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Stage piano key action and static touchweights


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[the Kawai ES110] has the same fully sampled EX piano as the MP11SE, plus 5-pin midi ports and bluetooth.

 

Please note that the ES110's EX Concert Grand sound has the same overall character as that of the MP11/MP11SE EX Concert Grand sound (note, note the SK-EX Concert Grand sound), however is less expressive due to the smaller sample memory capacity of the ES110.

 

I realise that this is unrelated to the keyboard action discussion in this thread, but wanted to clarify the ES110's sound specifications just in case.

 

Kind regards,

James

x

Employed by Kawai Japan, however the opinions I express are my own.
Nord Electro 3 & occasional rare groove player.

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I've got the Nord Electro 5HP. At only 11.4kg it's very light to carry, which is why I bought it, but I find the action rather stiff to play, unlike the RD700 which I now use at home in the studio.

 

Yamaha YC73

Korg Kronos2 61

Yamaha CP88

Roland Jupiter 8

Roland JX3P

Roland D50

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Today I added the Yamaha N1X hybrid, Medeli SP4000, another Kurzweil Forte 8, and Kurzweil PC4 to the table.

 

Although the SP4000 and the PC4 are listed as having the same action, the Medeli K6, they are noticeably different in two ways. First, the SP4000 has no gradedness, the downweights are uniform across the board. In the PC4 the keys have a high gradedness, a difference of 23 grams between the upper and lower keys. The lower keys are more heavily weighted than in the SP4000, and the upper keys are lighter than in the SP4000. The average downweight across the keyboard is about the same in the SP4000 and PC4. Second, and I don't know if this is a hardware or software difference, is the escapement. After you play a key in the SP4000, in order to play the key again, it has to first rise 7 mm. In the PC4, the key only has to rise 5 mm before being depressed again to play. This results in a noticeably greater playability in the PC4. Other than these two differences, the key actions are about the same. Both have moderate key and hammer bounce.

 

If you want to compare the PC4 action to a more common board, it's very similar to the Yamaha GHS action, which is in the P-125 and several other Yamahas. However, it's better than the Yamaha in having noticeably less key and hammer bounce. Or, it's similar to the Casio PX actions, but is slightly heavier, slightly less noisy, has lower key/hammer bounce, has a longer distance to pivot, and is a bit more playable. In the Casios, you can single-key drum easily to about halfway up the key, but in the PC4 you can single-key drum easily up to 2/3rds the distance of the key. So it's like a Casio, but quieter, heavier, yet easier to play fast passages in the middle of the keys.

 

I haven't seen a Kurz SP6 yet, which also has the Medeli K6 action -- no guarantee that it's identical to the PC4, but probably very similar.

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Please note that the ES110's EX Concert Grand sound has the same overall character as that of the MP11/MP11SE EX Concert Grand sound (note, note the SK-EX Concert Grand sound), however is less expressive due to the smaller sample memory capacity of the ES110.

 

I realise that this is unrelated to the keyboard action discussion in this thread, but wanted to clarify the ES110's sound specifications just in case.

Thanks for that clarification, I was wondering about that!

 

Second, and I don't know if this is a hardware or software difference, is the escapement. After you play a key in the SP4000, in order to play the key again, it has to first rise 7 mm. In the PC4, the key only has to rise 5 mm before being depressed again to play. This results in a noticeably greater playability in the PC4.

When talking about electronic keyboards, the feature called "escapement" specifically refers to the "notch" feel as you depress a key, and the PC4 does not have that. There is no common name I can think of that refers to the measurement you're talking about, but I agree that it is of interest. I guess I'd call it something like "minimum note retrigger height." In a two-sensor board, it is the height of the "Note Off" sensor, In a three-sensor board, it's the point that corresponds to the middle sensor (the functional difference being that, with the damper pedal NOT depressed, the note will go silent when lifted to this point on a two-sensor board, but not on a three-sensor board).

 

Maybe this is the best place for a shameless plug! Our now not-so-new new video at https://youtu.be/3ZRC3b4p4EI is a 40 minute adaptation of T. S. Eliot's "Prufrock" - check it out! And hopefully I'll have something new here this year. ;-)

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Second, and I don't know if this is a hardware or software difference, is the escapement. After you play a key in the SP4000, in order to play the key again, it has to first rise 7 mm. In the PC4, the key only has to rise 5 mm before being depressed again to play. This results in a noticeably greater playability in the PC4.

