Resource
Sounds
This is a perspective, not a rule. Below are types of sounds, classified by frequency and initial transient.
Fundamental Frequency and Transient Graph
This graph can help illustrate common functions.
Tonal
Atonal
High
Freq
Low
Keys
Pad
Pluck
Lead
Vocal
Bass
Fast
Transient
Slow
High
Freq
Low
Perc
FX
Atmos
Fast
Transient
Slow
Frequency (Freq) is the fundamental pitch of the sounds. You can imagine a dubstep bass having high frequencies, but the fundamental pitch of the bass would be low.
Transient refers to how long the note is played for. A pluck is short and quick. A pad would be a long drawn out note.
These graphs help illustate rough areas the sounds tend to occupy. They are not rules, but just an interpretation. One way to use these graphs is to interpret what a section might need. For example, you might have sounds with fast transients, and low and high frequencies. Using the graph, you could see the gaps in the graph and add a lead instrument, a pad instrument or some atmospheric elements to fill the gaps.
Tonal
Tonal sounds are sounds that have a pitch, and can be played melodically.

Keys

Keys function as harmonic instruments with articulated attacks and sustained releases. While versatile across frequency ranges, they typically occupy middle to high frequencies and provide both melodic content and harmonic structure. Their distinct timbre comes from their attack-decay-sustain-release envelope, making them essential for establishing the harmonic foundation of a track.

Frequency
Middle to High (120Hz-4kHz)
Transient
Fast (5-50ms)
Harmonic Density
Medium to High

Examples

Piano
Electric Piano
Rhodes
FM Synth
Wurlitzer

Bass

Bass instruments anchor a track through powerful low-frequency content. While the fundamental frequency must reside in the sub and low range (20-250Hz), upper harmonics can extend much higher, adding presence and character. Bass elements define the harmonic foundation and provide rhythmic momentum. Certain sounds like an 808 kick serve dual functions as both percussive and bass elements.

Frequency
Sub to Low (20-250Hz)
Transient
Variable (10-100ms)
Harmonic Density
Range from Pure to Complex

Examples

Bass Guitar
Double Bass
Synthesized Sub-bass
808 Kick
Reese Bass

Pad

Pads create texture and atmosphere through gradual attacks and sustained releases. They fill the frequency spectrum with harmonic content, providing tonal continuity and emotional context. Often used to create a sense of space and depth, pads serve as the sonic backdrop against which other elements can stand out. Their slow evolution creates a sense of movement without demanding attention.

Frequency
Wide Range (80Hz-8kHz)
Transient
Slow (100-500ms)
Harmonic Density
Variable (Simple to Rich)

Examples

String Ensemble
Choir
Ambient Synth
Mellotron
Organ

Pluck

Pluck sounds feature a distinct fast attack followed by a quick decay, creating rhythmic articulation and movement. They add energy and motion through their crisp transients while occupying the middle to high frequency range. Often used for arpeggiated patterns or rhythmic countermelodies, plucks help maintain energy and provide textural interest between other elements of the arrangement.

Frequency
Mid to High (250Hz-8kHz)
Transient
Very Fast (1-10ms)
Harmonic Density
Simple to Moderate

Examples

Harp
Pizzicato Strings
Kalimba
Arpeggiated Synth
Plucked Guitar

Lead

Lead instruments carry the primary melodic content of a track, designed to cut through the mix and capture attention. With their prominent mid to high frequencies and controlled transients, leads express the main musical ideas and emotional character. Their articulation allows for expressive performance while their timbral qualities make them instantly recognizable against the backdrop of other elements.

Frequency
Mid to High (300Hz-10kHz)
Transient
Medium-Fast (10-50ms)
Harmonic Density
Rich and Complex

Examples

Solo Violin
Lead Guitar
Supersaw Synth
Flute
Vocal Lead

Vocals

Vocals represent the most direct human element in music, combining linguistic meaning with melodic expression. Their unique timbral quality spans the full frequency range while maintaining a focused presence in the mid-range where human hearing is most sensitive. Beyond functioning as a lead element, vocals provide an immediate emotional connection through both linguistic content and paralinguistic features like tone, inflection, and breathing.

Frequency
Full Range (80Hz-12kHz)
Transient
Variable (20-80ms)
Harmonic Density
Complex and Dynamic

Examples

Lead Vocals
Backing Harmonies
Choir
Vocal Chops
Vocoder Effects
Atonal
Atonal sounds tend to not have a consistent fundamental frequency. They may have one, but normally it is other characteristics that define them, such as their timbral qualities.

Percussion

Percussion elements provide rhythmic structure and energy through their sharp transients and variable frequency content. From low-end impact to high-frequency articulation, percussion defines the temporal grid of a composition. The distinctive attack characteristics of different percussion sounds create rhythmic diversity while their spectral content adds timbral variety throughout the frequency spectrum.

Frequency
Full Range (30Hz-20kHz)
Transient
Extremely Fast (0.1-10ms)
Harmonic Density
Noise-like to Pitched

Examples

Kick Drum
Snare
Hi-Hats
Cymbals
Toms
Shakers

FX

FX elements serve transitional, ornamental, or emotional purposes in a composition. These attention-grabbing sounds create dramatic moments, signal section changes, or add sonic interest. Unlike atmospheric elements, FX are typically more discrete and event-based, drawing attention to specific moments in the timeline rather than creating continuous texture.

Frequency
Variable (20Hz-20kHz)
Transient
Context-dependent (5-200ms)
Harmonic Density
Highly Variable

Examples

Risers
Impacts
Transitions
Glitches
Sweeps

Atmosphere

Atmospheric elements create environmental context and emotional tone through sustained, evolving textures. With slow transients and complex spectral content, these sounds establish the spatial and emotional setting of a track. Unlike discrete musical elements, atmospheric sounds blend into the background, creating a sense of immersion and continuity across the composition.

Frequency
Broad Spectrum (40Hz-18kHz)
Transient
Very Slow (200ms-2s)
Harmonic Density
Complex and Evolving

Examples

Ambient Noise
Field Recordings
Wind
Rain
Natural Soundscapes

Foley

Foley sounds incorporate real-world objects and actions into the sonic palette, adding organic texture and rhythmic elements. Distinguished by their recognizable source material and naturalistic quality, foley creates a sense of physical presence and tangibility. These sounds bridge the gap between musical and environmental elements, often used for rhythmic articulation or to enhance storytelling.

Frequency
Full Range (20Hz-20kHz)
Transient
Fast to Medium (5-100ms)
Harmonic Density
Naturally Complex

Examples

Footsteps
Paper Crumpling
Door Slams
Glass Breaking
Fabric Movement
Why seperate atmosphere, FX and foley?
These types of sounds are similar, and the names used to represent them are used interchangably sometimes. Foley in a song, adds atmosphere. Some FX, like lightning could be included in a rainstorm sample. It can get confusing. They tend to not carry a tone, and they are normally added to spice up a song. By seperating these types, we can be more specific, because there does seem to be utility in having three seperate categories.

Foley tends to be more percussive because of it's fast transient. FX tends to be longer sounds, not used in distinct rhythms, but to add more texture. Atmospheres tend to be used to add a mood to a track, adding a distinct layer of sound.