10.3 Percussion instruments and membranes
3 min read•july 24, 2024
Percussion instruments rely on vibrating membranes to create sound. These membranes generate complex wave patterns, producing unique tones and . The , size, and material of the membrane all play crucial roles in shaping the instrument's pitch and timbre.
The and air cavity of percussion instruments also significantly impact their sound. The shell's material and construction affect and tone color, while the cavity's size influences low-frequency response and sustain. Together, these elements create the rich, diverse sounds of drums and other percussion instruments.
Membrane Vibration and Percussion Instrument Acoustics
Membrane vibration principles
Top images from around the web for Membrane vibration principles
Sound Interference and Resonance: Standing Waves in Air Columns – Fundamentals of Heat, Light ... View original
Is this image relevant?
Sources of Musical Sound – University Physics Volume 1 View original
Is this image relevant?
Superposition and Interference – Fundamentals of Heat, Light & Sound View original
Is this image relevant?
Sound Interference and Resonance: Standing Waves in Air Columns – Fundamentals of Heat, Light ... View original
Is this image relevant?
Sources of Musical Sound – University Physics Volume 1 View original
Is this image relevant?
1 of 3
Top images from around the web for Membrane vibration principles
Sound Interference and Resonance: Standing Waves in Air Columns – Fundamentals of Heat, Light ... View original
Is this image relevant?
Sources of Musical Sound – University Physics Volume 1 View original
Is this image relevant?
Superposition and Interference – Fundamentals of Heat, Light & Sound View original
Is this image relevant?
Sound Interference and Resonance: Standing Waves in Air Columns – Fundamentals of Heat, Light ... View original
Is this image relevant?
Sources of Musical Sound – University Physics Volume 1 View original
Is this image relevant?
1 of 3
- Membrane fundamentals generate transverse waves in stretched circular membranes creating modes of vibration encompassing fundamental tones and overtones
- Factors affecting membrane vibration include tension influencing pitch, material properties determining timbre (density, elasticity), and size and shape of the membrane impacting resonance
- Vibrational patterns form nodal lines where membrane remains stationary and antinodes of maximum displacement, producing circular and radial modes (concentric circles, diametric lines)
- Frequency relationships in ideal membranes described by Bessel functions for mode shapes result in non-harmonic overtone ratios (unlike strings) (1 : 1.59 : 2.14 : 2.30 : 2.65)
Shell and cavity influence
- Shell functions provide structural support for the membrane, reflect and diffract sound waves, and contribute to overall timbre through resonance (wood shells add warmth, metal shells add brightness)
- Air cavity effects create Helmholtz resonance boosting certain frequencies, couple membrane and air modes enhancing sustain, and influence low-frequency response (larger cavities emphasize lower frequencies)
- Shell material and construction impact sound:
- Wood types offer varied acoustic properties ( for brightness, for warmth)
- Metal shells produce brighter, more projecting tones (, )
- Synthetic materials in modern drum design provide consistency and durability (, )
- Cavity size and shape relate to with larger cavities lowering pitch and impact sustain and decay characteristics (deeper shells generally have longer sustain)
Factors affecting percussion sound
- Pitch influencing factors include membrane tension and size with higher tension raising pitch, shell depth and diameter affecting resonance, and material density and stiffness impacting vibrational characteristics
- Timbre determining elements comprise overtone structure shaped by membrane and shell properties, shell resonances adding complexity to sound, and damping mechanisms altering decay (muffling rings, dampening gels)
- Volume control aspects involve playing technique varying stroke type and force, membrane and material affecting sensitivity and projection, and instrument size and construction determining overall loudness potential
Acoustic properties of percussion
- Membranophone categories include:
- Single-headed drums with open-ended shells (, )
- Double-headed drums with two tunable membranes (, )
- Frame drums with shallow shells (, )
- Tuning systems vary between fixed-pitch instruments like tuned to specific notes and variable-pitch instruments allowing continuous pitch changes (tabla, )
- Resonance characteristics range from short sustain in wood blocks and claves producing staccato sounds to long sustain in cymbals and gongs creating rich, complex tones
- Frequency ranges span from low-frequency instruments producing deep tones (bass drum, timpani) to high-frequency instruments generating bright, cutting sounds (cymbals, tambourine)
- Cultural and musical contexts shape instrument design and playing techniques:
- Western orchestral percussion emphasizes standardized instruments and precise tuning
- World music percussion traditions feature diverse materials and playing styles ( from West Africa, gamelan instruments from Indonesia)
Key Terms to Review (30)
Acrylic: Acrylic is a synthetic polymer that is often used in the construction of percussion instruments, particularly for drum shells and resonant membranes. Its unique properties, such as clarity, durability, and lightweight nature, make it an excellent choice for enhancing sound quality and resonance in musical applications.
