Thursday 4th October. Periods 3 + 4.Music Technology A2

A2 exam written question revision

‘The development of music technology’

•Must answer 1 question (choice of 2)•16 marks available (8% of A2)•Include 16 different points•Organise ideas in date order.•After planning, answer can be bullet points or prose

A2 exam written question revision

‘The development of music technology’Topics:

•Synthesisers•Drum machines•Samplers•Audio effects •audio processing – EQ / compression / expanders / gates / filters•MIDI•Recording media (tape / digital etc). Consumer media (Vinyl & MP3 etc)•Multi-track recording (Digital and Analogue)•Computer based recording – Cubase / Logic etc•Electric Guitars and Amplification Internet•Mixers•Digital Synthesis / FM / Additive / Wavetable / Sample based

Audio FX

….What do you know?

Audio FXIts better to spend a bit of time capturing or choosing an initial

sound carefully so you don’t have to spend a lot of time trying to

tidy up something badly recorded with FX and EQ.

Audio FX and EQ can be used creatively.

Audio FX• Reverb

• Delay

• Distortion

• Modulation • Chorus / Phase / Flange / Vibrato / Tremolo

Reverb• ‘Reverberation: - gradual decay of a sound due to

multiple echo's reflecting from the many surfaces of an acoustic environment.’

Reverb• Reverb was first created by placing a speaker in a room and

using a microphone to pick up the sound again including the reverb of the room. This is a natural echo chamber. 1950’s.

• Plate reverb. The exciter (Like a loudspeaker) plays the sound onto a metal plate and the vibrations are captured by the pick ups. Can be big and heavy (100’s Kilos). Dampening the plate shortens reverb time.

• http://www.youtube.com/watch?v=qFCFgvTU_Nw

Spring reverb. Like a plate reverb the sound is sent and picked up – this time through a metal spring. The length and tension (can be changed) alter the reverb characteristics. More practical than plate reverb.

Reverb• Digital reverb. Reverb is created with a very large number of very small audio delays

varying in size and decay along with dampening (filtering).

• Varying the amount, decay, feedback, pre-delay (the time it takes to hear the first reverb or reflection can change the characteristics and different rooms can be ‘modelled’.

• http://www.youtube.com/watch?v=rKgKO0sBsaU&feature=share&list=PL1DB8C6FB02C86E84

• http://www.youtube.com/watch?v=9qS2DiF0mR4&feature=fvwrel

Delay• Or echo was first created in mid to late 1940s, recording

engineers and experimental musicians such as Les Paul began manipulating reel-to-reel recording tape to create echo effects and unusual, futuristic sounds.

• Delay units based on analogue tape became available from the 1950’s. The speed of the tape and position between the record and playback heads determined the delay time.

• EP-2 Tube Echoplex• http://www.youtube.com/watch?v=dB

HOvEVHlew

Digital Delay• Works by ‘sampling’ the input audio then storing the

audio digitally in a buffer (memory) and playing it back. The bigger the buffer (memory) the longer the delay.

• Developed in the late ‘70s. First digital delay pedal by Boss in 1984.

• ‘…delay units evolved into digital reverb units and on to digital multieffects units capable of more sophisticated effects than pure delay, such as reverb and Audio timescale-pitch modification effects.’

• Software delay plugins work in the same principle but offer more flexibility on shaping the sound (eg filters and eq).

• Locking the delay time to the tempo (or a division / multiple of the tempo) is usually used in a track.

Distortion• The distortion effect on audio is produced by overdriving an

amplifier so that it clips the audio.

• ‘…clipping’ audio is a process that produces frequencies not originally present in the audio signal. These frequencies can either be "harmonic", meaning they are whole number multiples of the signal's original frequencies, or "inharmonic", meaning dissonant odd-order overtones…’

• Originally used in the early 1950’s by turning up valve guitar amps until they started clipping the sound.

• 1961 Maestro Fuzztone FZ1• http://www.youtube.com/watch?v=lEkTs

KfI3-4&feature=related

Creating Distortion• Originally created by overdriving (guitar) amps. A characteristic of

the components used (valves) when the input signal went beyond the threshold they were designed to cope with.

• Distortion also created in ‘solid state’ electronics (transistors / op amps). And by outputting too much power to a loud speaker.

1978 Boss DS-1 Distortion pedal using solid state electronics.

Distortion can be created digitally (hardware or software) by modelling analogue distortion. This is sometimes considered not as sonically accurate as traditional analogue distortion (especially by guitarists).

Phaser • Created by delaying and audio signal by small amounts

and then mixing this with the dry signal.• The delayed signal will have a different ‘phase’ to the

original signal. • Certain frequencies of the original signal will be

reinforced or cancelled depending on the delay time.• http://www.youtube.com/watch?v=gYF2h5ry3kY

Flanger• Flangers use a similar method to

phasers but tend to sound more pronounced whereas phasers tend to sound more subtle.

• Originally created by playing back the same audio on 2 tape machines and slightly making them go out of sync.

• http://www.youtube.com/watch?v=DO7IEqWqSiI&feature=related

Chorus• ‘ ..taking an audio signal and mixing it with

one or more delayed, pitch-modulated copies of itself. The pitch of the added

voices is typically modulated by an LFO…’

• Created by similar method to phase / flange but harmonically spaced notches

and peaks in the frequency spectrum are manipulated to modulate more tightly,

rather than shifted to swoosh broadly up and down like a flanger.

• Chorus is different to Phase / Flange as it requires a pitch altered signal to be mixed with the input signal to create the effect. http://www.youtube.com/watch?v=r9B-

IYmtf1w

Vibrato / Tremelo• Vibrato:• ‘. regular,

pulsating change of pitch…. characterised in terms of two factors: the amount of pitch variation and the speed..’

• Tremelo:• ‘..regular,

pulsating change of volume…. characterised in terms of two factors: the amount of modulation variation and the speed..’

Vibrato / Tremelo• Leslie Speaker creates:

Vibrato (change in pitch) by ‘stretching’ and ‘shrinking’ audio and this changes the frequency / pitch. Doppler effect.

• Tremolo (change in loudness) is also created because the sound gets louder as the speaker is pointing at the listener and then quieter as it rotates away.

• http://www.youtube.com/watch?v=quE0ElIAwZE&feature=related

• Associated with Hammond organs. Invented by Don Leslie in early 1940s because he didn’t like the sound his Hammond organ made.

• http://www.youtube.com/watch?v=O_l5fY1QoYo

Homework• Find some popular music tracks that feature prominently these audio effects:

• Delay or Echo• Reverb (natural or processed)• Phasing or Flanging• Chorus or Vibrato• Tremolo

• You could choose 5 different tracks feat. 1 effect each or 1 track might feature more than 1 effect etc.

• Write down the artist and track titles along with the effect names and time(s) in the track they appear. Further study - Do you know how the effect was created in that track (what specific equipment) ?

• *** Further study – who were the pioneers of effects. For example which guitarists first used distortion and (slap back) echo (delay)?