How did encoded-score instruments control pitch, loudness, tone colour, and note articulation?

Encoded-score instruments were designed to automate musical performance by reading instructions from physical media, such as paper rolls or cardboard cards, to control electronic circuits that generated sound.123

• Pitch and Tone Colour: These instruments used encoded data to specify the frequency and harmonic content of the sound. For example, the RCA Electronic Music Synthesizer utilized binary information perforated onto paper rolls to define the pitch and tone colour for multiple simultaneous tones.2
• Loudness and Articulation: The encoded score provided precise instructions for the intensity (loudness) and the shaping of the sound, including envelope characteristics and portamento. In the Coupleux-Givelet synthesizer, the paper roll acted as a mechanism to "play" electronic circuits, allowing for the automated control of these musical properties.21
• Precision: By specifying sound properties at frequent intervals—such as every 1/30th of a second in the RCA system—these instruments allowed composers to achieve a level of speed and precision in note articulation that exceeded the capabilities of human performers.2