The cover initially appears almost empty. Maria W Horn’s name floats faintly near the top of a white square, while the image beneath it seems to have been erased by snow, overexposure or some material pressed across the surface. Only after sustained looking does a landscape begin to emerge. A dark vertical form stands near the center, surrounded by rock, trees, ice and uneven ground, although none of those things becomes completely certain. The picture is not hidden behind a removable layer. Its concealment is built into the act of seeing.
Epistasis works the same way. Its four pieces contain strong chords, acoustic instruments, electronic synthesis and structures precise enough to be explained technically, but their emotional shape does not arrive immediately. Relationships appear gradually. A piano figure that first seems solitary acquires several shadows. Strings that sound like one enormous body reveal divisions between live players, recordings and electric-guitar feedback. Two organists appear to sustain fixed harmony until their separate breathing cycles begin moving the music through almost imperceptible changes. Nothing remains exactly what it sounded like at first.
The scientific word “epistasis” describes a condition in which the expression or effect of one gene is altered by one or more other genes. An individual component cannot be understood fully in isolation because its behavior depends upon the surrounding system. Whether or not the album title is intended as a literal biological program, the concept offers an unusually precise way of hearing the record. Piano, code, strings, breath, amplification, playback and architectural space do not merely accumulate. Each changes what the others are capable of meaning.
This is especially apparent in the two “Interlocked Cycles” pieces that open and close the album. They originated inside a larger audiovisual work for multichannel loudspeakers and synchronized lights. Maria W Horn began from a state of low sensory activity and gradually increased tempo and density until the listener approached overload. Each sound channel corresponded with an LED placed upon a speaker, so rhythm became visible throughout the room. The audience was not simply hearing a composition while watching lights illustrate it. Sound and light joined into one perceptual mechanism.
For the album, Horn translated portions of that installation into works for Disklavier, a computer-controlled acoustic piano, accompanied by electronic material generated through the SuperCollider programming environment. The instrument is immediately paradoxical. A piano is among the strongest symbols of human instrumental tradition: wooden body, metal strings, weighted keys, touch, practice and the physical intelligence accumulated through generations of performers. The Disklavier retains that recognizable body while allowing instructions to arrive without fingers.
“Interlocked Cycles I” begins with a small arpeggiated figure whose sadness and clarity make the machine sound almost defenseless. The notes do not announce technological complexity. They enter one after another with the plainness of a music box found in an unheated room. Yet the pattern is not alone for long. Additional figures begin appearing, slightly displaced and operating according to related but independent cycles. What sounded like a melody becomes one gear inside a larger device.
The word “interlocked” is more important than “repeated.” Repetition can describe one object returning unchanged. Interlocking requires several objects whose separate movements continually alter their combined form. The piano figures may each remain relatively simple, but their points of contact migrate as the cycles accelerate. A note that initially provided closure may later function as an entrance. The same figure changes meaning without changing its identity.
Horn’s electronic layers add another uncertainty. Synthetic tones hover, whine and gather beneath the piano, sometimes behaving like extensions of the instrument’s resonance and sometimes like another organism approaching from outside. The ear tries to divide acoustic sound from artificial sound, but the border becomes unreliable. The physically vibrating piano has been activated by digital instruction, while the electronic material responds with almost bodily warmth and instability.
This produces one of the album’s central questions: where does authenticity reside when a machine plays an acoustic instrument? It cannot reside simply in the source of the sound. The piano strings are physically real, but the hands are absent. The electronic frequencies are generated through code, but the code was designed, adjusted and listened to by a person. Human intention and mechanical precision do not occupy opposite sides. They repeatedly modify each other.
Horn has described composition with generative systems as a call-and-response exchange. She writes an instruction, listens to the machine’s answer and then changes the instruction according to what she hears. The machine does exactly what its framework permits, but the musical value is not contained entirely inside the initial command. It appears through the feedback relationship between system and listener. Composition becomes less like dictating a finished object and more like cultivating a behavior.
This makes the gradual acceleration of “Interlocked Cycles I” feel both controlled and alive. Every layer belongs to a planned structure, yet the resulting field seems to grow according to laws larger than any individual line. The piece becomes warmer and brighter as density increases, but brightness does not guarantee comfort. The accumulating notes begin approaching the threshold where pattern turns into weather. The listener can no longer follow every movement individually and must either resist the excess or surrender to the total field.
The original synchronization with light helps explain this sensory transformation even when the album is heard without its visual component. At a low rate of change, the mind can identify separate events. As speed and density increase, events begin merging into textures. The listener does not simply hear more notes. The mode of perception changes. A sequence becomes shimmer; rhythm becomes apparent illumination.
