SP-MIDI Dialog Box

In this window, you can create the message used to tell a device with limited polyphony capabilities which channels it should play. To use this dialog box, set values for the fields listed below. Play the music and listen to how it sounds. Then adjust the values and play the piece again, adjusting values as needed to create the best sound. Creating SP-MIDI files is a highly interactive and iterative process. Listening carefully and paying attention to the realtime polyphony levels will result in a great-sounding file, even on a low-polyphony device.

The top of the window lists the following fields: Priority, Channel, File Polyphony, Realtime Polyphony, Peak Polyphony, User Polyphony, MIP, Solo, and Mute.

Priority determines which Channels (displayed in the next column over) play under the most strict conditions. You can change a channel's priority by using the arrow buttons at the bottom of the list.

File Polyphony shows the maximum number of simultaneous MIDI notes present on that channel. Play your file using the transport controls at the bottom of the window. Playing the file fills in the values for Realtime Polyphony and Peak Polyphony.

Realtime Polyphony shows the actual number of overlapping voices present on the channel, taking into account the decay segment of the sound. This is how your device perceives polyphony.

Peak Polyphony indicates the maximum Realtime Polyphony value for that channel.

User Polyphony is where you assign a polyphony level to a channel. For example, you may have a channel with a Peak Polyphony of 8, but it only peaks at 8 when no other channels are playing. Depending on the priority you assign it, if you give it a User Polyphony of 8, you may never actually hear that channel because it takes up too many voices.

MIP, or Maximum Instantaneous Polyphony, is a value based on the Priority and User Polyphony values you've set for your file. It adds the number of voices needed to play it and all channels of higher priority.

Solo is used to play a single channel.

Mute is used to mute a channel.