ARTICLES
Below, starting with the most recently posted, are writings on musical instruments, acoustics, and related topics by Bart Hopkin. You can scroll through to find subjects that interest you, or use the search function in the menu bar above (magnifying glass icon) to search on key words of your choice.
************************************
SCALE-LOGICS
This article is about the different ways one can think about musical scales and the logic that underlies them. For any given scale you could ask, how were the particular pitches of this scale selected from the continuum? What sort of reasoning underlies the choices?...
SAMPLING A PREPARED PIANO
A while back I received an email with a suggestion: Why not create a commercial collection of audio samples featuring prepared piano sounds, using my old upright? The suggestion came from Mike Peaslee, the head of Soundiron, a company that produces and sells sample...
FIRST PRINCIPLES
Some time ago I gathered a set of stainless steel drinking water bottles, tuned them by adding suitable amounts of water, and hung them on a frame for playing by percussion. They were the kind of water bottle that has an inner and an outer shell for insulation. These...
CONJOINED STRING SYSTEMS
What happens when two or more musical strings are connected to one another? There are many ways that this idea can play out, and in this article we’ll look at some of the possibilities. The musical results can sometimes be quite interesting! You can see a version of...
NOTES ON A MINIMAL KEYBOARD INSTRUMENT
Pianos are complicated pieces of machinery. Contemporary pianos have literally thousands of moving parts; it’s mind-blowing when you think about it. And it’s amazing how well the design works: the resulting instrument is fluid, expressive, dependable, extraordinarily...
WHICH MODE DOMINATES?
If you have fooled around with the making of pitched percussion instruments from available materials, perhaps you’ve encountered this situation. You find something that produces a nice tone when you strike it – let’s say, a length of steel conduit which you’ve...
THE WINDOW GALLERY AT SAN FRANCISCO’S CENTER FOR NEW MUSIC
For the last decade I’ve been serving as one of the curators at a the Window Gallery, an exhibit space for new instruments and sound art. It’s a project of the Center for New Music in San Francisco, housed in the Center’s location in San Francisco’s Tenderloin...
SHARED RESONANCES
Most musical instruments have a primary vibrating body that serves as the main determinant of the frequencies we hear – think of the string itself in a string instrument, or the bar in a marimba. And then, most of those instruments have additional components which...
MORE ON MEMBRANE REEDS
This essay is designed to accompany a video called Membrane Reeds which can be viewed here on Youtube. In it you can see and hear a variety of membrane reed instruments, but the video doesn’t go into much detail on how to build the instruments, nor does it address the...
NORTH-SOUTH/EAST-WEST CHIMES (a Description)
Some time ago I posted on this site an essay under the title “Orientation of the Oscillation.” In it I talked about the importance of the direction of the oscillation in an instrument’s main vibrating bodies (strings, bars, tines or whatever): how the orientation of...
WHAT-A-SHAME: Design and Construction
What-a-Shame is the name of a musical instrument I designed long ago, and this article tells you what you need to know to build it. The article is not a step-by-step how-to; rather it outlines the underlying ideas and provides the necessary information while leaving...
WOOD AND BUTTER
Around the same time this article was posted, I uploaded this Youtube video showing in action the sound instrument called Wood & Butter. The video doesn’t include descriptions of or additional information about the instrument. That’s the purpose of this article:...
HOCKETING
I recently uploaded YouTube a video showing some hocketing instruments. This post provides a bit more detail on the instruments used in that video for anyone who may be interested. The term "hocketing" refers to music making with rapid alternation between members of...
TUBULAR CHIMES, ALTERED
This article is written to accompany the video called "Tubular Chimes, Altered", which you can find posted online here. The video shows several modifications you can make to simple tubular chimes to create more varied and interesting chime sounds. The descriptions in...
POTWOT: A Torsional Musical Instrument
Most musical instruments are designed to work with one or the other of two types of vibratory movement: transverse or longitudinal. Very Loosely speaking, transverse vibration typically involves cross-wise movements in the vibratory medium; it is what we normally see...
COIL SPRINGS AS SOUND SOURCES
Coil springs can make very interesting sounds, and a lot of experimental instrument makers and sound seekers have worked with them. This article looks at some of the sound possibilities that coil springs present.
ROTARY MUSIC MACHINES
Simple home-buildable music machines.
SCRAPING
An exploration of the sonic world of scrape, and description of a battery of scraped instruments analogous to drum set.
SOUND INVENTIONS: Selected Articles from Experimental Musical Instruments
From Routledge Press, a newly released collection of articles from the late great Experimental Musical Instruments journal.
THE SPEAKER DRIVER INSTRUMENT
The components in the photo on this page make up a musical instrument called the Speaker Driver Instrument. The elements of it, you can see, are an inexpensive little electronic keyboard, a stereo amplifier, a speaker driver minus its speaker cone, and a scrap of...
GUITAR-LIKE-THINGS
Hooray for through-and-through originality: It’s wonderful when a newly conceived musical instrument presents a whole new musical landscape to explore. On the other hand, there’s also value in presenting a new instrument idea with at least some familiar elements –...
STRING LATTICE GUITAR
In this post you’ll find a description of a potentially very interesting idea in string instrument design. But as you’ll see as you near the end of the post, my attempt to exploit the idea wasn’t terribly successful. Still, it’s an interesting enough concept to...
SPOOLS & WHEELS
A melodic friction drum set
THREE PASSAGES FROM *INNER CHAPTERS*
A video featuring an ostinato machine and lots of animation.
SOLOWAY SIREN AND SAXTON SAVART
Two events-per-second instruments: Savart’s Wheel and Musical Siren, with a focus on how to tune for just and equal-tempered scales on instruments of this sort.
