Synthesis

Question 1

What is a synthesiser?

Answer 1

An instrument that electronically creates sound.

Question 2

What does additive synthesis do?

Answer 2

Combines basic sine waves from the harmonic series.

Question 3

How is additive synthesis perceived?

Answer 3

Fundamental note is heard as a pitch, the resonating notes as harmonics

Question 4

What happens to harmonics as they go higher?

Answer 4

They get quieter.

Question 5

Give an example of an instrument that uses additive synthesis. Give its date.

Answer 5

Hammond B3 organ. 1954

Question 6

What is subtractive synthesis?

Answer 6

An oscillator creates harmonically rich waveform so that filters can be applied to them.

Question 7

How does FM synthesis work?

Answer 7

A carrier frequency holds the pitch or fundamental frequency. The modulation frequency alters the carrier frequency with modulation.

Question 8

How is a waveform produced?

Answer 8

Voltage Controlled Oscillator (VCO)

Question 9

What is a sine wave?

Answer 9

Simple regular wave with pure sound.

Question 10

Why isn’t a sine wave used in subtractive synthesis?

Answer 10

If filtered there would be nothing left

Question 11

What does a sawtooth wave sound like? What is it ideal for?

Answer 11

Edgy sound, ideal for string sounds.

Question 12

What is a triangle wave used for?

Answer 12

Quiet harmonics

Question 13

What sound does a square wave make? What does it emphasise on?

Answer 13

Hollow sound; emphasises on odd numbered harmonics

Question 14

What is a pulse wave?

Answer 14

Narrow square wave with variable pulse width.

Question 15

What is white noise?

Answer 15

Hissing sound containing all the frequencies.

Question 16

What is pink noise?

Answer 16

Rumbling sound with emphasis on lower frequencies.

Question 17

What are the three main types of VCF?

Answer 17

Low- pass
Hi - pass
Band - pass

Question 18

What is an envelope shaper?

Answer 18

ADSR: attack, decay, sustain, release.

Question 19

What is an envelope shaper normally applied to?

Answer 19

Amplitude (VCA), can also include VCF (filter) and VCO (pitch)

Question 20

What is Attack on ADSR?

Answer 20

How quickly the sound reaches full volume after being triggered.

Question 21

What is Decay on ADSR?

Answer 21

How quickly sound drops to sustain level after initial peak.

Question 22

What is Sustain on ADSR?

Answer 22

“Constant” volume sound takes after decay until note is released.

Question 23

What is release on ADSR?

Answer 23

How quickly sound fades when note ends.

Question 24

How is modulation achieved?

Answer 24

LFO

Question 25

How can a vibrato effect be created?

Answer 25

Moderately fast time and short pitch range applied to VCO.

VCO x LFO

Question 26

How is a tremolo effect created?

Answer 26

VCA x LFO

Question 27

How is a Wah effect created?

Answer 27

VCF x LFO

Question 28

What is De-tuning? What result does it create?

Answer 28

Combining one waveform with another which is set at a slightly different pitch, creates an enriched result.

Question 29

What is Portamento?

Answer 29

Pitch slide

Question 30

What is an arpeggiator?

Answer 30

Built - in sequencer to create patterns of notes.

Question 31

What does pink or white noise do when added?

Answer 31

Mixed with a musical waveform creates more gritty sounds.