Music Technology Guide



AS REVISION PAGE

Topics to explore for April Mock

Click on links below to revise topic

Effects: Reverb

Reverb is the natural sound of a room/acoustic space.

Prior to the 1950s, the earliest form of reverb were natural recordings of rooms at the time of recording which could not be removed afterwards.

Many reverbs were to follow...

Effects: Delay

An effect in which the original signal is repeated one or more times. There is normally a progressive decrease in the volume and sometimes the high-frequency content with each repeat.

Famous Delays

  • 1950s: Analogue Tape Delay / Slap Back

  • 1970s: Early Digital Delay, Bucket Brigade Device

  • 1980s: Digital Delays, Time / Sync / Stereo TAP delay (foot tap in time with the song)

  • 1990s: VST algorithm based software plugins

    • Main Delay Parameters

  • Delay Time: distance between each repeat measured in note lengths i.e Crotchets 1/4s, Quavers 1/8s, Semi-Quavers 1/16s etc

  • Feedback: controls the amount of repeats

  • Dry/Wet: the volume balance between the original signal and repated affected signal

    • Application of Delays

  • Delay in the 1950s and especially the 1960s used a recognisable analogue slap back effect

  • 1980s digital productions began to explore more intricate delay patterns with use of Stereo bouncing Left to Right as can be heard in the above audio example

  • Modern EDM (Electronic Dance Music) uses tight time synced delay, in sync with Semi-Quavers(1/16th notes), Stereo Delay, with a high WET level in which the repeats are gradually filtered (LPF or HPF)

    • Stereo Field

    For this question, you must state which section of the Stereo Field an instrument is placed, which will be LEFT / CENTRE / RIGHT

    As a general rule....this pic says it all

  • Centre: Kick, Bass, Snare, Main Vocals and any prominent lead acting as a focal point when no Vocals

  • Left / Right: Synths, Guitars, Toms, Cymbals

    • Check your headphones are placed on correctly







    Multitracking

    Multitracking is the process of recording audio alongside previously recorded audio (interestingly invented by guitar pioneer Les Paul)

    It was invented in the 1950s, but became common practice in professional studios in the 1960s

    An example would be a Vocalist recording alongside their own previously recorded vocal take; this process is known as DOUBLE TRACKING

    Checkout the 3 multitrack machines on the right

    • Left machine: 2 tracks, early 1960s

    • Middle machine: 4 tracks, mid 1960s

    • Right machine: 16 tracks, late 1960s



    Synchronisation

    Synchronisation is how a band plays and records in time with one another

    This can be achieved by...

    • Playing Live

    • Using a click track

    • Using a Guide track

    • Ensuring the band is well rehearsed


      • If the tempo of a track is to increase, the CLICK TRACK would be automated to speed up



    Compression

    Compression is used to control the Dynamic Range; the Volume of an audio signal

    When an audio signal's VOLUME (dB) passes a specified THRESHOLD (dB), the compressor will reduce the output RATIO by a designated amount (i.e 2:1)

    Compression is used...

    • To control the volume of an individual instrument

    • To control the volume of a whole track known as LIMITING

    • Creatively to give a sound more 'punch'

    • Creatively for rhythmic effects such as side chain compression to create a pulse



    Recording Technology by Decade

    Since the first recording device in 1877, technology has evolved rapidly; acoustic, electric, magnetic to digital

    • The Acoustic era (1877–1925); Large horn collects air and via a stylus imprints air pressure of the sound waves onto a phonograph cylinder coated in wax

    • The Electrical era (1925–1945); Microphone captures audio still physically inscribed into a wax master disc then in the early 1940s on to Vinyl

    • The Magnetic era (1945–1975); Audio routed through mixing desk and onto magnetic tape

    • The Digital era (1975–present); Audio converted into digital binary code (0s and 1s) via an ADC (Analogue to Digital Convertor) and stored on a hard drive. All in one Multitrack Digital Recorders were very popular in 1990s





    Mixing

    Mixing is the process of using numerous audio tools to blend and balance multiple recorded instruments resulting in a cohesive Master track

    The 5 main elements of Mixing are...

