I've enclosed my solution to the Data-to-Music problem. It uses the top-octave kit, a couple of Data Selectors and an 8-bit Binary Divider. With it, a 7-bit binary number can produce any equally-tempered note in a 7-octave range. By multiplexing the input data at a rate well above audio levels, Polyphony can be simulated. By using the circuit with a PLL circuit, intermediate tones, portamento, and other FM effects can be produced. Unfortunately, I have not found any decent info anywhere on using the CD4046 with the Top-Octave Generator.

But the best part of the circuit is it's simplicity and economy. The remaining data bit (in an 8-bit system) can be used for triggering envelope generators, so a quite advanced polyphonic system can be produced.