A-Level Music Technology - Edexcel

Automatic Double Tracking

A tape delay that is used to simulate double tracking using only one recording. Also known as ADT.

Aliasing

An issue that occurs when the sampling rate (in analogue to digi conversion) has been set too low.

Analogue

Equipment that is 'real' and not digital. A continually changing voltage or current that represents a sound (sound is analogous to the original sound wave).

Anechoic Chamber

A room, insulated from any external vibrations or noise ( no reverb and silent)

Artificial Harmonics

playing technique on guitar or string inst, Fretting the note with hand simultaneously touching a node point to create a harmonic and plucking the string.

Attack

the time taken for a sound to reach its max amplitude // time taken for a processor to act after the signal has passed a set threshold (e.g compressor)

Bit Depth

the number of bits available to describe a number. the more bits the more resolution. a lower bit depth increases hiss and grainy audio because the steps between one value and another become audible

Centre Frequency

The frequency at which a band-pass or notch filter will have the maximum effect

Clipping

Exceeding the max volume specification of a given device. Also known as peaking or distortion, when digital this is unpleasant. On analogue equipment, this is sometimes acceptable or desirable.

Cut-off Frequency

The value at which a filter has an audible effect on the frequency range. Normally applied to a LPF or HPF.

CV/Gate

Control Voltage used in analog systems to control external devices from a sequencer. CV controls the pitch and the gate controls the note on/off

Delay

Effect in which the original signal is repeated one or more times.

Double-Tracking

Recording (overdubbing) a nearly identical version of an existing track on a separate track, which is played back at the same time (layered) to create thicker sound

Drawbars

Controls used to mix the waveform ratios in a tone wheel organ (Hammond B-3)

Echo Chamber

A large enclosed space with hard surfaces used to create echoes and reverb

Echoplex

A tape delay unit used from the 1960s

Fairlight CMI

Early digital sampler used in a lot of 1970s songs

Feedback

When the sound produced from a loudspeaker is picked up by a microphone or guitar pickup and amplified further and passed through speaker again forming a loop. And crescendos in an audible frequency

Frequency Modulation (FM)

When the frequency of a carrier signal is varied in accordance with a modulating signal, the carrier and the modulating signal are both in the audible frequency range creating a complex waveform

FX

Processes applied to a signal to alter its sound in some way - short for Effects.

Gain

Stage of a pre-amp that boosts the level of a signal at the beginning of the signal path, Commonly applied to any volume boost in the signal path

128

How many voices were available in the GM (General MIDI) sound set?

Gigasampler

Software sampler. In the 1990s and 2000s the increases in computer power and memory capacity have made it possible to develop software applications that provide the same capabilities as hardware-based units.

Glitching

Occurs when audible unwanted sounds are introduced to a signal, often done on purpose.

Leslie Speaker

A rotating speaker, used with a hammond organ, which creates a phaser effect through doppler effect (tremolo/vibrato)

Lo-Fi

A recording that is deliberately noisy and lacking full frequency range (low bit). Low Fidelity.

Mellotron

An early, tape-based sampling keyboard

MIDI

Musical Instrument Digital Interface:
An 8-bit computer language developed to allow electronic instruments to communicate with each other

Modular Synth

A synth made up of separate sections (such as OSC, Filters, and envelope generators) linked using signal cables

Mono

A signal carried on one channel

Musique Concrete

Music created by capturing/manipulating and combining naturally occurring and artificial sounds onto tape (traffic, weather etc...)

Normalising

The process of boosting an audio signal so that the loudest peak registers as 0dB

Output Gain

Signal boost after processing

Palm-Muting

A guitar playing technique, the notes are muted by placing the heel of the hand lightly against both the strings and the bridge

Pan

The placement of a sound in the stereo field

Q

The range of freq. affected by a filter (a measure of resonance of a filter)

Regeneration

A parameter on flangers used to set the amount of the affected signal sent back into the input

Release (ADSR)

the time taken for a sound to decay after the note has been released

Rhythmicon

Invented in 1931, this was the first electronic drum machine.

Rumble Filter

Another word for High Pass Filter (or HPF), used to eliminate unwanted low frequencies such as footsteps and traffic, without affecting the desired sound.

Sample

A short, prerecorded sound used in the context of music

Sample Rate

The number of times an analog to digital converter samples the signal every second, measured in Hz (e.g 44.1kHz)

Sampler

Device used to store and playback samples (and often record them)

Scratching

A DJ technique. Manually rotating the turntable platter while the needle is in contact with the vinyl creating a scratching sound, and pitch bends / time changes.

Self-Oscillation

occurs when the Q has been set so high that a filter will generate a tone its own

Sequencer

Device used to facilitate the input, editing and playback of MIDI data.

Signal-to-noise ratio

The level of wanted signal compared to the level of unwanted noise

Spot Mic

The technique of focussing a mic on an individual or a small group within a larger group that is being captured by other mics, to allow for selective boosting of the individual or group

Stereo

A Signal carried on two channels (left/right) to represent a sound image as it might be picked up by 2 ears

Stompbox

A floor mounted guitar effects unit (pedal)

Tape Saturation

The point at which the magnetic particles on a tape will no longer respond to magnetic force, this has a subtle distortion effect that some artists find effective.

Theremin

An early synth played by mean of moving the hands in proximity to one or two ariels

Threshold

A preset loudness point which once passed causes a process to occur, (compressors / gate)

Tonewheel

In an organ, a series of discs rotated by a motor in proximity to an electromagnetic pickup.