    • Balance: Volume / Level (dB)

    • EQ:(Hz) used to shape timbres to sit well with other instruments in the same frequency range

    • Panning: Creating width by placing in the stereo field

    • Effects: Reverb, Delay to create Depth

    • Dynamics: Control the volume





    Quantization

    Quantization is a function used to correct the timing of MIDI notes in which you use time values as its settings. You are effectively 'snapping' your MIDI notes to the nearest chosen time value.

    • Semibreve = 4 beats = 1

    • Minim = 2 beats = 1/2

    • Crotchet = 1 beat = 1/4

    • Quaver = 1/2 beat = 1/8

    • Semi-Quaver = 1/4 beat = 1/16

      • Most intricate drum patterns will be quantized to 1/16th like the one on the right





    Sampling

    Sampling is the reuse of a portion (or sample) of a sound recording in another recording. A Sampler is a device used to capture, edit, manipulate, store and playback samples.

    Samples can be manipulated as follows...

    • Looped Copied and pasted or assigned to a MIDI note and triggered

    • Layered

    • Re-Pitched

    • Sped up

    • Slowed down

    Sampling can be identified by Identical phrasing, Identical articulation, Identical volume



    Sequencing

    Sequencing allows a producer to program a performance often using MIDI to trigger samples

    Sequencing techniques...

    • Various Quantization

    • Different Samples and Rhythms for Verse/Chorus

    • Varied Loop Lengths

    • Scratching samples

    • Pauses/dropping out/missed beats

    • Rhythmic fills/transitions on kick/snare/open hi-hat



    Microphone Techniques

    There are many considerations when recording various sound sources

    • Single Mic or Stereo Pair: MONO or STEREO recording

    • Condensor: Wide frequency response

    • Polar Pattern: Cardioid/directional is more focussed

    • Direction: General rule 9-12 inches from sound source i.e where hammers hit the strings of a piano

      • In the 1960s, Microphones will still limited with a poor/low frequency response





    Bouncing Down Technique

    The Bouncing Down technique was a widely used process used in the 1960s when recording devices were limited to 4 tracks.

    For example, engineers would record 4 individual tracks such as Kick, Snare and Overheads then....

    • Balance the levels / volume

    • Apply Effects and EQ

    • Adjust gain to ensure a high SIGNAL to NOISE Ratio (SNR)

    • then BOUNCE DOWN this MASTER drum output to one single track

    • freeing up the remaining channels for further recording

      • However, this came with limitations...

    • High frequencies are lost with each bounce

    • Additional noise is added with each bounce

    • This process cannot be undone/reversed



    EQ

    Equalisation is an audio processing tool used to shape the timbre of a sound. Think of it like a chisel being used to shape a sculpture; EQ is used to cut or boost frequencies.

    • 1960s; Analogue EQ was limited, with poor frequency range resulting in flat recordings

    • 1980s; Modern Digital EQ allows for much greater control with accessibility to a wider frequency range, for example higher frequencies can be boosted

      • EQ use filters to adjust the timbre by adjusting...

    • Frequency (Hz)

    • Cut or Boosting Volume (dB)

    • Setting Bandwidth (Q); how many surrounding frequencies are affected

    Low / High Pass Filter

    Filters are often used in a creative way, especially in genres such as Dance Music

    In the video, White Noise (every frequency) has been generated and two types of filters have been automated to SWEEP the frequency range

    • The first Filter is a LPF, Low Pass Filter; it only allows the LOW frequencies through, gradually SWEEPING DOWN the frequency spectrum removing high frequencies as it descends

    • The second Filter is a HPF, High Pass Filter; it only allows the HIGH frequencies through, gradually SWEEPING UP the frequency spectrum removing low frequencies as it ascends







    Electronic Dance Music

    Main Production Techniques of EDM

    • FX: Long Reverb / Delay to provide space/depth and create an airy/dream like quality mix

    • EQ: Bright Vocals helps cut through the mix

    • EQ: Synth Pads fill out low mid range, not many high frequencies

    • Kick: Prominent in low frequencies

    • Drums: Build in volume then Drop, often become more intricate patterns to build suspense

    • Dynamics: Heavy Compression to make instruments sound 'punchy' and more prominent