When talking about electronic keyboards, the feature called "escapement" specifically refers to the "notch" feel as you depress a key, and the PC4 does not have that. There is no common name I can think of that refers to the measurement you're talking about, but I agree that it is of interest. I guess I'd call it something like "minimum note retrigger height." In a two-sensor board, it is the height of the "Note Off" sensor, In a three-sensor board, it's the point that corresponds to the middle sensor (the functional difference being that, with the damper pedal NOT depressed, the note will go silent when lifted to this point on a two-sensor board, but not on a three-sensor board).

 

Yes, it's the notch feel, and neither of the Kurzweils have this notch feel. I had previously thought the Forte did, as somebody on a forum (not this one) stated as much, but now that I felt the board I've indicated in the table that it has no escapement.

 

And it should be pointed out we're all talking about double escapement, whose purpose (in an acoustic piano) is to reset the action of the key so the key can be played again without having to move to the top to reset itself. So using your term, the purpose of double escapement in an acoustic piano is to reduce the "note retrigger height" which makes it easier to play the same note repeatedly.

 

Edit: And, nearly all boards have this reduced retrigger height (as if they had double escapement) but only a few have the escapement notch feel of an acoustic piano. On nearly all the boards I measured the minimum retrigger height is less than 5 mm. In some it was even smaller, like the Yamaha P-515 was around 3 mm. A few were over 5 mm, and the Medeli SP4000 was one of those at 7 mm.

 

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Second, and I don't know if this is a hardware or software difference, is the escapement. After you play a key in the SP4000, in order to play the key again, it has to first rise 7 mm. In the PC4, the key only has to rise 5 mm before being depressed again to play. This results in a noticeably greater playability in the PC4.

When talking about electronic keyboards, the feature called "escapement" specifically refers to the "notch" feel as you depress a key, and the PC4 does not have that. There is no common name I can think of that refers to the measurement you're talking about, but I agree that it is of interest. I guess I'd call it something like "minimum note retrigger height." In a two-sensor board, it is the height of the "Note Off" sensor, In a three-sensor board, it's the point that corresponds to the middle sensor (the functional difference being that, with the damper pedal NOT depressed, the note will go silent when lifted to this point on a two-sensor board, but not on a three-sensor board).

 

Yes, it's the notch feel, and neither of the Kurzweils have this notch feel. I had previously thought the Forte did, as somebody on a forum (not this one) stated as much, but now that I felt the board I've indicated in the table that it has no escapement.

 

And it should be pointed out we're all talking about double escapement, whose purpose (in an acoustic piano) is to reset the action of the key so the key can be played again without having to move to the top to reset itself. So using your term, the purpose of double escapement in an acoustic piano is to reduce the "note retrigger height" which makes it easier to play the same note repeatedly.

 

Edit: And, nearly all boards have this reduced retrigger height (as if they had double escapement) but only a few have the escapement notch feel of an acoustic piano. On nearly all the boards I measured the minimum retrigger height is less than 5 mm. In some it was even smaller, like the Yamaha P-515 was around 3 mm. A few were over 5 mm, and the Medeli SP4000 was one of those at 7 mm.

 

Thank you so much for detailed review!

 

Maybe same construction but different sensors. Keyboards in SP6 and PC4 are described differently on Kurzweil website.

PC4: RPHA: Real Piano Hammer Action / 88-note, fully-weighted hammer-action with velocity and aftertouch sensitive adjustable keys

SP6: 88 note fully-weighted hammer-action with velocity sensitive keys

 

I played SP6 for a while a few months ago, and it also reminded me of GHS, but being slightly better (faster) than GHS. And also being better than Fatar TP/100 due to longer pivot, but worse than TP/40. I don't remember sensors behaviour, but I think it was classic two sensor. You write about escapement, I think the action in SP6 / SP4000 is two sensor (I think the action in SP6 and SP4000 can be identical or very very similar), but the action in PC4 can share the same geometry, keys design etc, but three instead of two sensors and "hammers" with some weight grading. Should be quite fine action in PC4. I haven't played PC4 nor SP4000.