FLOPPING OVER
Floppy bands of spring steel can be the produce wonderful sounds. This post describes several musical instruments by Bart Hopkin which use such bands.
MORE SAMPLE LIBRARIES
Sample Libraries from SoundIron featuring instruments made by Bart Hopkin
ICICLES AND MORE
Four musical instruments using freely suspended stainless steel resonators.
SCHMEARY GLISSARY
Schmeary Glissary is an 84-tone Equal-Temperament Tubulon
SLOPPINESS
Perfectionism in music-making brings exquisite music into the world. But un-perfectionism brings another sort of richness.
ANIMATIONS
I have been exploring the idea of creating animated videos to accompany music made on my instruments …
ADDITIONAL NOTES PERTAINING TO HOMEMADE WOODWIND MAKING
Making home-made wind instruments: creating register holes, shaping the “lay” of a single reed mouthpiece, and more.
MORE ‘MOE
‘Moes are wind instruments which have a pitch-control system involving an open slit and a magnetic strip. This article discusses recent work developments in the ‘Moe family.
FORCED VIBRATION
Most instruments produce sound by taking advantage of a natural springiness in things. Far fewer are instruments which create a forced oscillation at specific frequencies.
NAMES AND APPEARANCES
Does it matter if a new instrument sports a catchy name? Does it matter if it is attractive to the eye?
SORRY-ASS ORGAN
The making of a very crude beating reed organ.
THE WINDOW OF AUDIBILITY
Most acoustic sound sources produce many frequencies simultaneously, resulting from multiple modes of vibration present in the vibrating body. This article addresses the question of which of these are likely to be most prominent in the tone and to be recognized as the defining pitch.
IMPEDANCE
Getting the impedance relationships right: for many types of musical instruments, this is one of the less appreciated, less understood, and more important aspects of instrument making.
INSTRUMENTARIUM HOPKINIS SAMPLE LIBRARIES
Selected Instruments of the Hopkin Instrumentarium are now to be sampled and released in a series of sample libraries. This is a new filed for Bart, the instrument maker, and in this post he talks about first impressions.
PALINDROMES
(The Only Article On This Website That’s Not About Musical Instruments.)
EVERYONE WANTS BEACH-FRONT REAL ESTATE
An article about magnetic pickups and how best to utilize finite pickup footage space.
ELASTIC STRINGS
Musical strings made from elastic materials bands make an appealing sound. This article discusses the ins and outs of putting them to use, and the various types of elastic material that can serve. It then describes some elastic string instruments that the author has made.
AGITATION PIPES
Broad spectrum sounds filtered through tubular air chambers with well defined resonance frequencies: this idea can produce very interesting musical results. This article discusses several instruments that work this way.
MUSICAL INSTRUMENT CATEGORIZATION SYSTEMS
Taxonomony is typically one of the first topics addressed in Organology 101. Here’s my take on the subject.
ADVENTURES IN FRICTION
An overview of different ways of creating friction vibrations, a discussion of principles and techniques pertaining to the making of friction instruments, and short descriptions of several friction instruments I’ve made.
FUNDAMENTAL, HARMONICS, OVERTONES, PARTIALS, MODES
Thoughts about the terminology used in talking about the multiple-frequency blends that make up musical and non-musical sounds, and how that terminology relates to the underlying physical reality and the ear’s ways of perceiving such blends.
ALUMINUM DISK GONGS (Article #2)
The second of two articles on making and tuning simple disk gongs. This one describes an approach to tuning that is more sophisticated than the rudimentary approach described in the first article, and addresses the underlying acoustics more than the previous one.
ALUMINUM DISK GONGS (Article #1)
The first of two articles on making simple disk gongs. This one outlines the simpler approach; the other takes on acoustics and tuning questions in a more sophisticated way.
ALTERNATIVES FOR PITCH CONTROL IN WIND INSTRUMENTS
An overview of systems that can be used for controlling pitch in wind instruments, from familiar an conventional to unusual and far-out.
PLAY HERE
An interactive public sound installation.
SOUNDS AND SILENCE
Thoughts on the search for quiet in a noisy world.
ENGRAVINGS OF EARLY ACOUSTICAL APPARATUS
Depictions of apparatus created in the late 19th century for experimentation and demonstrations in musical acoustics.
MASTERY VS. GO-FOR-A-RIDE
With many new instruments it’s both more fun and more musically fruitful not to try to become a virtuoso, but rather to keep an exploratory attitude that lets the instrument take you where it will.
OVER-UNDER SCALES
Notes on the Over-Under scales, on a complementary pair of just scales used in a couple of recent instruments.
THERE IS NOTHING NEW UNDER THE SUN
Notes on the question of patenting for new instruments. (Is it worth it?)
OVERTONES HARMONIC AND INHARMONIC
Notes on different sorts of overtone recipes within musical tones, and the ear’s responses to them.
THE TERRITORY BETWEEN CLEAR PITCH AND PURE NOISE
What is it about some sounds that gives them clear pitch, while other sounds come across as pitchless noise?
ORIENTATION OF THE OSCILLATION
As a matter of effective design, for some types of instruments it’s worth thinking about the direction of excitation and the orientation of the resulting vibration.
MAN, WHAT A WEIRD WORLD THAT WOULD BE (Where would we be without Hooke’s Law?)
When oscillating systems go nonlinear …
SYNTHESIS vs SAMPLING
Artifice or Nature?
SCALE AND TIMBRE
Looking for meaningful harmonic and melodic relationships in the overtone relationships inherent in different sounds, both harmonic and inharmonic.