a mix.

EQ Rules

Certain EQ may sound good when soloed, but it may not work well in the context of the song. Always check your EQ with other tracks playing

Why would need to do Eq before Compression

EQ first if the track has a lot of problematic frequencies you need to cut.

Why would you do compression before EQ

Compress first if the track doesn’t have a lot of EQ problems, but is very dynamic

C O M P R E S S O R

An automated dynamics processor that reduces the dynamic range and  evens out the sound by turning down the louder signal and boost the softer signal with make-up gain

Threshold

Activates the compressor. Compression begins once the signal crosses the threshold level

Ratio

determines how aggresive the signal gets compressed

Knee

refers to how the compressor transitions between the non-non-compressed and compressed states

Attack

controls how fast the compressor reacts to the beginning of the signal once it has crossed the threshold. The attack time is the amount of time the compressor will go from zero compression to full compression

Release

controls how fast the compressor reacts to the end of the signal once it falls below the threshold. The release time determines how long it takes to go from full compression to zero compression.

Make-Up Gain or Output

allows the signal to be boosted back to its original level and beyond. Some compressors offer automatic makeup gain.

Compression: More Than Just Leveling

• It makes a track more consistent by reducing its dynamic range.

• It can add energy, excitement, sustain, and fullness.

• It can help to reveal details in a recording.

• Analog compressors can impart character and tone

Clip Gain

an excellent tool for ensuring consistent gain throughout a song, helping to eliminate unnatural fluctuations. By using this method to control the level of smaller sections like a phrase or even a single word, you can give your compressor a more consistent dynamic range to work with.

Multing

involves creating separate tracks for different sections of the song, which allows you to apply unique compression settings to each part

COMMON COMPRESSION MISTAKES

Over-compressing – This will suck the life out of your mix, especially with a fast attack time.Use compression with clear purpose and intention

COMMON COMPRESSION MISTAKES

Compressing EVERYTHING – Certain instruments such as distorted guitar and virtual drums/synth samples don’t need much compression if at all.

COMMON COMPRESSION MISTAKES

Relying solely on compression to control dynamics–Balancing/clip gain (pre-compression) and volume automation (post-compression) alongside compression will help you achieve the control you want

COMMON COMPRESSION MISTAKES

Not level-matching – Not only will you assume the compression is making it sound better (because it’s louder), but it will also disrupt the gain staging you’ve established

COMMON COMPRESSION MISTAKES

Using just one compressor to do the job -Serial compression can give you more natural and musical results. Also, it allows you to use different types of compressors in the chain, which gives you certain character and color you may look for

LUFS

(Loudness Units Full Scale) is a standardized way to measure perceived loudness, not just peak or RMS

Integrated LUFS

The overall loudness across the entire track (most important for streaming/mastering).

Short-term LUFS

Loudness measured over a 3-second window (shows dynamics oversections)

Momentary LUFS

–Loudness in very short windows (about 400ms), showing instant loudness changes.

Serial compression

Instead of tasking a single compressor to do heavy compression, use two in succession to lessen the load, which will yield more natural results

Parallel compression

Preserve the dynamic range of the dry signal while adding energy and excitement by mixing in a heavily compressed signal

Sidechain compression

Sending a track (via sends) to duck another sound. Can be used to create a rhythmic pattern also.

Mix bus compression

Used to “glue” the whole mix.