Audio signal processing is a subfield of signal processing that is concerned with the electronic manipulation of audio signals. Audio signals are electronic representations of sound waves—longitudinal waves which travel through air, consisting of compressions and rarefactions. The energy contained in audio signals or sound power level is typically measured in decibels. As audio signals may be represented in either digital or analog format, processing may occur in either domain. Analog processors operate directly on the electrical signal, while digital processors operate mathematically on its digital representation.
An effects unit, effects processor, or effects pedal is an electronic device that alters the sound of a musical instrument or other audio source through audio signal processing.
CV/gate is an analog method of controlling synthesizers, drum machines, and similar equipment with external sequencers. The control voltage typically controls pitch and the gate signal controls note on-off.
Boss is a manufacturer of effects pedals for electric guitar and bass guitar. It is a division of the Roland Corporation, a Japanese manufacturer that specializes in musical equipment and accessories. For many years Boss has manufactured a wide range of products related to effects processing for guitars, including "compact" and "twin" effects pedals, multi-effect pedals, electronic tuners and pedal boards. In more recent times, Boss expanded their product range by including digital studios, rhythm machines, samplers and other electronic music equipment. They also are now manufacturing solid-state amplifiers and speaker heads such as the Waza and the Katana. Both feature multi-effects units meant to emulate Boss' classic effects pedals.
The Moog Taurus is a foot-operated analog synthesizer designed and manufactured by Moog Music. It was originally conceived as a part of the Constellation series of synthesizers. The initial Taurus I was manufactured from 1975 to 1981, followed by a less popular redesign, Taurus II, followed from 1981 to 1983. Instead of a conventional keyboard, the Taurus uses an organ-style pedal board similar to the pedal keyboard of a spinet organ. This control method was chosen because the Taurus was intended to be played by foot while the player's hands played one or more keyboards, although it was often used by guitarists. While the original Taurus featured its own synthesis engine, the Taurus II was essentially the same as the Moog Rogue. In 2010, Moog issued the Moog Taurus III which closely emulates the analog circuitry of the Taurus I, in addition to adding some modern features.
Elektron is a Swedish developer and manufacturer of musical instruments founded in 1998, as well as having its headquarters, R&D and production in Gothenburg, Sweden. They produce mainly electronic musical instruments, but have also made effects units and software. Since 2012, there have been branch offices in Los Angeles and in Tokyo.
Moog Music Inc. is an American synthesizer company based in Asheville, North Carolina. It was founded in 1953 as R. A. Moog Co. by Robert Moog and his father and was renamed Moog Music in 1972. Its early instruments included the Moog synthesizer, followed by the Minimoog in 1970, both of which were highly influential electronic instruments.
An expression pedal is an important control found on many musical instruments including organs, electronic keyboards, and pedal steel guitar. The musician uses the pedal to control different aspects of the sound, commonly volume. Separate expression pedals can often be added to a guitar amplifier or effects unit and used to control many different aspects of the tone.
A phaser is an electronic sound processor used to filter a signal by creating a series of peaks and troughs in the frequency spectrum. The position of the peaks and troughs of the waveform being affected is typically modulated by an internal low-frequency oscillator so that they vary over time, creating a sweeping effect.
Electro-Harmonix is a New York City-based company that makes electronic audio processors and sells rebranded vacuum tubes. The company was founded by Mike Matthews in 1968. It is best known for a series of guitar effects pedals introduced in the 1970s and 1990s. EHX also made a line of guitars in the 1970s.
Moogerfooger is the trademark for a series of analog effects pedals manufactured by Moog Music. There are currently eight different pedals produced; however, one of these models is designed for processing control voltages rather than audio signal. A sixth model, the Analog Delay, was released in a limited edition of 1000 units and has become a collector's item. Moog Music announced on August 28, 2018, that the Moogerfooger, CP-251, Minifooger, Voyager synthesizers, and some other product lines were being built using the remaining parts on hand and discontinued thereafter.
Chorus is an audio effect that occurs when individual sounds with approximately the same time, and very similar pitches, converge. While similar sounds coming from multiple sources can occur naturally, as in the case of a choir or string orchestra, it can also be simulated using an electronic effects unit or signal processing device.
Musitronics, often shortened to Mu-tron, was a manufacturer of electronic musical effects active in the 1970s. Founded by Mike Beigel and Aaron Newman, the company's products provided filtering and processing effects and were derived from synthesizer components. The company was known for producing high-quality products with many user-adjustable parameters, but high production costs and a failed product line, the Gizmotron, caused its downfall.
In computer music and professional audio creation, a DirectX plugin is a software processing component that can be loaded as a plugin into host applications to allow real-time processing, audio effects, mixing audio or act as virtual synthesizers. DirectX plugins allow the replacement of traditional recording studio hardware and rack units used in professional studios with software-based counterparts that can be connected together in a modular way. This allows host manufacturers to focus on the conviviality and efficiency of their products while specialized manufacturers can focus on the digital signal processing aspect. For example, there are plugins for effects boxes, such as reverbs and delays, effects pedals, like guitar distortion, flange and chorus, and for mixing and mastering processors such as compressors, limiters, exciters, sub bass enhancers, stereo imagers and many more.
The Univox Super-Fuzz was a fuzzbox produced by the Univox company, primarily for use with the electric guitar or bass.
Multivox was an American-based synthesizer company since the mid-1970s until the 1980s. Originally it was founded in the mid-1940s as the guitar and amplifier manufacturing subsidiary of Peter Sorkin Music Company, a New York-based retailer/wholesaler. Then eventually it established separate corporate identity, and after the close of Sorkin Music in the mid-1970s, it continued in existence for fourteen years, according to the Blue Book of Guitar Values. In addition to synthesizers, the company marketed several effects pedals. These included the Big Jam series guitar effects line.
The Korg PS-3300 is a polyphonic analog synthesizer, produced by Korg between 1977 and 1981.
Source Audio is a guitar effects pedal company based near Boston, Massachusetts. They produce modular effects pedals for electric guitar and bass, such as the Nemesis Delay, Ventris Dual Reverb, and Collider Delay+Reverb, as well as the C4 Synth, a modular rack synthesizer in pedal format, the Aftershock Bass Distortion, and the EQ2, a 10-band parametric equalizer with a plug-in style desktop interface. They are also the creators of the Hot Hand Wireless Effects Controller, a device worn around the finger that uses an accelerometer to send expression signal to an effect like an envelope filter. Source Audio mainly uses DSP to create their effects, and are known to program their own processor chips.
Keeley Electronics is an American manufacturer of effect units for electric guitars. The company, founded by Robert Keeley and operating from Oklahoma City, Oklahoma, started with the Keeley Compressor pedal along with modifications for effects by Boss and Ibanez.
Vintage musical equipment is older music gear, including instruments, amplifiers and speakers, sound recording equipment and effects pedals, sought after, maintained and used by record producers, audio engineers and musicians who are interested in historical music genres. While any piece of equipment of sufficient age can be considered vintage, in the 2010s the term is typically applied to instruments and gear from the 1970s and earlier. Guitars, amps, pedals, electric keyboards, sound recording equipment from the 1950s to 1970s are particularly sought. Musical equipment from the 1940s and prior eras is often expensive, and sought out mainly by museums or collectors.
