Listening Quiz
Blind A/B exercises that test the ability to identify the effects, filters, and quantization processes taught throughout Sonic. No grade is recorded — the goal is honest practice.
How it works
Each question plays two short clips. Listen to both, then guess which clip is the modified one (or which modification was applied). Reveal the answer to check; click or tap Next to draw a fresh pair from a different source. The clips are generated live in the browser by the same audio engine that powers the interactive demos in each chapter, so what plays here is identical to what the sliders can build.
Which note is sounding? — easy
A single piano-ish tone plays. Pick which diatonic pitch was heard. (Notes are drawn from the C-major scale around middle C.) Without absolute pitch, use Reference C4 as an anchor, and tap any letter to audition that pitch before committing.
Which modulator waveform? — easy
A 440 Hz carrier is frequency-modulated by a fast (12–18 Hz) modulator. At this rate the wobble shape is felt as timbre, not seen as a visible cycle. Sine = smooth, triangle = peaky-but-smooth, square = two-tone clang, sawtooth = ramped buzz.
Spot the compressor
One of the two clips has aggressive compression applied (threshold −30 dB, ratio 10:1, fast attack). Which one?
Name the filter
One clip has been processed by a filter (low-pass, high-pass, band-pass, or notch). Listen, then pick.
Which is lower bit depth?
One clip is 16-bit (CD quality); the other has been quantized to 6 bits or fewer. Listen for the “hash” of quantization noise.
Drag the EQ to match the target — medium
Play the target clip, then drag eight band sliders to reproduce the EQ curve just heard. A/B against the target with the “My EQ” button. Targets are randomised within a ±6 dB range and within ±6 dB RMS error scores a pass — precise matching isn’t expected, the goal is to feel out the overall shape (bright vs. dark, scooped vs. honky).
Which ADSR envelope matches? — medium
A gated 220 Hz sawtooth tone is shaped by one of four classic ADSR envelopes (Pluck, Pad, Organ, Bowed). Listen, then pick the curve that produced it.
Above or below the 40-phon contour? — medium
The reference button plays a 1 kHz tone at 40 phon (40 dB SPL by definition). The test button plays a different frequency at a different SPL. Decide whether the test tone sounds louder or quieter than the reference. (Note: the absolute SPL depends on playback volume — this is a relative judgement of equal loudness.)
Score this session
Correct: 0 · Attempts: 0
Tip: chance accuracy is 50 % on yes/no questions, 25 % on four-way questions (filter, modulator, ADSR), and roughly 14 % on the seven-way pitch question. Beating 80 % consistently is a mark of a trained ear.