Study level
A Level
The first half of every lecture is taught at A Level. Here is everything at this level, by lecture and by school year.
Study levelLectures at this level
Lecture 1
Sound, signals and sampling
- Read amplitude, period and frequency from a waveform and use .
- Explain sampling, and use and .
- State and apply the sampling theorem, , and the Nyquist frequency .
- Explain aliasing, and why the anti-aliasing low-pass filter comes first in a PCM transmitter.
Notes: What a signal is · The range of hearing · Why go digital? · Sampling · The sampling theorem · Why a CD samples at 44.1 kHz · Aliasing · The anti-aliasing filter · The PCM transmitter
7 worked examples from the video (L1-Q1, L1-Q2, L1-Q3, L1-Q4, L1-Q7, L1-Q8, L1-Q9) · 7 practice questions
By school year
A Levels in England are linear: everything is examined at the end of Year 13, and schools choose their own order. The boards do mark some content as AS, which is usually taught in Year 12; the rest is usually taught in Year 13. Some boards do not say.
Year 12: AS content
| Qualification | Spec point | Taught in | Coverage |
|---|---|---|---|
| AQA A-level Computer Science | 3.5.6.5 (AS) and 4.5.6.7 digital representation of sound: sample resolution, sampling rate, the Nyquist theorem; sample size in bytes | Lecture 1 | partly covered |
| OCR A Level Physics B (Advancing Physics) | 3.1.1 (a)(iii) digitising a signal, which may contain noise; the advantages and disadvantages of digital signals | Lecture 1 | partly covered |
| OCR A Level Physics B (Advancing Physics) | 3.1.1 (c)(vii) a minimum sampling rate of more than twice the highest frequency | Lecture 1 | covered |
| OCR A Level Physics B (Advancing Physics) | 3.1.1 (c)(vi), (ix), (x) b bits give 2^b levels; digitising at a given number of levels; bits needed for a given signal-to-noise ratio | Lecture 2 (coming) | covered |
| AQA A-level Computer Science | 3.5.6.5 (AS) and 4.5.6.7 sample resolution; sample size in bytes | Lecture 2 (coming) | covered |
| Eduqas A Level Electronics | Core concepts, topic 4 (b); Component 1, topic 5 (b) rms values and AC power; rms and peak | Lecture 3 (coming) | covered |
| AQA A-level Computer Science | 3.5.6.3 (AS) and 4.5.6.3 the principles of an ADC and a DAC | Lecture 4 (coming) | covered |
| Eduqas A Level Electronics | Component 1, topic 5 (c)-(e); topic 3 (k) reactance and impedance; RC low-pass and high-pass filters on linear-log and log-log graphs; bandwidth at 1/√2 of the maximum gain | Lecture 5 (coming) | covered |
Year 13: A level only
| Qualification | Spec point | Taught in | Coverage |
|---|---|---|---|
| Eduqas A Level Electronics | Component 2, topic 4 (c) the PCM link as a block diagram: the transmitter (low-pass filter, sampling gate and clock, ADC, PISO register) and the receiver (Schmitt trigger, SIPO register, DAC, low-pass filter) | Lecture 1 | partly covered |
| Eduqas A Level Electronics | Component 2, topic 4 (d) the sampling frequency needed for a given highest signal frequency; the Nyquist theorem | Lecture 1 | covered |
| Eduqas A Level Electronics | Component 1, topic 4 (e) digitising audio; the effect of sampling rate and resolution | Lecture 1 | partly covered |
| AQA A-level Physics | 3.13.2.1 (Electronics option) sampling audio for digital transmission: sampling rate, quantisation, the pros and cons of digital sampling, recovering data from noise, PCM | Lecture 1 | partly covered |
| Eduqas A Level Electronics | Component 1, topic 4 (f), (g); Appendix A factors affecting flash-ADC resolution; resolution = input voltage range / 2^n | Lecture 2 (coming) | covered |
| AQA A-level Physics | 3.13.2.1 (Electronics option) quantisation; the effect of bits per sample on quality | Lecture 2 (coming) | covered |
| Eduqas A Level Electronics | Component 1, topic 6 (f), (h), (i), (j) decibel power gain and attenuation; total gain of a chain; signal-to-noise ratio in decibels | Lecture 3 (coming) | covered |
| AQA A-level Physics | 3.10.2.2 (Medical physics option) equal-loudness curves; intensity level in decibels; dB and dBA | Lecture 3 (coming) | covered |
| AQA A-level Physics | 3.7.5.5 rms, peak and peak-to-peak values of sinusoids | Lecture 3 (coming) | covered |
