Piano World Home Page Forums Our Most Popular Forums Digital Pianos - Electronic Pianos - Synths & Keyboards Is the GH keyboard generally heavier or lighter than GH3?

My last digital was a CLP-411 and I loved the feel of it, even though the technology is quite outdated now. I haven't had opportunity to play on a GH keyboard and GH3 side by side. Can anyone tell me which is heavier? I've had tendonitis in one wrist so am actually more drawn to a lighter keyboard. Thanks!

The overall weighting on both is very similar. Only the GH3 has slight weight change from left to right across the keyboard range in four zones. There will be no material difference between the two for your special needs.

Great... thanks!!

I think the biggest difference between the GH and GH3 is the sensors. GH is a 2 sensor system and GH3 is a 3 sensor system. The extra sensor improves response, especially on quick repetitions. But the actual action is very similar.

Both GH and GH3 are graded in weight from bass to treble (GH = "Graded Hammer").

+1 on Geoffk

The mechanics and weighting of the GH and GH3 are identical. They share the same part numbers for the weighting elements (what Yamaha calls the Hammer Assembly) and spring. The key is only different in that the contact point is shaped differently to accommodate three contact points in stead of two.

The third sensor on the GH3 action is functionally equivalent to the repetition lever on an acoustic grand action, allowing faster repetition without fully releasing the key or allowing the damper to touch the strings.



The left contact is the *new* Key On contact, the center and right contacts have the same function as on the GH: velocity sensing. As you back out of the key, right and center contacts are opened but the left contact remains closed until the key is further up.

Alden, thanks for that description and photo.

Approximately two years ago, someone who said that he had the tech manual for Yamaha's Natural action posted that it uses a mechanism that's different from the Graded Hammer actions. By any chance have you had an opportunity to examine a Natural action?

FogVille - with the exception of the keys themselves and a couple of guide and limiter parts added to the key frame to adapt to shape differences on the key's under side, the GH3 and NW actions share the same mechanical and contact parts.

Alden, thanks so much for that info. Touch is a recurring topic on this forum. Based on the post which I cited, I expected that there would be more differences.

I'll look for images of those 'boards, so that I can internalize your description.

Alden, thank you for this explanation and useful photograph!

Cheers,
James
x

These are pictures of an older GH action, but the form factor and basic mechanism remains the same.


The metal part on the lower left is the Hammer Assembly. This one is for the heavier bass end of the action. The length of the portion that's bent back towards the front decreases as you move up into lighter zones.


(circuit board is towards the player)

Hope this helps with the visualization. As with all DP actions, *how* they do it is interesting but ultimately unimportant. Its the result that counts.

Alden,
In my brief testing of a GH3 equipped model (the CLP-340), I found that when slowly releasing a key, the sound would terminate when the key had reached about 50% of it's travel.
If I understand you correctly, the third(additional, new) sensor on the GH3 action is actually ABOVE the 50% point, closer to the top of the travel. Do you know how this third sensor is actually used, exactly? I would have expected that once the 50% return had been reached, a new note could be played, without the previous note being terminated - just like a grand piano. The third sensor near the top makes a lot of sense to me, because this also matches a grand piano - a real grand doesn't damp the strings until the key has nearly reached the top. (again, if my understanding is correct). Having the third sensor near the top would, in theory, improve legato playing. Now, another Pianoworld member, who owns the P-155, which only has the "GH" action, said that his model also terminates the note at the 50% return. This tallies with your description - the new sensor is further up, so naturally the GH action MUST terminate at the 50% point.

EDIT: I have an idea of how it might work. Maybe for partial returns, the repeated notes will have no velocity sensitivity, or different velocitiy sensitivity. The fact that the note terminates probably isn't terribly important - it won't be that noticable when playing rapid repeats. (it may still be noticable in some situations though, such as a slow partial repeat - slow partial repeats still work on a real piano, according to a reply to this question I asked over on the piano tuner/technician's forum)

I briefly tested a Casio PX-130, which also has three sensors, and it seemed to behave properly (or at least, how I would expect it to behave). I tested it in a very non ideal environment, though, so take my result with a huge pinch of salt. (it would be good if someone who actually owns one of the new Casio range could confirm my result)

Can you shed any light on my observations of the GH3 action?

Greg.

On my GH based P155 the note terminates (is damped) when the key raises back to 50%. At that point I can replay the note.

I think having a sensor above the 50% point lets the note continue to ring until you get to about 80% raise but you can replay in after 50%.

So the difference between GH and GH3 should be that on a GH3 you can reply the note without damping it first. But in both cases (1) all notes are velocity sensitive and (2) the amount of raise before you can replay is the same.

In the GH3 as in the GH, both measure velocity by meassurment of the time between the lower two sensors I think the top 80% level sensor on the GH3 only controls the damper and both cases all notes repeated or not would use the two lower sensors

I think the GH3 is doing colser to what a grand piano would do but each key action would allow for just as fast a repeat rate


To the OP: (in case you are still looking) If you are looking for a lighter key action in a Yamaha console piano then I think you are going to want a YDP140. This piano uses GHS action which is very much lighter but otherwise is very much like the lower end CLP.

