Unfortunately there is nothing anyone can do to help.

If you are 'quite sure something is broken' you should contact your nearest service center and have them take a look at it.

More likely, though, is your experience is just the way the Touch settings work. You will just have to find which of the 5 touch settings work best for you and use that setting.

While that instrument model will accept MIDI NOTE ON events with the full velocity range it doesn't have functionality that allows you to specify a velocity curve/setting other than the velocity to use if you also select FIXED for the curve.

I pre-ordered the YC61 and sold it and bought the YC73 which is a fantastic looking & sounding board.

I think the YC61 might be better however the YC73 is pretty bad also. A design flaw perhaps or was copied from the CP series and never really fixed which should never happen.

My issue became clear when I ordered the CK and noticed something very different not that the CK is any better but it was tweaked to respond louder I think. Meaning level of 64 on the CK activates more samples than does the YC at the same level. I had to turn the YC up to 128 to get the triggering to happen. The curves really do nothing much.

Next I was blown away by the responsiveness of the EE Osmose almost barely touching the keys it would trigger and then it responds like it has endless sensors. So I MIDI'd it to my YC and it was like I had a brand new YC stage board. Why Yamaha doesn't test products before releasing them for production I have no idea but I suspect they know and just don't care. Hoping nobody would notice but touch and expression is second only to quality of sound. It's the only means we have of making our music speak. IF that doesn't work, like all I had was soft and hard and nothing else, the nit becomes boring instantly.

Go listen to Blake play the YC "Global Stage" link on the top right and watch how hard/soft he is hitting the keys and nothing is happening. Same thing it's either loud or soft or nothing. The way it should be is whisper quiet, soft, medium-soft, medium, medium-hard, hard and thunderous. I can get this no problem on the Osmose. It also sounds like waveform samples aren't triggering unless you turn the velocity way up and then all it does is play too hard all the time.

They need to go back to the drawing board and seriously design that system. Other manufacture's might be the same way too just because the keys are the aftertought to the whole concept. Osmose has made everyone look bad because without expressiveness you have nothing more than a percussive chromatic xylophone.

david - I think it is a software-issue. Do you agree?

Unfortunately I think it's a mechanical or hardware problem else they would have already fixed it. Maybe it can be improved but physical triggering and physical sensors are likely the issue because Osmose plays it correctly. Good news is you can pair it with an Osmose if you want a better experience. There might be other type portable controllers that work correctly and with more keys. No way to know until you test it out. IF there are essentially unlimited levels of key strike velocity how would only a two sensor system even work? It's what we've all been sold for 30 years so only now is something like "endless sensors" or what's called key pressure has exposed the shortcoming of traditional designs. We have on/off/sustain and that's it.

With AMW2 sampling what doesn't happen is that every note of an instrument isn't sampled at 10 different strikes or velocities or timbres but that's how a real instrument sounds. The data to assemble that waveform would be impossible to process and then your hardware would have to sense 10 different velocities to play all those unique variations. This is why modeling is the best way to replicate real instruments, it's more expressive and unlimited in what it can achieve including 10 different timbre variations.

However a piano or EP shouldn't be as complex as a trumpet or sax but it does have variations at least in key strikes and volume and reflections. That's what some are talking about whether Montage M with employ Yamaha's patent on string resonance and other realistic simulations that sampling can't do in a practical way. More technically minded engineers and designers can explain it better but the keys are the windows into the soul of the music. Banging out notes on a xylophone isn't good enough for musical expression anymore.

My YC73 keys drop down about 3/8" and then hits rock bottom. All it does is "On" or "Off". It should do 10% on, 20% on, 30% on, 40% on, 50% on, 60% on, 70% on, 80% on, 90% on, 100% on as an example and each of those should sound different. It tries to detect velocity and then play either louder or trigger a different sample but no matter how hard you slam it down nothing changes. Whatever technically is happening it doesn't work correctly. It's several things that are happening in software and hardware combined. IF the sensor mechanism isn't good enough software won't matter. At least it sounds better on a different controller so all hope is not lost.

My philosophy now in light of better technology is that if keys are going to be included on boards, they need to be completely redesigned to handle everything in every situation. They need to be expressive because the greatest software or samples in the universe don't mean anything if you press a key 10 different ways and all you get is "On" or "Off".

I think it is a software-issue.

If it is then your only hope for a solution is to make sure you are using the LATEST version of the OS which you can get here
https://usa.yamaha.com/products/music_production/stagekeyboards/yc/downloads.html

Try that and see if it helps. I hope it does.

But if it was a software issue then EVERY model YC61 they ever sold would have the same issue.

They do all have the same issue it's just that no one notices because all boards perform rather poorly in general. Keys are the afterthought to every keyboard. The Blake video shows it doesn't work correctly in real time and he has three sensors on the 88. All I see him doing in dynamics is soft or hard nothing else not because of him.

I'm sure Montage doesn't work correctly either but I don't have one here to compare. Let's assume 95% of all keyboards everywhere don't work correctly. Does that mean they all do work correctly because that's the norm? Which is some barely acceptable On/Off mechanism. Or like now when a keyboard that shows how everything should work is released, in comparison all those 95% don't work correctly.

I guess "correctly" is subjective (there also also can be limitations considered as defective within any classification) but once you play a "correct" keyboard everything else is awful. Depends on your goal too. IF your goal is to play magnificent chords all over the scales with fast runs and rhythm then you don't really care about expression because the wow factor is the difficulty of the performance, timing etc.

IF you want to express yourself from near silence to thunder and make a note sad, happy, angry or playful then realism is all that matters and interaction with the keys. Like Jazz for exmaple. A stage board could indeed fail at expression and be considered acceptable if it's goal is to only be a xylophone. A synth should be about nothing but expression. I think all boards should focus on expression no matter what classification they are.

A piano player probably doesn't care because a real piano can only play like a piano and nothing else. It's soft, medium or hard and that's all except for the pedal enhancements. I assume keyboard manufacturer's are only after piano action and that's all even on a synth which is unacceptable. A synth should be expressive in the ultimate sense and I don't just mean adding aftertouch and some wheels. Poly touch isn't even the norm which the CS80 had in the 70s.

It's a product budget issue I guess that's been around too long with way too many bad action keyboards. It's been the norm for so long nobody has demanded better. As soon as someone builds a flagship workstation and makes the transition to Osmose level key expression then everyone will be forced to follow. We'll all wonder why has it taken this long? It's astonishing to me 50 years after CS80 we still use on/off triggers and occasionally monotouch.

Someone said the YC73 was a copy of the CP line or model but if it were only a software issue they did update the OS to add customized velocity curves, I think it already had the touch response options but I attempted to simulate the Osmose action as the controller and nothing worked. The CK was different from YC as it was juiced up or hot in comparison. Cranking it up to be more forward doesn't mean it's more expressive. I recreated something similar by tuning the 64 up to 128 on the YC. That's like turning up the volume thinking it's going to make it more expressive. That's not the same thing as dynamics.