The title track replaces the piano’s mechanized multiplicity with strings, but the relationship between living performer and reproduced double becomes even more direct. “Epistasis” was composed as an eight-voice double string quartet. Four parts are performed by a live quartet while another four are supplied through playback. Each musician therefore exists beside a recorded counterpart that resembles the ensemble without sharing its present time.
This arrangement creates a ghost orchestra without relying upon theatrical supernatural effects. The recorded strings cannot adjust their timing, intonation or pressure in response to the room. They proceed according to an already completed performance. The live players must inhabit a structure containing their own unreachable relatives, voices produced by musicians in another moment and preserved with permanent certainty.
The distinction becomes difficult to hear once the layers thicken. Violin, viola and cello tones overlap until the ensemble behaves like one massive instrument. Amplification enhances and distorts the strings’ spectral details, while feedbacking electric guitars introduce another layer whose relationship to the bowed instruments is deliberately obscured. A guitar can disappear into the grain of a cello; a violin overtone can acquire the electrical edge of an amplifier approaching instability.
The F-minor progressions draw upon harmonic structures Horn associated with early-1990s doom and black metal. The connection is not expressed through blast beats, shrieked vocals or familiar metal production. It lies in the emotional behavior of harmony: minor movement carried with enough duration and density that the chord stops functioning as accompaniment and becomes an environment.
Metal has always understood that sustained distortion can alter physical scale. A guitar chord played cleanly remains attached to strings and fingers; heavily amplified and allowed to continue, it can resemble weather, architecture or an approaching geological event. Horn transfers that knowledge into a string composition. The quartet does not imitate a metal band. It uncovers a common material territory where bow pressure, harmonic saturation and amplifier feedback create related forms of weight.
The title piece begins quietly enough that its danger can be missed. Long tones enter with ceremonial restraint, and the harmony appears almost devotional. Yet the doubling destabilizes the apparent calm. Each sound carries another sound inside or behind it. Slight differences in attack, tuning and texture produce beating patterns, rough edges and internal motion. Stillness becomes crowded.
This is where the genetic meaning of epistasis becomes especially useful as a metaphor. No single string line contains the piece’s full emotional character. The effect of each line depends upon the others surrounding it. A consonant tone may become threatening when placed against its recorded double. A guitar overtone may expose a dissonance previously hidden inside the strings. Volume does not simply make the material more intense; it changes the relationships among its internal frequencies.
The composition eventually achieves something close to an anthem, but without a voice or collective slogan placed at its center. Its grandeur emerges from the players becoming less individually identifiable. Eight lines press forward until the distinction among performer, playback and feedback becomes secondary to the enormous shared body they have created.
There is a political possibility inside this method, even though Epistasis is less explicitly historical than Horn’s preceding album, Kontrapoetik. Collective power does not require individuals to become identical. It can arise from distinct parts altering one another while remaining separate. The danger lies in the same mechanism. A system can enlarge beauty, pressure, fear or violence depending upon the relations it permits to develop.
The title track’s quietest passages are therefore among its most unsettling. Loudness tells the body clearly that force is present. Quiet sustained tones ask the listener to search for it. Small pulsations and interference become magnified by attention. The music does not need to strike because the listener has already leaned closer.
“Konvektion” changes the atmosphere from blackened strings to organ, but the album’s interest in interacting systems becomes even more intimate. Two organists perform upon the same instrument. Their pitches are predetermined, yet the duration of each dyad is measured through the individual breath of the performer responsible for it. The music is scored, but its temporal life depends upon two respiratory systems that cannot become mechanically identical.
The title refers to convection, the circulation created when differences in temperature or density cause material to rise, fall and move through a larger body. The organ piece creates an equivalent process from sustained tones. One dyad enters, another follows, and the interaction among pitches produces slowly shifting harmonic pressure. Nothing travels melodically in a conventional way, but the sound circulates.
The two players share one instrument while remaining physically separate. Each breath determines how long a portion of the chord survives. When one person reaches the end of an exhalation, the harmonic environment changes according to a bodily limit rather than an abstract clock. The composition’s glacial pace is therefore built from small acts of respiration.
This is an extraordinary reversal of the organ’s traditional symbolic power. The pipe organ can appear superhuman, an architectural instrument capable of filling a church with sound far larger than the person at its keyboard. “Konvektion” allows two quiet human lungs to govern that enormous mechanism. The building-sized voice remains dependent upon bodies that must repeatedly inhale.
