Note on/off without pitch detection

The G2M™ Universal Guitar to MIDI Converter.

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JamieS
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Joined: Mon May 04, 2015 5:57 pm

Note on/off without pitch detection

Post by JamieS »

I'm interested in picking up a G2M for use with synths. However, I generally use the synths to process audio rather than generate it, so my main concern is triggering envelopes and syncing LFOs and whatnot via MIDI notes. I think the G2M should work fine for this purpose with monophonic signals. However, if I play a chord on the guitar, I'd like to generate a Note On message, and I don't particularly care if the pitch tracks. Will the G2M actually generate a Note On/Off message for polyphonic signals, or will it just get confused and send nothing? Or worse, send a whole bunch of stuff as it tries to figure out what note is being played? Is it possible to configure it such that it can generate Note On/Off for polyphonic signals?

Thanks!
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james
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Joined: Fri Jun 06, 2008 8:12 pm

Re: Note on/off without pitch detection

Post by james »

With a polyphonic signal, such as a chord, the G2M will try to track a single note. Typically the first note, or strongest note if notes are played simultaneously. But it really depends on which notes are played together.

The problem is the G2M is fast. Very fast. So it doesn't have any time to wait to analyse the sound to work out what has been played. Instead it has to always make a best guess, assuming the input is mainly monophonic.

If you think about two notes playing together. If these are close together they can beat, this beating can sound a lot like two notes being played quickly. The G2M can't tell the difference between you playing two notes alternately, or sustaining two notes that are beating together. So it assumes you are playing two notes and you may get a stream of notes.

It depends how close the notes are together. Low notes are closer in frequency so these cause more problems. For example, on a bass guitar the problem is worse than on guitar because the very low bass notes are so close in frequency.

With a multi-note chord, it just depends which notes are played and how close together these are in frequency.

Even with all these potential problems, playing 2 or 3 note chords is usually not a problem and the G2M will track the root note of the chord most of the time.
JamieS
Posts: 3
Joined: Mon May 04, 2015 5:57 pm

Re: Note on/off without pitch detection

Post by JamieS »

Thanks! Makes perfect sense. That might work fine as is. I don't suppose there's any way to configure it to output a single note that's always the same, and just track the signal envelope for note on and off?

-Jamie
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james
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Re: Note on/off without pitch detection

Post by james »

The G2M doesn't have any configuration options.

The i2M musicport (http://www.sonuus.com/products_i2m_mp.html) does have ways to configure this. But it's USB-MIDI, not 5-pin MIDI. You'd need some way to interface that to the rest of your setup.
JamieS
Posts: 3
Joined: Mon May 04, 2015 5:57 pm

Re: Note on/off without pitch detection

Post by JamieS »

Thanks!
addseo1115
Posts: 4
Joined: Fri May 15, 2015 5:27 am

Re: Note on/off without pitch detection

Post by addseo1115 »

Thanks!
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