Yamaha P-515, Korg SV-2 73, Kurzweil PC4-7

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I find this thread to be my favorite of the year. I"ve realized the up and the down weighting are my prime concerns, not the sound.... The Steinway 155 with its 63 downweight and 24 upweight is the clear winner so far. It"s no wonder I get painfully sore after a couple of hours playing on a digital piano. The are shockingly over weighted. I do best on a 1900 nine foot Mason and Hamlin grand with a downweight of 45 and up weight of 33 It"s about the weight that Horowitz liked his piano.

 Find 660 of my jazz piano arrangements of standards for educational purposes and tutorials at www.Patreon.com/HarryLikas Harry was the Technical Editor of Mark Levine's "The Jazz Theory Book" and helped develop "The Jazz Piano Book."

 

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On nearly all the boards I measured the minimum retrigger height is less than 5 mm. In some it was even smaller, like the Yamaha P-515 was around 3 mm. A few were over 5 mm, and the Medeli SP4000 was one of those at 7 mm.

The Korg SV1 has a particularly low retrigger point, despite being two sensor. The Casio PX-5S retrigger seems high, despite being three sensor.

 

Maybe this is the best place for a shameless plug! Our now not-so-new new video at https://youtu.be/3ZRC3b4p4EI is a 40 minute adaptation of T. S. Eliot's "Prufrock" - check it out! And hopefully I'll have something new here this year. ;-)

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Horrrowitz downweight type action:

Horowitz type action

 

' Vladimir Horowitz's last Steinway D had characteristics something like: 44-45g downweight, 30-32g upweight.'

 Find 660 of my jazz piano arrangements of standards for educational purposes and tutorials at www.Patreon.com/HarryLikas Harry was the Technical Editor of Mark Levine's "The Jazz Theory Book" and helped develop "The Jazz Piano Book."

 

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I find this thread to be my favorite of the year. I"ve realized the up and the down weighting are my prime concerns, not the sound.... The Steinway 155 with its 63 downweight and 24 upweight is the clear winner so far. It"s no wonder I get painfully sore after a couple of hours playing on a digital piano. The are shockingly over weighted. I do best on a 1900 nine foot Mason and Hamlin grand with a downweight of 45 and up weight of 33 It"s about the weight that Horowitz liked his piano.

 

Here's another interesting story:

 

"In 1891, the House of Steinway brought the the famous Polish pianist Paderewski to America to show off his playing (and their pianos). In Paderewski's memoirs, he mentions having problems with the Steinway piano because he was accustomed to playing European pianos, which had fairly light actions. Compared to those European pianos, the Steinway had a very heavy touch. Of course, the Steinway piano also had heavier strings under higher tension than the European instruments, and was capable of a more powerful tone. But Paderewski found the Steinway action almost intolerable, because of the amount of effort required to play it. The problem was ultimately solved by Steinway providing Paderewski pianos with actions specially 'lightened' or adjusted to his preferences."

http://www.pianofinders.com/educational/touchweight.htm

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Jazz+: I learned to play on a very light Knabe square grand -- and as a teenager and in my early 20s I practiced several hours a day, highly repetitively, to learn Mozart and Beethoven sonatas, and never developed tendinitis. I was often frustrated at lessons because my teacher had a heavier Chickering and things that I found easy to play on my Knabe were impossible to play on her Chickering. I loved that Knabe, still do.

 

Now that I practice mainly on digitals, I still don't have tendinitis, but I have calluses on my fingertips that I never had as a kid.

 

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Thank you so much for detailed review!

 

Maybe same construction but different sensors. Keyboards in SP6 and PC4 are described differently on Kurzweil website.

PC4: RPHA: Real Piano Hammer Action / 88-note, fully-weighted hammer-action with velocity and aftertouch sensitive adjustable keys

SP6: 88 note fully-weighted hammer-action with velocity sensitive keys

 

I played SP6 for a while a few months ago, and it also reminded me of GHS, but being slightly better (faster) than GHS. And also being better than Fatar TP/100 due to longer pivot, but worse than TP/40. I don't remember sensors behaviour, but I think it was classic two sensor. You write about escapement, I think the action in SP6 / SP4000 is two sensor (I think the action in SP6 and SP4000 can be identical or very very similar), but the action in PC4 can share the same geometry, keys design etc, but three instead of two sensors and "hammers" with some weight grading. Should be quite fine action in PC4. I haven't played PC4 nor SP4000.