Animal skin: Animal skin refers to the hide or leather obtained from animals, which is used as a material for various applications, including the construction of percussion instruments. In the context of sound production, animal skins are often stretched over a frame or body to create membranes that vibrate and produce sound when struck.
Bass Drum: The bass drum is a large percussion instrument that produces low-frequency sounds, typically struck with a mallet or beater. It plays a crucial role in both orchestral and popular music by providing the foundational rhythm and depth, making it essential for maintaining the beat and enhancing musical texture. The bass drum is characterized by its significant size and the use of a membrane, which vibrates to produce sound.
Bodhrán: The bodhrán is a traditional Irish frame drum, typically played with a wooden stick known as a tipper. This percussion instrument features a circular wooden frame with a drumhead made from animal skin, which gives it a distinctive deep sound. The bodhrán is commonly used in Irish music, providing rhythm and enhancing the overall acoustic texture of performances.
Bongos: Bongos are a pair of small, hand-played drums that are typically made from wood and have a hollow body. These percussion instruments are known for their distinctive sound, which is produced by striking the drumheads with the fingers. Bongos are often used in various music styles, especially in Latin music, and play a crucial role in creating rhythm and texture in musical compositions.
Brass: Brass is a metal alloy primarily made of copper and zinc, known for its bright gold-like appearance and excellent acoustic properties. In the context of percussion instruments, brass is commonly used to create various components, such as valves and bells, which enhance sound production and timbre. Its unique characteristics allow for a wide range of musical expression in both orchestral and solo performances.
Carbon fiber: Carbon fiber is a lightweight, high-strength material made from thin strands of carbon atoms bonded together in a crystalline structure. This material is renowned for its excellent strength-to-weight ratio and rigidity, making it a popular choice in various applications including the construction of percussion instruments where reduced mass and increased durability are critical.
Congas: Congas are tall, narrow, single-headed drums that originate from Afro-Cuban music and are commonly used in various genres, including salsa and jazz. These instruments are typically played in pairs or groups and produce a wide range of tones based on how the player strikes the drumhead, making them essential for rhythmic patterns in percussion ensembles.
Djembe: The djembe is a West African hand drum that is known for its wide range of tones and powerful sound. It is typically carved from a single piece of wood and features a drumhead made from animal skin, which is tightly secured to create different pitches and rhythms. The djembe is often played in various musical contexts, providing both rhythmic support and engaging solos.
Flam: A flam is a rudimentary drum stroke that consists of two hits played in quick succession, creating a thick, fuller sound. It typically involves a primary note played with one hand followed closely by a softer grace note played with the other hand. This technique is commonly used in various percussion instruments, especially those featuring membranes like drums, to add depth and texture to rhythm patterns.
Fundamental Frequency: Fundamental frequency refers to the lowest frequency of a periodic waveform and is often perceived as the main pitch of a sound. This frequency plays a crucial role in defining the harmonic content and timbre of sound, influencing how different instruments and voices are perceived. The fundamental frequency is essential in understanding how standing waves form, how instruments produce sound, and how we perceive pitch in our auditory environment.
Harmonics: Harmonics are specific frequencies that occur at integer multiples of a fundamental frequency, creating a rich and complex sound spectrum. The presence and relative intensity of these harmonics significantly contribute to the timbre of an instrument or voice, allowing us to distinguish between different sounds even when they play the same note. Understanding harmonics is essential for analyzing sound quality, wave interactions, and the behavior of musical instruments.
Head: In the context of percussion instruments, the 'head' refers to the membrane or surface that is struck to produce sound. This component is crucial because it directly influences the tone, pitch, and timbre of the instrument. Different materials and tension levels used for the head can create a wide variety of sounds, making it a key element in the design and performance of percussion instruments.
Mahogany: Mahogany is a type of hardwood known for its rich color, durability, and workability, often used in making various musical instruments, especially in percussion. Its density and tonal properties make it ideal for crafting drum shells and resonating bodies, enhancing sound quality and projection. Mahogany's fine grain and natural luster also add aesthetic appeal to instruments.
Maple: Maple is a type of hardwood known for its density, strength, and exceptional tonal qualities, making it a popular choice in the construction of percussion instruments and drum shells. Its fine grain and ability to produce warm, resonant sounds contribute to the quality of musical performance. This wood is often sought after for its aesthetic appeal as well as its acoustical properties.
Mylar: Mylar is a brand name for a type of polyester film made from polyethylene terephthalate (PET). Known for its durability and resistance to moisture, Mylar is commonly used in various applications, including the construction of drum heads and other percussion instruments. Its unique properties allow it to maintain tension, produce a clear sound, and withstand the rigors of performance and environmental conditions.
