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Synth MIDI Voice
In the Synth dialog, MIDI Voice controls the synthesizer's instrument sound or "patch" that will be used instead of (or in addition to) the Daqarta Generator.
Most modern sound cards no longer have built-in hardware synthesizers, but instead rely on the Microsoft GS Wavetable Software Synthesizer. This provides 128 different tonal General MIDI Instrument Sounds by setting MIDI Voice numbers 0-127. The Synth MIDI Note number is used to control frequency.
The General MIDI name of the current sound selection appears above the control. Although all modern software and hardware synthesizers support the General MIDI set of sounds, some older external or sound card hardware synths, with their own sound sets, may have sounds that bear no relation to these General MIDI names.
Note: If you set MIDI Voice to 128, the name above the control will change to "Percussion". In this mode, MIDI Note number is used to select from the General MIDI Percussion Sounds, which are non-tonal and so don't have a particular "note" or frequency. The name of the selected percussion instrument is then shown above MIDI Note.
Since synthesizer sounds were designed for musical use, none are specifically designated as standard waveforms like Sine, Square, or Triangle. In addition, most have attack and decay dynamics, plus modulation like vibrato (wavering pitch) or tremolo (wavering amplitude) that may make them unsuitable for lab-type uses.
Ocarina sound 79 is a very good sine wave, with minimal attack dynamics and no modulation on the Microsoft GS synth. Because each synthesizer may interpret a sound differently, this same selection may not be the best sine wave on other synths... you may need to scroll through the whole set to find the best choice. Check the "Pipe" sounds 72-79 in particular.
To see the Synth waveforms directly, without having to externally route the Line Out to Line In, you may be able to select Synth from the Line Select section of the Input Control Dialog. If you don't see a line called Synth or MIDI, try "Stereo Mix" or "What You Hear". Note that you may need to unplug headphones (or any cable) from the output jack to get this to work.
Note that in Windows Vista and later systems, you can usually just toggle Input on; whatever sound was going to the output will automatically be routed to the input by default, with no need for Stereo Mix.
As mentioned, most synth sounds have an initial attack portion that dies away to some sustained waveform that is usually softer. You may not notice the transient attack portion during your search, and in fact it may not matter if you intend to use is as a continuous signal. But if you use the Synth Burst option, this could become an issue.
See also Synthesizer Control Dialog.
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