 

We'll have to keep wondering about the SP6 as I don't foresee being able to play one any time soon... Yeah I was disappointed after I played the Medeli SP4000 a few weeks ago, could not believe Kurzweil could have chosen such an inferior action. But my worries were unfounded, their modifications really turned it into what is arguably one of the best actions under 30 pounds ... maybe best, along with the somewhat lighter Kawai ES110. Now I'm back to seriously considering a PC4 :-)

 

Edit: well, best if your primary use is the pianos .... for Hammond it's obviously far from ideal.

 

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Here are some plots of average key downweight against total keyboard weight, for each board and action, color coded. The total keyboard weight was jittered slightly at random so that the names don't overlap too much. Overall the downweights do predict the total keyboard weight, but there's a lot of variation around the line with some interesting patterns, suggesting the ways these actions have been modified for different markets. Will add some comments in a separate post.

 

http://www.stewartschultz.com/Music/boards%20color.png

 

http://www.stewartschultz.com/Music/actions%20color.png

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One point of realism in weighted hammer action in an acoustic piano is the feeling that you're flipping a hammer when you press the key: this means that the initial downward force to start the key/hammer moving is highest, then drops very low after the hammer is flipped and the first escapement kicks in, then increases again as the key nears the floor of its travel and the second escapement is triggered. So the downweight is high at first, drops down to near zero after a few millimeters downward travel, then increases again before the key hits bottom. Call it the "downweight dip" caused by the hammer flip. In contrast, if springs are responsible for the downweight, there is no downweight dip and the key feels less like a hammer flip and more like a sponge, regardless of the downweight.

 

With that in mind, a few observations about these plots:

 

1. There are some big differences among boards with the same actions, I think caused by modifications of the hammer weights and spring tensions for different markets. For example, the Roland FP 60 versus Roland FP 10, both with the PHA-4 action. The FP 10 has heavier downweights than the FP 60 yet is 6 kg lighter overall, a big difference between two boards that have very similar chassis. I'm thinking that the FP 10, marketed as a lightweight entry-level board, has lighter hammers to reduce its overall weight, and that lost downweight is replaced by springs. This is why its action feels more spongy than the FP 60, and its downweights are higher though its overall weight is less. Another example: the very large difference in downweights between the Korg Krome and Korg Kross (both NH), again with the higher overall board weight in the keyboard with the lower downweights. Again, I think the hammer weights in the Kross were reduced, and the lost downweights replaced by springs, giving the Kross more of a spongy and less of a hammer-flip feel, but allowing a very low total weight. Also within the Yamaha GHS and the Korg RH3 actions there's notable variation in total weight, with the more entry-level piano boards the lowest weight, but hardly any variation in average downweight. Again, this might be caused by modified hammer weights and spring tensions to match. The result is that there are two types of lightweight boards: those with high downweights caused by high spring tension (the spongy feeling boards) and those that leave their downweights lighter and have more of a hammer flip feel (Kurzweil PC4, Kawai ES110).

 

2. Some boards have a very high total weight, not predicted or needed by the key downweight. Obvious example is the Kawai MP11SE, which has roughtly the same downweights as the Casios, yet weighs almost 70 pounds, three times the weight of the Casios. Hard to see why this is necessary. Another example is the Kawai VPC-1, which is just a controller with no buttons, knobs, or display at all. Why would it weigh 28 kg, ten kilograms higher than the Yamaha CP88 which has roughly the same key downweights, plus banks of control panels and displays? Strange.

 

3. Sure is some intense competition for the low weight niche down there at around 12-15 kg with downweights of 70 g. About 12 boards massed down there at that spot.

 

 

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Vladimir Horowitz's last Steinway D had characteristics something like: 44-45g downweight, 30-32g upweight. These digital actions are darn heavy in comparison. Japanese design teams don"t dare go against the status quo or the boss. I wonder if they are even aware how heavy they make these things. It"s no wonder I can"t play my best on them and get fatigued.

