Vidal - new midi controller being developed

And I hope that thought this through correctly, because if our pivot length is REALLY long, you also need to increase a lot the spacing between the lines of the membrane switches (either 2 or 3 contacts... does not matter) to compensate for the smaller "rotational" effect of the key. If you use PCBs with a similar spacing as in regular DPs, both pads will be activated in very quick succession, which is not a problem by itself, but means that there is absolutely no room for any manufacturing irregularity. Any small tilt in the PCB or any difference in the distance of each wooden key to the PCB (hello humidity!!!) will make the midi reading jump as crazy.

and unless I'm mistaken, membrane switches are really crappy for sensing velocity. That's what they use in cheap TV remote controls. I'm no expert at DP actions - do any good ones use membrane switches?

So should I order a piano that's not yet in production? And that's been tried and evaluated by no one?

Kinda reminds me of Pelosi-era House bills. "You've gotta pass the bill before you get to read it."

Nope. Not for me.

It seems “Vidal” has been around for quite some time, yet only recently did they venture into the ‘digital piano’ business.

I must say, if their pianos turn out to be anything like their hair products, I’m all in:

https://youtu.be/Tmt3Q9qclTE

I tease, yet do I?😆

dore_m and unless I'm mistaken, membrane switches are really crappy for sensing velocity. That's what they use in cheap TV remote controls. I'm no expert at DP actions - do any good ones use membrane switches?

They don't use them to sense velocity from a single such sensor. They are used as binary switches instead, placed in a specific way, so that they are mechanically pressed in succession (e.g. they are pressed by notches of different length), so that time is measured between the two activations, hence velocity can be devised. That's why there are "two-sensor" and "triple-sensor" actions.

vagfilm And I hope that thought this through correctly, because if our pivot length is REALLY long, you also need to increase a lot the spacing between the lines of the membrane switches (either 2 or 3 contacts... does not matter) to compensate for the smaller "rotational" effect of the key.

From the photo, the fulcrum seems to be at the far rear side and the sensors (the little green part of PCB we see) half way. Then there are still some movement to measure (half the shift of the front of the key). Note, sensors don't measure a "rotational" effect. Only a movement of the part of the key on the top of it.

Frédéric L Note, sensors don't measure a "rotational" effect.

I know that... You did not follow my argument (maybe because I did not explain myself well...). As CG mentioned above, these membrane switches don't measure absolute time but difference between successive activation of two switches: when the key is pressed, it first activates the back switch and then the front one (and also mid sensor, in 3 sensor actions), and these are usually only a few mms apart. If the pivot is short, the key bottoms at a steep angle (what I called rotational effect); if the pivot is long, the angle is shallow. In a theoretical infinite pivot (same displacement at the back and front of the key) you simply cannot use successive sensor strategy because the sensors are all activated simultaneously. Thus, membrane switches are a bad strategy if you have optimal pivot length, unless you place one switch close to the fulcrum and the other close to the key front.

vagfilm In a theoretical infinite pivot (same displacement at the back and front of the key) you simply cannot use successive sensor strategy because the sensors are activated simultaneously.

What you need is to have sensor close enough to the front of the key, or if you prefer far from the fulcrum.

Then here with sensors half way between the front and the fulcrum, the movement seen by sensors are half the movement of the key front. I can be enough whatever the key length.

With an infinite length key, the sensor can't be closed to the fulcrum, and is relatively very near the key front. Then When the front is depressed by 5mm, the sensor will see 5mm of movement. It can't be better.

Note the sensors will be mounted at different height, then they are activated successively.

Again, missing the main point of my criticism which does not have to do with electronics (sensors are fast enough to measure successive pressing even if put in the worst location) but with manufacturing tolerance. Using this design is not a problem for sensing a single key. It is a problem (or may be more problemtic, to be correct) for calibration across keys. Sensors in close proximity require strict manufacturing and assembly because there is less tolerence. If the pcb under one octave is tightened with one more turn of the screw and the pcb rests a quarter of mm further from the key than in other octaves (it takes usually several pcbs to cover the 88 keys) that causes a large difference in velocity reading. On the other hand, if the sensors are very far from each other, there is more room for assemblage differences. Better tolerance, easier calibration.

what's providing the counter force ?

is it spring loaded, or are those round things underneath next to their dome board magnets ?

