Chord-seq to OMChroma

Passing data from Chord-seq to an OMChroma synthesis class (as add-1).

The chord-seq's data must be converted in order to be used with Csound.

The conversions requested are the following:

• midicent to frequency using the mc->f function
• time from milliseconds to seconds dividing by 1000 onsets and durations (or using the ms->sec function)
• velocity to amplitude (for more details see Tutorial 01_08 Velocity versus Amplitude).

In the example A observe in the sound object the amplitude of the chords rendered by add-1.

The first chord has 4 notes and an amplitude of 0 dB.

The second chord has 2 notes and an amplitude of about 1/2 of the first one.

The third chord has only 1 note and an amplitude of about 1/4 of the first one.

Although it is difficult to exactly compute the amount (as it depends on the frequency and phase of each note), the amplitude of 4 simultaneous notes is higher than that of 2 notes, and therefore a sort of amplitude compensation might be needed.

In the example B the list of amplitudes (1 1 1 1 2 2 4) balances the density of the chords.

The example C gives a demonstration of the usage of polyphony without chord's density compensation.