 

http://www.stewartschultz.com/Music/Selection_999(535).png

 

 Find 660 of my jazz piano arrangements of standards for educational purposes and tutorials at www.Patreon.com/HarryLikas Harry was the Technical Editor of Mark Levine's "The Jazz Theory Book" and helped develop "The Jazz Piano Book."

 

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How do measure distance to actual pivot? Isn"t the pivot behind the fallboard back under the casing? Therefore not accessible?

 Find 660 of my jazz piano arrangements of standards for educational purposes and tutorials at www.Patreon.com/HarryLikas Harry was the Technical Editor of Mark Levine's "The Jazz Theory Book" and helped develop "The Jazz Piano Book."

 

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How do measure distance to actual pivot? Isn"t the pivot behind the fallboard back under the casing? Therefore not accessible?

 

Yeah it's not accessible to measure directly -- I did it by using geometry based on the angle of the key as it is depressed, shown in this post:

 

https://forums.musicplayer.com/ubbthreads.php/topics/3019541/re-stage-piano-key-action-and-static-touchweights#Post3019541

 

[bTW I responded to your PM]

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How can I measure the pivot distance of a key?

 Find 660 of my jazz piano arrangements of standards for educational purposes and tutorials at www.Patreon.com/HarryLikas Harry was the Technical Editor of Mark Levine's "The Jazz Theory Book" and helped develop "The Jazz Piano Book."

 

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How do measure distance to actual pivot? Isn"t the pivot behind the fallboard back under the casing? Therefore not accessible?

 

Yeah it's not accessible to measure directly -- I did it by using geometry based on the angle of the key as it is depressed, shown in this post:

 

https://forums.musicplayer.com/ubbthreads.php/topics/3019541/re-stage-piano-key-action-and-static-touchweights#Post3019541

 

[bTW I responded to your PM]

 

I think the most precise measurement is always to open the housing, find the pivot point and measure the length from the key front to pivot point. Sometimes it is hard to find proper pivot point like in GHS action where the keys are bending and "there is no axle or hinge".

In your measurements there is a difference in pivot length in same keybeds like Roland FP90 and RD2000 which share the same PHA50 and its pivot length is 22 cm. Same for Korg RH3 in D1, SV1 and Grandstage, they can't be different. I don't believe that CP88 has 22 cm pivot length, CP1 had about 20,5 cm (21 cm key length). It's impossible that NW-STAGE in CP4 has 23 cm, NW-GH3 has 22 cm, NWX has 20 cm. They all are based on the "ancient" GH Yamaha keyboard, which was also called GHE (Graded Hammer Effect) in the past, used in the P-range, CLP, MO8, same keys in Motif. Montage 88 keys versions but balanced not graded. I also believe that all full sized Rolands have 22 ccm, despite the Hybrid Grand which is based on the same design but longer. Nord Stage 3 88 - in your table 21 cm, Nord Piano and Kurzweil Forte 19 cm. It's impossible, they are all Fatar TP/40 variants! Same keys, different weight hammers.

There is standarization in keybed parts production. The manufacturers usually share the same construction, changing sensors, keytops, adding wood, but the dimensions change is the last on the list of improvements, because of the injection molds for the plastic parts manufacturing. The differences in results in the table are due to the measurements innacuracy, I think. The longer the real pivot length, the less accurate results because of the smaller vertical angle between the two key positions. Anyway, your measurements are helpful when there are no actual photos of key action, drawings, nor measurements.

 

By the way, your results seem to confirm my theory that CP73 BHS keys are same as GHS keys, but weighting is different. From marketing perspective it's "newly designed, similar to Montage/Motif feel". I'm not so sure, but unfortunately I haven't played CP73. I can even see the short pivot on the youtube videos. Anyway, CP73 seems to be very good instrument for its features and weight!

 

I gained some info about pivot lengths based mainly on the photos from the other piano forum and also interpolation from the key action drawings (for Fatar or Roland Grand Hybrid, also some Kawai) and posted this into our polish forum Muzykuj.com.

