It turned out to be not too difficult to find the mathematical explanation of the "vertical yaw" response. In fact it is sitting in plain sight in the standard expressions describing 3-dimensional spatial rotations. Indeed, the response is the sum of two terms, which could be send over separate MIDI channels.

Ian

Hello --

I believe I have resolved my question about the "roll" vs "pendulum swing" responses. Actually they are the same thing, namely a rotation about a fixed (earth-frame) axis. Makes sense once you get it.

Thanks for the great discussion!

Ian

Thank you for your response.

My question was not a technical one at all. It was simply a question to other users as to whether anyone was employing this gestural response I stumbled upon, and if there was any documentation for it.

Knowing very little about IMU operation, I was careful to state that I have no opinion as to separating responses, etc. I do enjoy having CW and CCW rotations split, but that was simple to do in my Reaktor ensemble, and certainly nothing to make a special request about.

Ian

@peter-ostry
Many thanks for your reply. Yes, it is “yaw”. I don’t know any German, so I cannot comment on that particular linguistic appellation.

I appreciate your insight as to Aodyo’s intentions. But my original question remains: where exactly do they explain the yaw feature? Since this motion greatly increases the expressiveness of the instrument, why would they deliberately fail to mention it? Or have I just not looked in the right place? That is my question.

Pedro says that when he pointed out the yaw question to Aodyo (Jonathan, specifically) they had no response except to ask to see a video. He may make a demonstration in addition to mine when he has more time. Pedro was totally surprised when I explained the yaw feature to him. Why would a person who helped in the instrument’s design be unaware of this quite important and useful response?

My own direct inquiry to Aodyo has not received a reply yet.

I have no opinion as to whether the two responses should be combined or not. In my Reaktor program I have followed Pedro’s suggestion to process the R and L “roll” variables separately, as you can see in the two clips. I have been enjoying being able to control various synth parameters this way. But it would be quite an effort to set up and program another pair of these.

One final point: I also have a TEController MIDI device which I use as an accelerometer on my personal, custom wind controller. I was very surprised to see that its outputs seem to be exactly the same as Sylphyo’s! I can switch controllers and see no difference. And this includes the “roll/yaw” combination on a single MIDI CC.

Thanks for the discussion.

Ian

Thank you for the reply.

The usual designation for "roll" is rotation around the long axis of the instrument. If you hold the instrument vertically and apply that same rotation along the long axis of the instrument you get no output signal from the accelerometer. That's how they work. The manual even points out that you have to have some elevation to use "roll".

This "new" gesture is different. It is a rotation around a different axis, namely the radial axis pointing outward from the body of the instrument. You can call it a roll motion if you like but it is not the same gesture as what is usually denoted as "roll". I might suggest something like "twist" for this motion. It produces the strongest output at zero "elevation" and zero output at horizontal orientation, the opposite of "roll".

Pedro has pointed out that this "new" motion is a complementary motion to "roll" and he believes it should be output as a separate MIDI signal, rather than being combined with "roll" in CC76. We have both written to Aodyo; so far they have just asked to see a video, which is what this post links to.

There are many explanations of how accelerometers work online. If you are so inclined you might look one up. My favorite is the Texas Instrument Application Note on the subject.

Ian

Hello --

I am new at using Sylphyo, and am having difficulty understanding part of its behavior. I have not come across any discussion or demos of this behavior, and would be most appreciative if some kind soul would give me a pointer to where I should look.

It's somewhat difficult to describe what gesture I am using, so I made a crude but short video of the gesture and a MIDI monitor display of the signal. It is here on dropbox:

https://www.dropbox.com/s/e7j7u6k7mjzic31/CC76.mp4?dl=0

Many thanks to anyone who would take the trouble to look at this.

Ian

Similar solution here. A square of softish rubber (from a dead exercise ball) rolled into a “C” shape and inserted with the open section facing downward. No pooling and very little wind noise.

@Blonk said in Blocking the Bell Port:

Definitively not at the same complexity level, nor investment, my quick & dirty solution is to use a piece of rubber hose, cut on its length, and rolled on itself, providing a reduction of section.

With changing the hose diameter, when bigger will require more turns, hence reducing even more the remaining air passage.)
The only issue is to not lose it after cleaning !

@join
Well, I’ve tried the new firmware, and indeed it is a huge improvment. Any way I slide my thumb the octaves snap cleanly into place. Great job!

That being said, I still occassionally get the stuck notes in an actual playing situation. This means my thumb must must be coming off the pads. Clearly I need more practice. I’m used to having mechanical switches, which are very forgiving.

Still, I don’t see why your code allows a discrepancy between fingering and note output (except momentarily, of course). My code always checks and waits multiples of the reaction time until there is agreement.

Ian

Jonathan —

Thanks for your input and your time.

I’d just about come to the same conclusion about touch and speed. Additionally, dry, hard skin seems to be a problem. Mr. Steiner says the best solution is to rub in pure glycerin rather than ordinary hand lotion, so I’ll try that, too.

I’ll install the new firmware later today. When developing my own custom controller, I found having a longer dead time when an octave key is involved makes a huge difference in playability.

Of course you may email me!

Ian

@join said in Octave issues:

It could arise if you use a light touch and move slowly on the octave keys, but it depends on the player and some Sylphyo are more forgiving than others. Generally it's recommended to push your thumb a bit more and move a bit faster, which effectively could require a bit of training. With the Sylphyo I have on hand, the issue (spurious note stuck) is apparent with an exaggeratedly slow thumb movement when I set the 5+2 mode, or better, a fingering where the thumb can change the note, like Recorder. Maxence can't reproduce the issue on his Sylphyo. @ijfritz If you don't mind, may I send you an email to discuss your issues in more detail and figure out something to mitigate it?

@jcfitn I followed your method and it works really well for me. A strip of Al foil and a piece of tape ... that's all!

Ian