Horn drew structural inspiration from Arvo Pärt’s tintinnabuli technique, where stepwise melodic movement interacts with triadic material. Her four-note chords are divided into dyads, allowing the two performers’ breath cycles to separate and reconnect them. The result possesses some of Pärt’s tonal clarity, but it is less like a bell heard across open air than several bells suspended within a field of electrical pressure.
Electronic interference tones unfold alongside the organ, producing beating patterns at high and low frequencies. When two close frequencies sound together, the listener perceives an additional pulsation created by their difference. No performer plays this pulse directly. It appears between tones, an audible consequence of relationship.
That may be the album’s purest form of epistasis. The new event belongs to neither source alone. It exists only because the sources coexist.
The beating patterns also make the apparently static organ physically active. Sustained chords tremble from within, and the listener’s position in relation to the speakers can change the prominence of particular frequencies. The composition occurs partly in the room and partly inside the hearing system. A person turning their head may encounter another balance, as though the piece contains corridors accessible only through bodily movement.
Horn’s interest in creating perceptual rooms is crucial here. Sound is not simply transmitted toward a passive listener. It reorganizes the conditions under which listening takes place. The person becomes aware of scale, duration, bodily location and the limits of attention. “Konvektion” may feel peaceful at one moment and oppressive at another without changing its basic material. The perceptual state of the listener has become one of the interacting components.
The use of breath keeps the work from becoming purely architectural. Every long tone contains the knowledge that somebody cannot hold it forever. One performer’s capacity differs from the other’s, and the score must live through those differences. The organ may suggest eternity, but the timing continually returns to mortality.
This makes “Konvektion” spiritual without requiring it to declare a religion. It stages the encounter between a sound culturally associated with sacred architecture and the ordinary biological process that keeps two people alive. Breath gives measure to the supposedly immeasurable.
“Interlocked Cycles II” returns to the Disklavier and electronic world, but the journey through strings and organ has changed how the machine is heard. Piano attacks now seem connected to bows beginning tones and lungs determining durations. The mechanical cycle is no longer opposed to the human body. It becomes another method through which time is divided and released.
The second cycle feels darker and more dramatic than the first. Chordal motion carries greater weight beneath the accumulating piano figures, and the electronics introduce an uneasy depth. The opening piece moved from music-box isolation toward luminous saturation. Its companion sounds more aware that increasing complexity can produce pressure as easily as wonder.
The repeated structure does not make the final piece a return to the beginning. Cycles are altered by everything that happens during their apparent absence. A listener encountering the Disklavier after the title track and “Konvektion” brings those experiences back into it. The same relationship between programmed precision and acoustic vibration now contains strings, feedback, breath and organ memory.
This is how the album avoids the closed circle implied by its frame. “Interlocked Cycles II” is not simply the second half of a symmetrical design. It demonstrates that return is never neutral. A cycle may arrive at the same formal point while carrying a different history.
The final minutes gradually remove some of the harmonic weight, leaving smaller attacks and resonances exposed. Muted or rattling piano textures appear close to the physical mechanism, as though the instrument has turned its polished musical surface aside and allowed us to hear the machinery operating underneath.
The album does not end by resolving the distinction between authentic and artificial sound. It makes the distinction increasingly inadequate. The Disklavier is simultaneously acoustic and automated. The string quartet is simultaneously live and recorded. The organ is simultaneously monumental and breath-bound. Electronic interference generates pulses the machines themselves do not explicitly perform. Every category modifies another.
The nearly white sleeve condenses this entire argument into one perceptual object. It withholds contrast, the visual equivalent of reducing volume until the eye must increase its sensitivity. Shapes begin appearing only after attention has adjusted. The central form could be a person, tree, rock or shadow, and that uncertainty encourages the viewer to notice the process by which recognition is constructed.
The picture is not absent. It has been placed near the threshold of visibility.
Snow provides a useful comparison because it can conceal difference while also revealing minute disturbances. A landscape covered in white appears simplified, but tracks, depressions, shadows and changes in texture become unusually significant. Epistasis creates an equivalent listening environment. Its materials are limited enough that every alteration in density, breath, tuning and frequency acquires weight.
The white presentation also resists the obvious visual language of the album’s metal influence. There is no darkness, illegible logo, forest rendered through high contrast or theatrical image of death. Instead, darkness has been buried inside white. The black-metal and doom structures survive as harmonic pressure rather than costume.
This is more unsettling than straightforward visual aggression. A dark cover tells the viewer how to prepare emotionally. This one initially offers purity, silence and disappearance, then gradually reveals that the whiteness is crowded with difficult material.
