by Richard Zvonar

“Here we go loop de loop…”
-Johnny Thunder (1963)

August 22, 2002


Looping is a performance (or compositional) practice based on the repetition of recorded phrases. There are many ways to “loop” and there are many tools to loop with. It is a useful oversimplification to say that looping falls into two categories: 1) the sounds of a live performer are extended and multiplied by the use of delay processing and real-time sampling, 2) prerecorded sounds are played back in a repetitive way as part of a performance or recorded composition. In the present article we’ll focus mainly on category #1, since #2 is of necessity rather broad and sometimes ambiguous, intersecting with the worlds of techno dance music, remix, DJ turntablism, and other such scenes that deserve their own discussion.

Though notable exceptions exist, the majority of looping is done by solo performers as a means to create an ensemble effect without the involvement of other musicians (“solo ensemble” is a useful term). The simplest technical setup uses a recording device that allows delayed playback without interrupting the recording process – monitoring from the playback head of an analog tape recorder, for example. With tape, the greater the distance of the play head from the record head (and the slower the tape speed) the longer the delay. Digital delays follow a similar principle, but use a digital memory buffer instead of tape. Sound goes in one end (as digital samples) and comes out the other some time later. In technical terms this is called a “FIFO” stack “First In, First Out.” In acoustical terms the audible result is an echo effect; in musical terms it is a simple canon.

The usual next step is to feed the delayed output back to the input in order to generate multiple repetitions. The greater the amplitude level of this feedback path, the more “persistent” the repeating sound (e.g. with a feedback level of 100% the sound would repeat forever, at 90% it would die out gradually, at 110% – you don’t want to go there!). With shorter delay times the resulting effect is of multiple echoes, or reverberation. With longer delays (several seconds) the result can be anything from a gently pulsing drone, to an ostinato pattern, to a gradually evolving melodic or harmonic progression.

Another common approach is to latch the memory into an infinite repeat mode, so that the signal is no longer passing continuously through the delay memory but is being played back repeatedly. As you’d expect, a typical musical effect is of an insistent pulse or an ostinato. Technically speaking, this is more of a “sampling” mode than a “delay” mode, and it presents some interesting opportunities for variation of the looping sound material. For one thing, it is possible to vary the playback rate by speeding it up or slowing it down. In simpler delay processors this results in a simultaneous tempo and pitch change (just like varispeed tape playback). Another technique is to reset the delay “tap” so that the length of the looping memory segment can be varied. In some units it is possible to move both the start point and end point of the segment, creating a variety of rhythmic variations from the basic sound material. It is also possible to play through the sample buffer in reverse, creating backwards effects.

Contemporary looping devices and computer-based looping software offer these “classic” operating modes as well as many refinements. Some loopers now allow independent time scaling and pitch transposition; some even provide automated tempo detection for synchronization with the audio source. “Undo” functions are common, allowing the performer to “peel off” recorded takes in reverse order. Loopers allowing multiple simultaneous loops are becoming more common, as are nonvolitile memory and the use of memory cards for permanent storage of loops.


The musical ideas used in looping are as old as music itself: repetition and imitation, counterpoint and transformation. What defines contemporary looping is that it is based on the live use of recording technology, and it is natural that the first cases of delay- and loop-based musical experimentation date from the late 1940s when the first German tape recorders became available after World War II. Among the first American composers to embrace the possibilities of tape were Louis and Bebe Barron, who began working with tape loops and delay systems in 1948. Their 1952 score for the film “Bells of Atlantis” may have been the first public use of tape delay.

Part of the Barrons’ studio was a custom loop machine, and such special-purpose devices became increasingly common in electronic music studios throughout the 1950s. The studio of the French Radio (RTF) featured a device called the Morphophone, conceived by Pierre Schaeffer and designed by Francis Poullin. This device was based on a variable-speed turntable with a magnetic strip around its rim, outfitted with ten moveable playback heads. In 1955, Canadian inventor Hugh LeCaine began work on a series of tape loop playback instruments, the first of which could play six loops with variable speed controlled from an electronic keyboard. Later models featured up to 20 playback channels, and there was an effort develop a commercially-viable model.

Most of this early work was confined to private and istitutional electronic music studios, where the techniques were used as part of a compositional process that resulted in tape works for concert playback. The real watershed came at about 1960 when a younger generation of composer-performers began to experiment with live electronic music. Terry Riley was one of the first, using a pair of inexpensive Wollensack tape recorders to compose accompaniments for dance and theater. The 1960 Mescalin Mix (possibly the first psychedelic music) used one deck to play back an enormously long loop of source material, while the second deck was used to build up layers of sound by virtue of its sound-on-sound feature. Three years later, while in residence with a theater company in Paris, Riley began to use a technique that would lay the foundation for the next wave of looping and delay processing. His “Time-Lag Accumulator” consisted of a matched pair of tape decks with the tape threaded from the record deck to the playback deck in order to achieve very long delay times. By feeding the playback signal back into the input and regulating the level of this feedback path, a musical phrase could be repeated indefinately while new material was added to create a multilayered texture or complex counterpoint.

The French radio engineer who actually came up with this technical solution for Riley’s piece has long since been forgotton, but the technique itself lives on as the principal basis for most looping music. Riley soon began to use this system for his live keyboard and saxophone performances, and following his lead, many avant garde composers of the ’60s began threading tape through multiple decks. Probably the most active and inventive in this area was Pauline Oliveros, whose 1966 piece “I of IV” was one of the first commercially recorded works using long delay times and feedback techniques. Tape loops also became popular for live accompaniment at around this time. Jon Hassell started playing trumpet against loops of the vocal group the Hi-Los in 1960, and his later Fourth World Music incorporated loops drawn from many world music cultures.