The issue is not the distance between sensor in the horizontal dimension, but the relative height. We can also have an horizontal set of sensors but the key trigger them with "fingers" of different length.

What you need from a calibration perspective is that the height of the sensor don't impact too much the measured velocity. Here, the best thing is to put the sensor under the front key. Then 5mm of offset is equal to 5mm at the sensor. And a 0.05mm of mechanical tolerance is only 1%. of the whole movement of the key. If you put the sensors half way between fulcrum and key front, the same key action will trigger a 2.5mm movement at the sensor position, and the same tolerance (0.05mm) would be 2% relatively, then the velocity measure error will double. This maths are the same with long keys and short keys. Only the relative position of the sensors on the fulcrum key front axis is important.

in terms of tolerance, wood is the problem here, they should've went with a plastic spine keysticks and steel laser cut mounting rail.

I have said the relative position on the fulcrum-front axis. The different of height (or finger length) is important too.

But if we put a too much finger length difference, the repetition speed will be lesser (we had to release more the key). See https://www.youtube.com/watch?v=AnqHStIL02E

Frédéric L but the relative height

Yes, of course, since a straight object that does not bend, will only touch another surface at multiple points if both planes are parallel. That is the reason why keyboards have rubber domes above the sensors and the rubber is thicker (or higher) on the first sensor. Without that artificial "distortion" of the plane of the key, the key could only have one moment of activation of the pcb (either the key touches all pcb points at the same time, or touches the first point and it stops there never reaching the second; or maybe I am embarassing myself by failing in basic geometry reasoning... Not my first time).
We are basically in agreement and talking in circles. Let the vidal engineering team figure the calibration out (maybe they can compensate by having larger differences in the rubber domes...).

SouthPark I guess they will put the strip on the 88 keys . Good spot SouthPark

kawafanboi what's providing the counter force ?

is it spring loaded, or are those round things underneath next to their dome board magnets ?

Why the cynicism?

They’ve stated -very clearly- how great the action, yet you’re bent on an inquisition!

What if they’ve figured out a way to defy the laws of gravity? surely, we have no idea what kind of alien-tech the guys at Vidal Sassoon have at their disposal.

Shame on you all, for such cynicism!

Independently of what the end product is going to be like , the feature I like is the ability to access the action straight away as a feature . How many times do we see on forums , ´ I got a sticky key ‘ and as a response get ‘ consult a certified dealer to carry out the operation ) which is frankly disappointing. It seems like the brands want to make collateral business by making maintenance difficult for end users, not publishing service manuals etc… this doesn’t really exist in the acoustic world. Of course you need to know your stuff if you want to regulate or tune your piano , but it is accessible . In the DP world , it seems that end users are discouraged to open their instruments , even though many things can happen to the action and the keys because even if the sound is produced electronically , DP’s are still percussive from a key standpoint and will be subject to various issues at some stage . Is the philosophy ‘ bin it and buy another one ‘ the rule here similarly to swatch watches ? Sorry end of the week , rant time 😉

Pete14 haha …… true. It's possible that they used a-tech (alien tech) … worm-hole drive technology. It can really open up a can of worm-holes.

Jokes aside. Hopefully Vidal can send a 'sample' midi controller to us at PC for review and to keep. We will draw straws on who keeps it. Would be good publicity. And if they pay us enough, we'll have all good things to say about it!

Love that extra special touch on their midi controller finishing as well. Aka box joint.

CyberGene they’re just ignorant

There is definitely something in this. Even the location/placement of the pitch shift stick. I wouldn't put it there just 'above' the dial thing. I need to have a chat with whoever it was that decided to just plonk it there - without some practical thinking.

I would keep the pitch stick away from the power switch etc too.