Ruth Stofer’s design and the credited cover work attributed to Greenpointless NYC turn the package into another threshold between reproduction and perception. What may have begun as a photographic image becomes nearly abstract through the decisions of exposure, printing and contrast. Like the recordings, it retains evidence of an original acoustic or visual event while refusing transparent access to that event.
The 180-gram vinyl turns this nearly invisible design into a heavy physical object, another useful contradiction. The package looks weightless while the disc and music insist upon mass. Hallow Ground’s presentation does not try to sell experimental composition through explanatory diagrams or images of technology. It lets the listener encounter an object whose quiet surface contains pressure.
The credited musicians form an ensemble that extends well beyond the idea of a solo electronic album. Linnea Hällqvist and Knapp Brita Pettersson play violin; Maria Jonsson contributes viola; Natalia Goldmann and Johanna Niederbacher play cello; Mats Erlandsson and David Granström supply electric guitar; and Johannes Landgren and Fredrik Lundqvist perform organ. Maria W Horn composed, recorded and mixed the album, while Lawrence English mastered it.
These people are not decorative performers realizing an electronic composer’s private blueprint. Their physical limitations, tuning, breath and instrumental materials are built into the forms. The composition is exact, yet it needs differences among bodies in order to become itself.
Horn’s own path helps explain why the album refuses the usual divide between instrumental seriousness and electronic experimentation. She began by playing electric bass in punk and folk groups, then encountered an educational culture whose approved ideals of virtuosity made instrumental performance feel restrictive. An evening course in electroacoustic composition opened another route. The computer did not remove musicianship. It allowed her to redesign the conditions under which musicianship could occur.
That history remains audible in Epistasis. Punk’s suspicion of authorized technique survives inside highly disciplined composition. Doom and black metal enter the concert hall without requesting permission from conventional genre boundaries. Arvo Pärt’s tintinnabuli becomes a respiratory system shared by two organists. A computer-controlled piano does not demonstrate perfect obedience; it pushes perception toward instability.
The record is not ambient, although it can occupy a room with the physical subtlety often associated with ambient music. Ambient music is frequently expected to remain compatible with other activity. Epistasis demands a different bargain. Its changes may be gradual, but they continually alter the listener’s internal scale. Ignore them and the pieces seem nearly still. Attend closely and the same passages become crowded enough to disturb bodily orientation.
Nor is it simply modern classical music supplemented with electronics. The electronic material does not sit behind acoustic composition as atmosphere or production enhancement. It changes the ontology of the instruments. A recorded string part turns a quartet into an ensemble performing with another time. Interference tones cause an organ chord to generate rhythms that no performer controls. Code gives an upright piano capacities that alter what “performance” can mean.
Technology in this music is not a promise of escape from the body. It repeatedly leads back to the body: to breath, hearing thresholds, sensory overload, spatial location and the moment when attention can no longer separate all incoming events.
This makes Epistasis feel unusually relevant to a period in which human perception is increasingly shaped by machine systems. People interact daily with technologies designed to sort information, predict behavior and guide attention, often without understanding the full logic beneath the surface. Horn designs her own systems, listens to their answers and makes their operations perceptible. The machine is not hidden behind convenience. Its relationship with the person becomes the subject.
The album does not romanticize human imperfection against cold mechanical precision. Humans can behave rigidly; machines can generate surprise. The meaningful distinction lies in whether the relationship permits listening. Horn’s systems remain open to revision because she listens to what they produce rather than demanding that they confirm the original plan.
That responsiveness connects technological composition with the breathing organists and live quartet. Every part follows instructions, yet the final result cannot be reduced to instruction. Material answers back. A room emphasizes certain frequencies. A bow draws unexpected grain from a string. Two breaths refuse identical length. Feedback approaches a point the mix must either control or allow to bloom.
Epistasis is the art of those answers changing the question.
Its four pieces construct a sequence from accelerating machine pattern, through doubled string mass, into breath-governed organ circulation, and finally back to the machine. The route does not present a contest with a winner. Acoustic and electronic, human and artificial, ancient and modern repeatedly enter one another until their supposed oppositions become less interesting than the forms created between them.
The final silence leaves the listener in the same room but not quite at the same perceptual setting. Small background sounds may appear louder. A heating system, electrical hum or distant vehicle can briefly reveal its own interlocked cycles. The music has not added anything to the environment. It has changed which relationships the listener is capable of noticing.
The cover performs one last version of this transformation. After the hidden image has become visible, it is difficult to return to seeing an empty white square. Attention has modified the object permanently.
Nothing was added. The interaction changed what was already there.