Chris,
I agree, except I am not observing that behaviour. On the CLP-340, which does have the GH3, the notes terminate at 50%. It matches your P-155 exactly. I tested in a store, in a rushed fashion, so I could be completely wrong. However, I did use a tyre tread depth gauge to measure the distances, and I did the measurements multiple times. 10mm total travel - 5mm note termination travel.
I could not make the notes retrigger without there first being a termination. (this is what I COULD do on the Casio - a retrigger without a termination) As I said in the other thread, when I tried rapidly repeating, restricting the motion in the manner you suggested, I was less certain that it was not working - there is a some possibility that it was working when playing rapidly.

I agree though - it appears that the third sensor will not make any difference to the repeat rate - it should do two things: improve legato playing, and b) produce more authentic sounding partial-release repeats.

Greg.

I can in fact get the GH3 to retrigger. (at last! However, the retrigger point is so very close to the cutoff point that I can't help wonder about how effective this could possibly be. Both points are indeed very close to 50% travel. (btw, this is the third different example of a GH3 piano that I have tried).

I tried a GH version after that, and I really could not get it to retrigger no matter how hard I tried. (as expected)

I then tried a Kawai grand, and the two travel distances were much better spaced out - the dampers didn't completely damp until the key was almost at the top, and the partial-repeat travel was down below 50%.

Finally, I tried a Young-Chang grand. I didn't try to ascertain the distance between the two points, however I noticed that the dampers damped at a travel further down, closer to 50%.

I only tried a single note from each grand, so I can't say how consistent they were across the keyboard. (same goes for the Clavinovas, I suppose)

Greg.

Now, repetition without full release (That means with 50% release) was already possible with the GH keyboard.

To improve repetition speed at pianissimo level it is required to reduce the blow distance at an acoustic piano.

Equivalently, for a digital, it would be neccessary to reduce the distance between those 2 contacts that are used to measure the velocity.

Ok, I think I know why they dont do this: This would mean to measure shorter switching times and this would mean more precision in manufacturing and faster processors...

Peter

Agreed, understood.



Yes, this seems very plausible to me too. There might also be a more mundane reason - Yamaha didn't want to completely redesign the keys for the three-sensor system, simply to amortize manufacturing costs between the two versions.

Note that I think the Casio sensors are also quite close together. (the top two I mean - not the bottom two) I am very curious now to try a Roland PHAIII action, to see whether the switchpoints are spaced out more evenly.

All this aside, I'm glad that repetition lever functionality is being added to digital pianos - great progress.

Greg.
p.s I've deleted some stuff from my initial reply (I felt it was redundant)

Looking at the design, I wonder whether the reason the top(new) sensor isn't higher up is due to concerns about mechanical tolerance? Looking at the way it works, perhaps there is a risk that the top sensor would simply not trip at all, if the action isn't very carefully regulated.

Note that I don't know for sure that the top sensor should be higher, but from what I have read about acoustic pianos (both uprights and grands), I suspect that it should be. (higher than my measurements to date, anyway)

Greg.

Some day they will sample key resistance and inertia from well liked grand pianos. Just like they sample the sound now. Then they can use electromagnetic force actuators under the keys rather then weighted hammers. Then not only could you exactly replicate the "feel" of any piano but the DP would "know" the force applied to every key continuously and the height of the damper key depth could be changed on the fly. The same keys could have an organ touch for the organ voice and synth action with aftertouch saxophone , flute or guitar and the like and then a Steinway or Yamaha grand feel it you wanted. DPs have a long, long way to go.

I have read some technical descriptions about acoustic pianos.
According to these the damper should not be adjusted too high,
because that would mean that staccato play wouldnt work, because the damper has some sluggishness.

They recommend to acivate the damper at 50% of keypress depth.
In german they have the word "Halbgang" for this behaviour.

So, if at the old GH keyboard the upper contact was at 50% and the lower contact at 100% then they have to use 40% for the dampercontact in order to mimic this behavior in the GH3 keyboard.

BTW. It might be clearer to label the contacts as "damper contact" 40%, "early contact" or "start contact" 50% and "end contact" or "blow contact" at 100%, because the location of the contacts is different eg. for Yamaha and Fatar and Kawai keyboards. It is not the location, it is the purpose and the time that matters.

Of course I think it would be much better to have the damper contact at 50%, the start contact at 90% and the blow contact at 100%, but that would mean to measure 5 times faster and to have 5 times better mechanical precision and possibly this could prevent the usage of cheap bubble contacts. So that would cost a lot of money.

best,

Peter

I agree. And if real time is an issue, do the scan with a cheap FPGA.

Then again, these guys won't pony up for a couple dollars more of sample Flash, even in the high-end stuff, so I guess that's out.