High-Pitched Gltich Issues

The i2M musicport™ MIDI Converter & Hi-Z USB Audio Interface

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BeePee
Posts: 5
Joined: Wed Feb 19, 2020 12:32 pm

High-Pitched Gltich Issues

Post by BeePee »

I'm exploring Pitch-to-MIDI solutions for harmonica handheld mics into the iPad. I've been getting pretty good results with the Midi Guitar 2 app, but decided I'd try the Sonuus i2M and see how it compared.

I found the speed and overall accuracy of tracking very impressive! BUT the deal breaker right now is that the MIDI signal randomly leaps to very high-pitched notes that seem to be a couple of octaves up from the pitch of the notes I'm playing. Currently this makes the i2M unusable for me and I'll need to return it - unless someone here knows what's happening and can suggest a fix?

My suspicion is that the USB signal combined with my mic input is is too hot. However when I dialed down the volume of the mic the problem kept happening. To check the signal I opened the Sonuus as my interface in Midi Guitar, and found the input signal was way higher than if I go in to Midi Guitar 2 via the Apple CCK with my regular USB interface (a Korg Pandora PX5D multi FX unit). I've tried other guitar USB interfaces and they also give a regular signal with my harmonica mic that can be dialled into the sweet spot for best MG2 signal processing and MIDI tracking.

However, when I tried a straight handheld USB microphone I found the signal was the same as the Sonuus i2M: very hot, and I got the same high-pitched glitch anomalies happening. As far as I can see there is no ability to dial down the level of the USB signal from these sources in Midi Guitar 2, or the synth apps I also tried them through (eg. Poison). I looked into whether one could buy a signal attenuator for USB devices, but couldn't find one. Maybe they don't exist?

I could be barking up the wrong tree thinking it's a USB signal level issue. Does anyone know how I can fix this high-pitch glitch issue? If it's possible, I think the i2M will work great as a pitch-to MIDI solution for harmonica players.
BeePee
Posts: 5
Joined: Wed Feb 19, 2020 12:32 pm

Re: High-Pitched Gltich Issues

Post by BeePee »

Please can someone from Sonuus reply to this ASAP.
BeePee
Posts: 5
Joined: Wed Feb 19, 2020 12:32 pm

Re: High-Pitched Gltich Issues

Post by BeePee »

I did some more tests, trying various kinds of microphone. I'm getting better results with low impedance mics than high impedance, which appear to overdrive the signal. Reducing the harmonic content of the signal by processing it before input to the i2M, as suggested in another thread, is something I'll try also.

It feels very close to being really usable with a microphone, just got to find the optimal input options for non-guitar signals.

It would be great if Sonuus did some research on this area yourselves, so you can advise singers and instrumentalists who want to convert mic audio to midi. After all, that's a huge potential new market for you!

James - can you come back on this?
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