Just purchased a MODX8, and wondering whether the CF and Bösendorfer piano sounds are programmed in a way that, a continuous SUSTAIN controller like Yamaha FC3A can be used in order to have progressive sustain / half dampening (instead of an on-off switch operation), or not.

Yes, they both are, as are most all the Acoustic Pianos... and those that are not are user programmable...

My experience with 2 different Roland pedals (RPU-3 & DP-10) on MODX was unsuccessful since continuous operation is not recognized at all. On another forum, site admin verified that Yamaha's FC7 CController doesn't respond as well!

Can someone verify that this half dampening ( NOT A SIMPLE ON-OFF ) works in real world ? (a FC3A purchase is quite expensive ~ 70euros, therefore one must be absolute sure about its compatibility).

I cannot confirm whether the Roland branded pedals work or not. I can only confirm that the Yamaha FC3A is the pedal you want to use for the Half Dampering function to work on Yamaha branded keyboards. Just FYI, the FC7 is a sweep pedal, not a momentary (Sustain) Type Pedal.

You can be 100% sure the recommended Yamaha Pedals work for your Yamaha Synthesizer. That’s a no-brainer.

FC3A Half Damper capable Sustain Pedal
FC4A regular On/Off Sustain Pedal
FC5 regular On/Off Sustain Pedal (rectangular)
FC7 sweep type Pedal suitable for Super Knob, Volume, Wah Pedal Type duties.

The secret of Half Dampering is only half told by the type of pedal, it is understood as a parameter setting within the Amplitude Envelope Generator (AEG) at the Element level of the MODX architecture.

EXTRA CREDIT:
The Sustain pedal function on an acoustic piano is a bit of a misnamed function. It is not really “sustain” — it kind of delays the inevitable. The piano is in the family of hammered, struck and plucked instruments called “percussion” instruments. The initial event triggers the musical vibration, and over time, gravity and air friction inevitably end the vibration... whether or not you are holding the Sustain pedal is inconsequential, it will end.

The notes of the piano up to the G5 have felt dampers that are lifted from their resting place on the strings, whenever a key is struck. You can prevent that “damper” from falling back on the strings by continuing to hold the key or by holding the Sustain Pedal. So it is really the manipulation of the pedal that determines the dampers contact with the strings.

A player can artfully control the string’s vibration by using the sustain pedal (also called the damper pedal in some circles) and its contact with string. In other word, while pressing the pedal full down the dampers are moved completely away from the string and it rings out. By using less downward pressure on the damper pedal you can partial mute the free ringing of the strings controlling its length (duration).

Many folks have no idea that Half Dampering is not about ‘longer sustain’ but control over the lesser amounts of sustain. ...on notes from A-1 through G5.

The MODX parameters that concern themselves with Half Dampering are as follows:

[UTILITY] > “Settings” > “Sound” > Sustain Pedal

You can "know" for sure whether a MODX Performance is utilizing Half Dampering - it is an Element level edit. An Element is a like a complete synth path, it includes a Waveform (Oscillator) > Filter > Amplitude Generator > LFOs > routing to the Insert Effects and an Output.... 8 Elements can make up an AMW2 Part.

Select the Part you wish to Edit
Press [EDIT]
Touch “Elem1” along the bottom of the screen Element 1
Touch “Amplitude” > “Amp EG” > “Half Damper” On/Off and “Time”

In a piano sound that is 8 Elements you have the ability program each individually.

_ When you release a key while pressing the Footswitch fully down, the sound will decay to the Sustain Level (Decay 2 Level), according to the Sustain Time (Decay 2 Time) value. In this case, you can control the decay time between the Sustain Time and Release Time by how far down you press the pedal. However, when you release the pedal after releasing the keys (key off event), the sound will decay according to the Release Time, as if the Half Damper function was set to off.
_ When pressing the sustain pedal fully down, the sound will decay after reaching the Sustain Level (after the Decay 2 Time). When the Footswitch is not pressed fully down, the sound will decay immediately.

Dear Bad Mister,

I'm disappointed!! I asked for an answer but... you provided a comprehensive tutorial on the subject 😀 :D.

Thanks for your professionalism. To be frank the last 2 paragraphs...

_ When you release a key while pressing the Footswitch fully down, the sound will decay to the Sustain Level (Decay 2 Level), according to the Sustain Time (Decay 2 Time) value. In this case, you can control the decay time between the Sustain Time and Release Time by how far down you press the pedal. However, when you release the pedal after releasing the keys (key off event), the sound will decay according to the Release Time, as if the Half Damper function was set to off.
_ When pressing the sustain pedal fully down, the sound will decay after reaching the Sustain Level (after the Decay 2 Time). When the Footswitch is not pressed fully down, the sound will decay immediately.

... resume the true functionality of the dumpering (and is a bit confusing, i read it thoroughly), but i believe one should try this to better understand in a musical sentence. I will surely do so!!

Congrats, once again, for your effort and complete reply.

This article, although for the Motif, may help provide more context:

https://www.yamahasynth.com/motifxf-category/half-damper-function-damper-resonance-effect-and-key-off-sample

There is some additional info that may help fill in the gaps.

Thank you very much Jason!

If you think Yamaha piano is not right, then you do not understand which keyboard do you want to use. If you wish to some exact details about it, then go in deriving it to below for instruction. And thank you for creating this thread to share my knowledge with you. And i'm very glad mr. bad mister you share great information to world wide for taking guide of who can not understand it. Thank you so much for this.