| Eduqas A Level Electronics | Component 1, topic 4 (a)-(d), (f), (h) the summing amplifier as a DAC; comparators and the flash ADC; digital ramp against flash | Lecture 4 (coming) | covered |
| Eduqas A Level Electronics | Component 2, topic 4 (c), (e), (f) PCM transmitter and receiver; time-division multiplexing | Lecture 4 (coming) | covered |
| AQA A-level Physics | 3.13.2.1, 3.13.4.3, 3.13.6.3 (Electronics option) ADC and PCM; the summing amplifier; time-division multiplexing | Lecture 4 (coming) | partly covered |
| Eduqas A Level Electronics | Component 2, topic 8 (a), (d); Component 1, topic 5 (e), (f) first-order active tone controls; passive LC band-pass filters, resonant frequency and Q | Lecture 6 (coming) | covered |
| AQA A-level Physics | 3.13.3.1 (Electronics option) LC resonance filters, resonant frequency and Q | Lecture 6 (coming) | covered |
| Eduqas A Level Electronics | Component 2, topic 8 (a)-(c), (e)-(i) audio system structure; preamplifier and mixer; push-pull output stage and maximum power; crossover distortion and negative feedback | Lecture 9 (coming) | covered |
| AQA A-level Physics | 3.13.4.1-3.13.4.4 (Electronics option) op-amp amplifier configurations and the limits of real op-amps | Lecture 9 (coming) | partly covered |
Year not stated by the board
| Qualification | Spec point | Taught in | Coverage |
|---|---|---|---|
| Pearson Edexcel A level Music Technology | Component 4, AoS 2, 2.4 specifications of digital recordings: A/D and D/A conversion, sample rate, bit depth, uncompressed PCM | Lecture 1 | partly covered |
| Pearson Edexcel A level Music Technology | Component 3, AoS 3, 3.1 (bullet: sampling theory and converters) digital hardware: sampling theory and converters | Lecture 1 | covered |
| Pearson Edexcel A level Music Technology | Component 4, AoS 2, 2.5 (bullet: calculations describing sound waves) calculations describing sound waves: frequency, phase, amplitude | Lecture 1 | partly covered |
| Pearson Edexcel A level Music Technology | Component 4, AoS 2, 2.4 bit depth; signal-to-noise ratio and dynamic range; headroom; digital clipping | Lecture 2 (coming) | covered |
| Pearson Edexcel A level Music Technology | Component 4, AoS 2, 2.6 and 2.5; Component 3, AoS 2, 2.3 and 2.4 decibel scales, peak and RMS metering, perceived loudness, levels in decibels | Lecture 3 (coming) | covered |
| Eduqas A Level Physics | Option A (j), (l), (m) capacitor reactance and phase; phasors and the impedance of RC circuits | Lecture 5 (coming) | partly covered |
| Qualifications Scotland (formerly SQA) Advanced Higher Physics | Electromagnetism: Circuits capacitive reactance; the RC time constant | Lecture 5 (coming) | partly covered |
| Pearson Edexcel A level Music Technology | Component 4, AoS 1, 1.11 low-pass and high-pass filters, cut-off frequency and slope, drawn as EQ graphs | Lecture 5 (coming) | partly covered |
| Eduqas A Level Physics | Option A (n), (o), (p) RCL series resonance; the Q factor and sharpness of resonance | Lecture 6 (coming) | covered |
| Pearson Edexcel A level Music Technology | Component 4, AoS 1, 1.11; Component 3, AoS 1, 1.10 shelf, band and pass EQ; parametric and graphic EQ; gain, cut-off, Q, slope, resonance | Lecture 6 (coming) | covered |
| Pearson Edexcel A level Music Technology | Component 3, AoS 1, 1.2; Component 4, 1.3 synthesis from basic waveforms; how timbre changes with filter settings and envelope | Lecture 7 (coming) | partly covered |
| Pearson Edexcel A level Music Technology | Component 3, AoS 3, 3.2 valves and soft clipping; transistor amplifiers and hard clipping | Lecture 9 (coming) | partly covered |
| Pearson Edexcel A level Music Technology | Component 4, AoS 1, 1.12 modulated delay and comb filtering | Lecture 10 (coming) | partly covered |
| Pearson Edexcel A level Music Technology | Component 3, AoS 1, 1.8 and 1.11; Component 4, 1.9 and 1.12 reverb, delay, flanger, chorus and phaser; compression, limiting and gating | Lecture 11 (coming) | covered |
| Pearson Edexcel A level Music Technology | Component 3, AoS 3, 3.1 convolution reverb, named | Lecture 12 (coming) | partly covered |