Simultaneously with this underground exploration there was a burst of live-tape activity in popular music circles. Ever since Sam Phillips introduced slapback delay on an Elvis Presley recording in 1954, tape delay had been a staple of rock and roll recording practice. At first a tape deck would be dedicated to the task, but by 1960 a number of specially-designed tape delays began to proliferate. Such devices as the Meazzi Echomatic, Harris-Teller (later, Maestro) Echoplex, Watkins Copy-Cat, and the 1970s Roland Space Echo were based on a long tape loop, commonly with multiple playback heads and a variable speed tape transport. Some even offered a sound-on-sound function so that real-time overdubbing was possible. Tape speed manipulation and reverse playback became popular for cartoon voices and novelty records (Disney’s “Chip and Dale” and the David Saville Chipmunks). During the psychedelic era these techniques were explored by the Beatles, Jimi Hendrix, and others.

Ask any of the younger practitioners of looping and you’ll probably be told that guitarist Robert Fripp is the father of contemporary “loopism.” In most practical senses this is a reasonable assertion, because it was the Robert Fripp/Brian Eno recordings “No Pussyfooting” (1972) and “Evening Star” (1975) that introduced the practice to a wider public. The delay system, which Fripp later dubbed “Frippertronics,” was actually identical to Terry Riley’s 1963 “Time-Lag Accumulator”: two Revox tape decks with the tape threaded one to the other. Fripp perfected a personal approach to delay-based guitar performance that profoundly influenced the next generations. Live looping began to proliferate in both art-rock and jazz fusion circles.


There is one fundamental limitation to performing with analog tape delay systems – the time delay is constrained by a combination of the physical distance between record and playback head and the speed of the tape. Even with varispeed control of the transport motor and the addition of more playback heads the underlying phrase length of the music is locked to the current physical configuration and settings of the system. This began to change with the advent of analog and digital audio delay circuits in the early 1970s.

The first attempts at purely electronic performance delays were limited to very short looping delays of low sound quality. Though optimized for “flange” and echo effects, these processors often had just enough memory to allow the real-time capture of a short musical phrase. Like tape delays, this generation had to be preset to a particular tempo in order to capture a loop that would fit the pulse of the music. The problem persisted throughout the ’70s until the early ’80s, when the increased capacity and lower price of RAM chips allowed longer delay lines to be commercially viable.

At around this same time the newly-available microprocessors also allowed electronic instruments to be programmable, so that parameter settings could be stored and recalled. Finally, a new feature was introduced that virtually swept away the old problem of performing to a fixed delay time: tap tempo. By the simple act of clicking twice on a foot switch, a performer could now cause the delay processor to follow the live tempo rather than the other way around.

Delay processors were no longer simple “echo units,” and the concept of a “sampling delay” became common with such units as the Roland SDE-3000 (with the Playmate tap tempo feature), the Electro-Harmonix 16 Second Delay, and the high-end TC2290. The Lexicon PCM 42 was a particular favorite for serious loopers, having a programmable pulse output for synchronizing drum machines and sequencers, and being customizable with modifications such as expanded memory, sampling, and reverse playback. At this point delay times could exceed 60 seconds(!), though still at a high price. In addition, the early long-delay units were still limited to mono, and methods of synchronizing multiple units had yet to be perfected. This had a profound effect on the musical aesthetics of looping, since it was not yet possible to perform the sort of real-time multitracking that beat-oriented performance would require.

Much of the loop music of this period tended toward the “New Age” or “Space Music” genres. There were two basic approaches one could take to building up a composition in real time, and these both tended to influence this “floating” musical sensibility. With a long delay and a high feedback setting, la Time-Lag Accumulator or Frippertronics, one could record new phrases on top of earlier ones to build up layered textures, but the successive layers would be mixed together and couldn’t be “unmixed” later on. On the other hand, by using the delay unit in sampling (or “infinite repeat”) mode one could capture a phrase and play along with it as it repeated. By using multiple delay units one could even have multiple independent tracks which could be mixed in and out, but these independent loops would be asynchronous and would drift apart in time.

During the late 1980s Matthias Grob, a Swiss looper/guitarist with a technical background in digital electronics, grew frustrated with the musical limitations of the available tools. After unsuccessfully approaching several leading manufacturers with his ideas he decided to design and build his own looping device. In 1991 the Paradis Loop Delay was born. In addition to providing really long delay times, the Loop Delay introduced Multiply, Insert, and Undo functions. It also had advanced synchronization features that allowed multiple units to be configured either as multitrack groups or as beat-locked independent loops.

Soon after its introduction, the Loop Delay was joined in the marketplace by the Lexicon JamMan, but this device was short-lived. Still, the presence of two dedicated looping devices raised the profile of looping as a viable musical genre. Gibson Guitars look notice and formed a business partnership with Grob and his design team; the result was the Echoplex Digital Pro. This device has been on the market now for over ten years, branded first as an Oberheim and later as a Gibson product. It has a strong international following, but as a relatively pricey (over $1000) monophonic unit it is not to every looping musician’s taste. The recently introduced (and even more recently discontinued) Electrix Repeater fills the need for an affordable (under $500) four-track looper.