Miles Sound System SDK 7.2a

MIDIECHO for MacOS - MIDI Data Receiver and Interpreter

Discussion

The MIDIECHO for Mac program receives incoming MIDI Channel Voice and System Exclusive messages via a QuickTime MIDI input, and sends them to a specified Miles Sound System Extended MIDI (XMIDI) driver.

Note: To use a MIDI keyboard, you have to install the Opcode OMS library by Opcode Systems, Inc.

MIDIECHO can be useful for musicians who wish to develop music and sound-effects arrangements for MSS applications. Composers can receive immediate feedback when playing compositions on a MIDI sequencer platform, simply by connecting the host’s MIDI interface to a reasonable-quality MIDI interface on a "slave" Mac system running MIDIECHO.

When starting MIDIECHO, you must choose the capture and playback options.

With the drop-down menus, "MIDI Input Device" and "MIDI Output Device", you can choose the drivers for MIDI input and MIDI output.

The "DLS Bank File" button allows selecting a DLS file for playing music. If you selected QuickTime as MIDI Output Device, you can skip selection of the DLS Bank File.

The "WVL File" button allows selecting a Wave Library file for playing music. If you selected QuickTime as MIDI Output Device, you can skip selection of the Wave Library File.

Once you've made all of your choices, click the OK button, and the main MIDIECHO window will appear.

When MIDIECHO is running, the voice limit slider may be used to adjust the "voice alert limit", or the number of notes which MSS assumes the synthesizer in use can play simultaneously. During a MIDI performance, MIDIECHO presents a continuously updated graphical display of polyphonic note activity.

When the voice alert limit is exceeded, the progress bar begins iterating, and the Total Overflow indicator below the graph will be incremented. This feature may be helpful when diagnosing note "dropout" problems that occur due to partial overflow.

When running on a slower Mac with dense MIDI traffic, MIDIECHO may exhibit undesirable tempo variations due to program overhead. If this problem occurs, the MIDI Trace checkbox can be used to disable the continuously scrolling MIDI event trace, which appears in MIDIECHO’s uppermost window.

The "All Notes Off" button can be pressed at any time to "kill" any stuck notes, which may occur while running MIDIECHO.

During playback, if a combination of XMIDI Patch Bank Select controller and MIDI Program Change number values is used to set up a timbre which cannot be found in the specified Global Timbre Library file, MIDIECHO will complain with an error message.

The "Error Beep" checkbox can be used to enable or disable the Alert Sound when note overflow occurs, or when instrument-loading errors are reported.

The "Filtering" checkbox can be marked to toggle the software synthesizer's filtering mode.

The "Reverberation" checkbox can be marked to toggle the software synthesizer's reverb mode.

MIDIECHO re-transmits incoming data on all 16 MIDI channels to the MSS driver via the AIL_send_channel_voice_message call. The program retransmits all MIDI Channel Voice messages (MIDI System Exclusive messages are retransmitted as well, but this feature should be used with caution since "timing slips" inherent in System Exclusive transmission can cause strange, misleading effects in the music.)

MIDIECHO is intended to receive normal MIDI Channel Voice data, not synthesizer-ready XMIDI data. Timing problems may occur if a dense XMIDI data stream is fed to the MIDIECHO host’s input port.

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Group: Miles Sound System Tools Reference
Related Sections: MIDIECHO for DOS - MIDI Data Receiver and Interpreter, MIDIECHO for Windows - MIDI Data Receiver and Interpreter
Related Functions: AIL_send_channel_voice_message