1. EE2F2: Music Technology - Revision
Two exam questions
Music Recording Technology
Mixing & multi-track recording
Effects
MIDI & Sequencers
Virtual Studio Technology
Sampling & Synthesis
Sounds & Timbre
Subtractive & Additive Synthesis
Sampling & Digital Synthesis
Physical Modelling

2. Mock Exam Paper Music Recording Technology.
(a) Give two examples of dynamic effects and describe their effect on the sound.
Limiting: Heavily attenuates loud portions of sound, limits the dynamic range to a preset range of amplitudes
Compression: Partially attenuates loud sounds (not as much as a limiter). Compresses the dynamic range
Overdrive: Soft-clipping effect, introduces extra harmonic content
Distortion: Hard-clipping effect, typical rock guitar sound

3. (f) Explain the function of the following MIDI messages and list the information contained in each one:
Note On
Note Off
(iii) Control Change
Transmitted at the instant a key is pressed to indicate the start of a note.
Contains: MIDI channel, note number, velocity
Transmitted at the instant a key is released to indicate the end of a note.
Contains: MIDI channel, note number, release velocity
Used to control parameters such as volume, panning, sustain pedal etc.
Contains: MIDI channel, controller number, new controller value

4. (g) State two advantages of using virtual instruments and effects.
Cost: Much cheaper than real instruments
Size: They are virtual so they don’t take up any physical space
Flexibility: Can be upgraded with software patches as easily as any other program
Ease of Use: Large high resolution computer monitor with GUI controls rather than tiny LCD display
Digital Output: Can be mixed with other virtual instruments using a virtual mixer and effects

5. Sampling & Synthesis
(a) What advantages do modern digital samplers exhibit compared with analogue tape-based samplers like the Mellotron?
High, digital audio fidelity
No moving parts – more reliable
Smaller and cheaper
Random access memory means looping is possible

6. (b) Explain how the length of a sample can be extended using looping.
After the attack portion, many samples don’t evolve that much.
To save memory, this section of the sound can be repeated creating a potentially infinitely long sample.
(c) What steps should be taken to ensure the looped sound is undistorted?
Around the looping point, the sample must be continuous in terms of amplitude and of phase.
Discontinuities in either will result in audible clicks.

7. (d) How can the pitch of a sample be altered?
If the sample is played back at a faster rate, the pitch is higher; at a lower rate, the pitch is lower.
Playback rate should be increased by a factor of 21/12 per semitone.
(e) Explain how multi-sampled instruments work and why they are used.
If the pitch of a sample is changed too much, it starts to sound wrong (‘squeaky’ if too high, ‘hollow’ if too low).
Multi-sampling takes samples at more than one pitch spread across the keyboard. When a key is pressed, the sample closest in pitch is selected and scaled if necessary.

8. (f). Describe how sample & synthesis techniques can
(f) Describe how sample & synthesis techniques can improve a sampled sound.
A sampled sound always comes out the same regardless of key velocity, modulation etc.
Also, only real sounds can be sampled.
Sample & synthesis allows:
Changing the amplitude and timbre of the sample in response to performance input.
Creating entirely new sounds based on real samples.

9. (g). Compare the relative merits of analogue subtractive
(g) Compare the relative merits of analogue subtractive synthesisers, analogue additive synthesisers and digital FM synthesisers.
Subtractive Synthesisers
Relatively easy to program. Synthetic quality. Some timbres are impossible to synthesise
Additive Synthesisers
Difficult to program without computer assistance. Any combination of harmonics is possible. Limited number of oscillators leads to synthetic quality.
Digital FM Synthesisers
Very difficult to program. Highly realistic sounds possible with relatively few parameters.

10. Final Points Keep your answers short – there are no marks for waffle
Look at all the material we covered:
Course notes
Lecture notes
Lab work