Tremolo Arm

A rod attached to the bridge of a guitar that enables the player to change the tension of the string, altering the pitch of the sounding note. Also known as a whammy bar.

Turntablism

The art of using one or more turntables as an instrument, combined with a mixer and cross fader to manipulate and mix sounds.

Valve Amplifier

Amps that use vacuum tubes (valves) instead of transistors in the pre-amp and or power amp stages. Often produces a warmer sound

Violining

Guitar playing technique where a note is struck while the volume control is at its lowest value and is then immediately turned up. This results in the loss of the attack portion of noise.

Virtual Modelling

Creating a software version of a hardware device.

Granular synthesis

A type of synthesis in which audio samples are not played back conventionally, but are instead split into small pieces of around 1 to 50 ms. These small pieces are called grains.

Additive synthesis

A sound synthesis technique that creates timbre by adding sine waves together.

Subtractive Synthesis

The process of creating a new sound by filtering and shaping a raw, harmonically complex waveform.

Dynamic Microphone

Rugged, durable mic; uses small coil that moves within a magnetic field to produce a signal

Condenser Microphone

Higher quality, more sensitive mic requiring power; uses a diaphragm that moves against a back plate to produce a signal

Ribbon Microphone

Extremely sensitive, used only in audio booths; uses a small ribbon (rather than a coil) to produce sound

Phantom Power

Often seen on audio equipment as +48V. Provides the fixed charge for a condenser microphone

Polar Pattern

A visual reference to how well a microphone picks up sound within 360° of its central axis.

Cardioid

Heart-shaped pickup pattern of a unidirectional microphone.

Hypercardioid

Very narrow unidirectional pickup pattern with a long reach. The mic is also sensitive to sounds coming directly from the back.

Figure of 8

A microphone polar pattern in which the mic is (nearly) equally sensitive to sounds picked up from front and back, but not sensitive to sounds on the sides. The pattern is also known as bi-directional.

Frequency Response

A measure of an audio system's or microphone's ability to reproduce a range of frequencies with the same relative loudness; usually represented by a graph.

Transient Response

The measure of how quickly a mic's diaphragm will react when it is hit by an acoustic wavefront.

Impedance

The acoustic resistance to sound travelling in a medium - can be labelled as Lo-Z or Hi-Z.

proximity effect

increase in LF response when placed near sound source; typical of directional mics

Hiss

A high-frequency noise problem inherent in the recording process, often associated with tape recordings.

Phasing issues

Issue caused by sound waves that do not line up, which can cause destructive interference or even cancel out the sound wave

DI

Direct input or direct injection

XY

Also known as a coincident pair, this mic technique combines two cardioid microphones right next to each other, to create a stereo image with good mono compatibility

AB

Also known as a spaced pair, this mic technique uses two mics that are placed side by side, which adds a wide stereo image. This technique must respect the 3:1 ratio in order to avoid phase issues.

Mid-side

This mic technique uses a cardioid and a figure of 8 mic, set up at 90 degress to one another.

ADSR Envelope

A method for controlling a synthesizer through Attack Decay Sustain Release times in ms.

Sine Wave

A pure tone, a wave whose source vibrates with simple harmonic motion

Triangle Wave

A symmetrical shaped wave containing odd harmonics only. Slightly harsher than a sine wave, it has a flute-like sound good for pads.

Sawtooth Wave

A sound wave which contains every harmonic. Each harmonic is attenuated by 1/2, 1/3, 1/4, 1/5... in amplitude. It has an even and edgy sound, often used for strings, basses and dance leads.

Square Wave

A symmetrical waveform which contain a series of odd harmonics. Sounds hollow and woody, good for clarinet, oboes and bass sounds.

Pulse Wave

An asymmetrical waveform with a variable pulse width. It is quite nasal sounding and good for recreating reed instruments and basses.

Noise

All frequencies at an equal amplitude. This can be used to simulate wind or percussive sounds like cymbals, and can be filtered to create a sweeping effect.

Portamento

Also known as glide, this controls the amount of time it takes to slide between two overlapping notes.

Resonance

Often used on a synthesiser filter to add a characteristic narrow boost of frequencies around the cutoff. High amounts can lead to self-oscillation.

Low Frequency Oscillator

This oscillator is too deep for us to hear it (usually between 0.5 and 15Hz), so it is normally applied to a signal to modulate it in some way, such as vibrato or modulating the cutoff frequency. Also known as LFO.

Zero Crossing Point

The point at which a signal waveform crosses from being positive to negative or vice versa. It is important to cut samples at this point to avoid creating a click.

Quantise

This tool moves the timing of the beginning of a note to the nearest grid division: a note length, beat or bar.

Ratio

In compression, the amount of input:output volume; this is how much the compressor will reduce the signal by once the signal is above the threshold.

Parametric EQ

An equalizer with separate controls for frequency, bandwidth and cut/boost.

Convolution Reverb

This type of reverb is an effect that takes an impulse response (IR) recorded in a space and uses this to impart this ambience on audio signals. It reproduces a real reverb through an algorithm and was pioneered by Sony in the late 1990s.

Wavetable Synthesis

A method of generating waveforms through lookup tables. Many software synthesizers use
synthesis where these digitized waveforms are organized in a bank or table, accessed through a sequencer.

VCO

Voltage Controlled Oscillator

VCF

Voltage Controlled Filter

VCA

Voltage Controlled Amplifier

Plosive

A short burst of sound made when you say a word containing the letters b, d, g, k, p or t