Musical Timbre Transfer Quiz

Answers and explanations appear as you take the quiz.

1. In timbre transfer, what is preserved from the original audio?
   • The instrument's spectral fingerprint
   • The recording's file format
   • The pitch, loudness, and timing of the performance
   • The background reverb only
2. What does 'timbre' actually refer to?
   • How loud a sound is
   • The tonal color that distinguishes instruments playing the same note
   • The speed of a song
   • The key signature
3. What makes Google's DDSP approach especially data-efficient?
   • It bakes classic differentiable synthesizer structure into the network
   • It uses enormous labeled datasets
   • It ignores pitch entirely
   • It only works on drums
4. Why must the synthesizer in DDSP be 'differentiable'?
   • So it can run on mobile phones
   • So it can play multiple notes
   • So it compresses audio
   • So gradients can flow back through it during training
5. Which two control signals does DDSP typically extract from the input performance?
   • Tempo and key
   • Fundamental frequency and loudness envelope
   • File size and bitrate
   • Lyrics and chords
6. What source type did the original DDSP paper use in the harmonic-plus-noise experiments discussed here?
   • Every possible polyphonic mixture without any representation changes
   • Only silent recordings with no pitched content
   • Monophonic sources modeled around a single fundamental-frequency trajectory
   • Only MIDI event labels with no audio sources
7. In the DDSP approach described here, which synthesis components render the predicted timbre controls into sound?
   • Only a text-to-speech phoneme decoder
   • Only a classifier assigning an instrument name
   • A nearest-neighbor lookup of complete prerecorded performances
   • A harmonic oscillator bank combined with filtered noise
8. What does DDSP's spectral reconstruction objective compare during timbre-transfer training?
   • The generated and target audio's spectrogram representations
   • Only the two recordings' file names
   • Only the number of notes written in sheet music
   • The album covers' color histograms