Music & Audio Advice Synthesis and Sound Design Questions and Answers 1

Question 1

In subtractive synthesis, what is the primary function of a low-pass filter?

Accepted Answer

To remove high-frequency content above the cutoff point.

Answer

Subtractive synthesis starts with a harmonically rich waveform (like a sawtooth or square wave) and shapes its timbre by removing, or subtracting, parts of the frequency spectrum. A low-pass filter is the most common tool for this, allowing low frequencies to pass through while attenuating (cutting) high frequencies above its set cutoff frequency.

Question 2

A sound designer is creating a lush, atmospheric pad sound. They want the sound to fade in slowly when a key is pressed, remain at a steady volume while the key is held, and then fade out gradually after the key is released. Which ADSR envelope settings are most appropriate?

Accepted Answer

Slow Attack, High Sustain, Long Release

Answer

To achieve a slow fade-in, a long/slow Attack time is needed. To ensure the sound remains at a consistent, audible level while the note is held, a high Sustain level is required. For a gradual fade-out after the key is let go, a long/slow Release time is necessary.

Question 3

Which of the following describes the most common method for creating a classic vibrato effect on a synthesizer?

Accepted Answer

Routing a low-frequency oscillator (LFO) to modulate the oscillator's pitch.

Answer

Vibrato is a periodic, subtle variation in pitch. A Low-Frequency Oscillator (LFO) produces a cyclical control signal at a sub-audible rate. By routing this LFO to the main sound-producing oscillator's pitch, you create the regular pitch wobble that defines vibrato.

Question 4

In the context of FM (Frequency Modulation) synthesis, what are the respective roles of the 'carrier' and 'modulator' oscillators?

Accepted Answer

The carrier produces the audible tone, and the modulator alters its frequency to create new timbres.

Answer

In a basic FM synthesis patch, the 'carrier' is the oscillator that produces the final, audible sound. The 'modulator' is another oscillator (typically operating at an audio rate) whose output is used to modulate the frequency of the carrier. This modulation creates complex sideband frequencies, resulting in new and often non-harmonic timbres.

Question 5

A producer wants to design a sound that continuously evolves by morphing through a series of different complex harmonic shapes. Which type of synthesis is specifically designed around this concept of scanning through a sequence of single-cycle waveforms?

Accepted Answer

Wavetable Synthesis

Answer

Wavetable synthesis is built on the principle of using a 'wavetable,' which is a collection of different single-cycle waveforms stored in a list. The synthesizer can then scan or 'morph' between these waveforms using a modulation source like an LFO or envelope. This creates dynamic, evolving timbres that are difficult to achieve with other synthesis methods.

Music & Audio Advice Practice Test

Music & Audio Advice Practice Test

Music & Audio Advice Synthesis and Sound Design Questions and Answers 1