Overtones: Overtones are the higher frequency sound waves that occur above the fundamental frequency of a vibrating system, contributing to the overall sound quality and character. They play a significant role in shaping timbre, as different instruments produce varying overtone patterns, which help listeners distinguish between them even when they play the same note. Understanding overtones is crucial for analyzing harmonic content and the unique sonic signatures of percussion instruments and membranes.
Resonance: Resonance is the phenomenon that occurs when a system is driven by an external force at its natural frequency, resulting in an increase in amplitude and energy transfer. This effect is crucial for understanding how sound waves interact with various mediums, leading to amplified vibrations and sound intensity in musical instruments, structures, and acoustical spaces.
Roll: In the context of percussion instruments and membranes, roll refers to a rapid succession of strokes played on a drum or similar instrument, creating a continuous sound effect. This technique involves alternating between different sticks or mallets to produce a smooth, sustained tone that enhances the musical texture. It is a fundamental skill for drummers and is commonly used in various musical genres to maintain rhythm and create dynamic intensity.
Shell: In the context of percussion instruments and membranes, a shell refers to the outer structural casing that forms the body of instruments like drums. This component is crucial as it influences the tonal quality, projection, and resonance of the sound produced by the instrument. The materials, thickness, and shape of the shell all play significant roles in determining how the drum or percussion instrument sounds when played.
Snare drum: A snare drum is a cylindrical percussion instrument that consists of a shell, drumhead, and a set of snares, which are metal wires or strands stretched across the bottom head. This unique construction allows the snare drum to produce a sharp, crisp sound, making it a fundamental component in various musical genres, especially in marching bands and orchestras. Its ability to create distinctive rhythms and accents contributes significantly to both ensemble playing and solo performances.
Steel: Steel is an alloy primarily made of iron and carbon, known for its high tensile strength and durability. This material plays a crucial role in the construction and crafting of various musical instruments, particularly in strings and percussion, where its properties significantly influence sound production and quality.
Taiko: Taiko is a traditional Japanese drumming art form that emphasizes the rhythm and power of drum beats, often performed in ensembles. The word 'taiko' refers to various types of Japanese drums, as well as the performance style associated with them, showcasing not only musicality but also intricate choreography and physical expression.
Talking drum: The talking drum is a type of hourglass-shaped drum from West Africa that can mimic human speech by varying its pitch and tone. It is traditionally used for communication over long distances, often signaling important events or conveying messages between communities. The ability to reproduce the nuances of speech makes it a unique instrument in both musical and cultural contexts.
Tambourine: A tambourine is a percussion instrument consisting of a circular frame, usually made of wood or plastic, with pairs of small metal jingles called zils attached around its circumference. This instrument is classified as a membranophone due to its common inclusion of a drumhead that can be struck, producing rhythm and sound. The tambourine's distinctive sound is created when it is shaken or hit, making it popular in various music genres, including folk, rock, and classical.
Tension: Tension is the force that is transmitted through a medium, such as a string or membrane, when it is pulled tight. This force plays a crucial role in how vibrations are produced and maintained in various systems, affecting how waves propagate and create sound. Tension affects the frequency of the waves generated, influencing the pitch and tonal quality of the sounds produced by different instruments and materials.
Thickness: Thickness refers to the dimension of an object measured between its two opposite surfaces, which plays a crucial role in defining the sound characteristics of percussion instruments and membranes. It influences how vibrations travel through the material, affecting both the pitch and tone quality of the sound produced. The variation in thickness can lead to differences in resonance and damping, impacting the overall performance and acoustic properties of the instrument.
Timpani: Timpani, also known as kettledrums, are a type of tuned percussion instrument characterized by their large, bowl-shaped shells and calfskin or synthetic drumheads. They are played with mallets and are known for their distinctive pitch and resonant sound, making them a staple in orchestras and concert bands. The tension of the drumhead can be adjusted to change the pitch, allowing for melodic playing alongside rhythmic support.
Tuning system: A tuning system refers to the method or framework used to establish the pitch relationships among musical notes, which is essential for the performance and construction of instruments, particularly in percussion instruments that utilize membranes. These systems define how the frequencies of different pitches are organized and can affect the sound quality, resonance, and overall musicality of the instruments. Understanding tuning systems is crucial in creating harmonious sounds and is particularly significant for instruments that rely on tensioned membranes.
Vibration: Vibration is the mechanical oscillation of an object about an equilibrium position, characterized by repetitive motions that can produce sound waves when coupled with a medium. This phenomenon is crucial in understanding how sound is generated, transmitted, and perceived, particularly in the context of various instruments and materials that utilize membranes or surfaces to create sound.