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The Roland Hybrid Grand looks like it may very well be 26cm. Does anyone have a link to an actual measurement?

Here are a few more I've seen (including some acoustics), but of course a lot is missing...

Is that key length or pivot length. If so really useful. Highlights just how short the 18 cm pivot length of the Casio is.

The shortest, the Yamaha AG series at 23 centimetres is a very large improvement on the Casio. But the Kawai MP11 at 24cm is longer and far cheaper.

Thanks for this.

this might help...




Sorry I didn't want to dismantle the piano, I don't want to ruin the warranty
(forgot to mention, this is GF2)

@Faiz Thanks for the photos, the first photo is easy to interpret, whereas I am having trouble understanding what is being measured in the second.

the second photo was intended to show the other end of the ruler. I can't take the key stick and the pivot in single photo since opening the cabinet will void the warranty, there is enough gap under the cover to fit my phone so I can take a pic.
sorry for that vague photo.

I typically measure from the center of the balance pin (I'm not sure if that's actually the right point), but it looks like it could be a 5-10mm difference depending on how others measure (i.e., the front or back of the balance pin slot).

GF2 should be identical to GF1 in terms of pivot length afaik, so it should also be 24-25cm. It looks like you're measuring 14-15cm? Which is odd....you can see my OP with Grand Feel 1 full key length and pivot point measurement here: http://forum.pianoworld.com/ubbthreads.php/topics/2688852/mp11-grand-feel-key-and-pivot-lengths.html

My measurements are from the center of the (white key) balance pin to the edge of the white key, including the overhanging lip.

The pin isn't the pivot point on the GF action. The balance rail (or its equivalent on the GF) is where the key pivots, so it's a few millimetres closer to the player. IIRC it's less than 24cm when measured this way.

On a folded action, the centre of the pin is the pivot point. In practise, it's easier just to measure to the centre pin on both types. A few mm doesn't make any difference unless the keys are really short anyway.

I had the chance of comparing the PHA50 Hybrid on a Roland LX706 side by side with the PHA50 on a HP 603 and I was surprised on how similar they feel even when playing close to the fallboard. Perhaps. My guess was that the difference of angles in percentage is small so that an amateur player like me can't perceive that.

Is the action of the LX706 now called "PHA50 Hybrid"? Because I thought officially, it was called "Hybrid Grand Keyboard" action, at least in the USA. Is it being called "PHA50 Hybrid" in Portugal/EU?

In my case, I'm not that advanced, but felt a big difference between the PHA50 and the "Hybrid Grand Keyboard" action in the LX708, especially when playing both black & white keys near the fallboard. The "Hybrid Grand Keyboard" action was much better for me than the PHA50, and it was much easier to play near the fallboard and with control.

Kawai ES100: 21 cm

Thanks @JoeT that is useful.

For the extreme case of playing right at the fallboard with the Casio as the reference (exposed key length of 15cm).

Casio Privia/Celviano AP series with a 18cm pivot length.
The required force to play the key is 6 times than at the front of the key. Leveraged movement will be 6 times faster than at the front of the key. Regulation is difficult.

Going with the Kawai ES100 with a 21cm pivot length, and assuming the same exposed key length*.
The force to play the key is 3.5 times than at the front of the key. I think regulation could still be a little hard.

Lets go for the 24cm pivot length assuming the exposed key length* since there are various more expensive models with this.
The force to play the key is 2.66 times than at the front of the key.

* I think it is ok to keep to this assumption. 15cm is fairly typical for exposed key length but even if it varies you don't aim to play at the fallboard just somewhere along the length of the key.

That can't be right. The first photo shows the 5cm mark in the middle of the black keys, the second photo shows the same 5cm clearly way behind the black keys. It doesn't look as if the ruler in the first photo was in the same position as in the second, so the two photos together don't really show a useful measurement, as was probably intended. (It rather looks as if the first photo simply measures the visible length of the keys, with the end of the ruler at the fallboard, and not at the balance pins, as the second pic might suggest.)

So that's what it is!
I came across that picture yesterday when googling Casio actions. I knew it was Kawai, but wasn't sure which one. Thanks for that!

Watching this one with interest. It'll still be a while before I can buy anything, but will learn from this.
The Casio CPS-7 I'm currently fighting with has a pivot at a bit under 14cms. Even the Roland PHA-4 I tried felt like heaven after it and I guess that 18cms would be quite an improvement after it too but hardly ideal.
Out of curiosity, I downloaded the Schubert Impromptu 3 (in Gb, fingers near the fall-board etc.), and tried it out. It is possible (and tiring!) to play the notes, but.....

Wow, that must mean the exposed part of the key is just under 14cm with the pivot-point immediately behind the fallboard. You literally cannot play at the fallboard.

It's quite basic. It looks the keys are formed on a plastic moulding with a bar that sits horizontally under the casing with the keys themselves attached to it, the plastic at the attachment being thinner and I assume flexing. The leading edge of the key is about 13.8 cms from the 'fall-board' and the key itself is about 13.4 cms, the difference, approx 4mm, being the thinner part that I assume flexes and is visible between the key and the fall board. I'm not really sure how long the thinner part continues underneath the casing (fall-board) really, so of course it could be that I've underestimated the length a bit. It looks like the end of the key when fully depressed (not the plastic attachment) near the fall-board goes down by about 1mm.
I wonder if anybody understood that explanation - or was interested, really, come to think of it
It's good exercise for the fingers, maybe.
Actually, I bought it many years ago (the 1990s I think) as a portable to take on holidays so it's fine for the casual use it was intended for. The fact that it is doing duty as a 'piano' these days is due to the demise of my acoustic and the uncertainty of my status here in France thanks to BREXIT (goes away muttering....I think I've moaned enough about that on PW!)

On pivot points, does anybody know what the measurements for the Kawai 'Grand Feel Compact (GF-C)' are? Looks shorter than the Grand Feel and I think is on the CA48 and CA58.

Yeah, looks like it's somewhat between the RM3-Grand 2 (18-20cm) and Grand Feel 2 (24cm).

That was really useful to me. I am just trying to get context of the range. The key travel on my Casio AP-470 is less than 2mm with 15cm of exposed key and a 18cm pivot distance. I'll keep my fingers crossed for you and me re Brexit. Like you I can't satisfy my desire for instant gratification and get an expensive DP with a decent action and pivot length. I really like my Casio otherwise, the action works well and I like how it feels as long as you can stay away from the "fall-board" and I think it produces a good sound by matching the speakers and speaker placement along with its amplifier and combines them well with its sound generator for its price range.

Thank-you. Hope all goes well for you too.
On my acoustic the key length from fallboard is about 15 cm including the lip, depression at fall-board about 4mm (it's difficult to measure completely accurately).
* edited to add. The pressure needed on the Casio CPS-7 is possibly partly due to the fact that it uses rubber thingies under the keys to return them.