Here's the link:

http://www.muzykuj.com/forum/showthread.php?tid=2287

 

BUT..... the good feel of the keys is NOT ONLY the pivot length. The convenience of playing is a combination of the key static weight, key inertia, key dip, the loudness, the dynamics, timbre changes in various dynamics ranges, repetition (fastness), etc. I moved from Roland action Ivory Feel-S (which was simplified - without wood colored plastic core - PHA III, 22 cm pivot length) for Yamaha NWX (ca. 20,5 - 21 cm pivot length). The action is heavier but to me feels lighter TO PLAY, because of other factors.

 

Yamaha P-515, Korg SV-2 73, Kurzweil PC4-7

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By the way, your results seem to confirm my theory that CP73 BHS keys are same as GHS keys, but weighting is different. From marketing perspective it's "newly designed, similar to Montage/Motif feel". I'm not so sure, but unfortunately I haven't played CP73.

I've thought the same, and wondered if what is really meant by "similar to Montage/Motif feel" (compared to CP88 or GHS as in the MODX) is that they are balanced rather than graded. But it's conjecture.

 

Maybe this is the best place for a shameless plug! Our now not-so-new new video at https://youtu.be/3ZRC3b4p4EI is a 40 minute adaptation of T. S. Eliot's "Prufrock" - check it out! And hopefully I'll have something new here this year. ;-)

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I missed any mention of this earlier in this thread, but measuring static up weight and down weight on an acoustic piano should always be done with the damper pedal depressed. With the damper the AP action will feel lighter, but your DP action won't, it doesn't have separate damper weights.

 

So the (correctly) measured touch weight of an AP will always be lower than that of a well calibrated DP, thus the two values are not really comparable.

 

Also, the feel of the action will depend very strongly on the moment of inertia of the action.

 

When I last checked our Steinway D at work, it had an average down weight of 49 grams (ranging from 37 in the treble to 55+ in the bass); a mean up weight of 31 (range: 23 - 38 grams). And an average balance weight of 40 grams. Even though these touch weights seem all over the map, this D is very easy to play and control for long periods of time without fatigue.

 

Dennis

 

 

 

 

Dennis
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I think the most precise measurement is always to open the housing, find the pivot point and measure the length from the key front to pivot point. Sometimes it is hard to find proper pivot point like in GHS action where the keys are bending and "there is no axle or hinge".

In your measurements there is a difference in pivot length in same keybeds like Roland FP90 and RD2000 which share the same PHA50 and its pivot length is 22 cm. Same for Korg RH3 in D1, SV1 and Grandstage, they can't be different. I don't believe that CP88 has 22 cm pivot length, CP1 had about 20,5 cm (21 cm key length). It's impossible that NW-STAGE in CP4 has 23 cm, NW-GH3 has 22 cm, NWX has 20 cm. They all are based on the "ancient" GH Yamaha keyboard, which was also called GHE (Graded Hammer Effect) in the past, used in the P-range, CLP, MO8, same keys in Motif. Montage 88 keys versions but balanced not graded. I also believe that all full sized Rolands have 22 ccm, despite the Hybrid Grand which is based on the same design but longer. Nord Stage 3 88 - in your table 21 cm, Nord Piano and Kurzweil Forte 19 cm. It's impossible, they are all Fatar TP/40 variants! Same keys, different weight hammers.

 

I agree, but data is data. I measured these as carefully as I could with the tools I had, and reported the results honestly. I think this gives a fairly good idea of the uncertainty in the measurements. A better method would have been to make the measurements several times for each board, and then report the average. But, that's just too much work. it's painstaking to get a good estimate of the angle that the key makes when it's depressed. I think the data is good for showing some broad overall differences.

 

 

There is standarization in keybed parts production. The manufacturers usually share the same construction, changing sensors, keytops, adding wood, but the dimensions change is the last on the list of improvements, because of the injection molds for the plastic parts manufacturing. The differences in results in the table are due to the measurements innacuracy, I think. The longer the real pivot length, the less accurate results because of the smaller vertical angle between the two key positions. Anyway, your measurements are helpful when there are no actual photos of key action, drawings, nor measurements.

 

Yeah if you do the calculus of errors, the longer pivot lengths have the larger error, because the number in the denominator is smaller, so small variation in the denominator will have a large proportional effect.

 

By the way, your results seem to confirm my theory that CP73 BHS keys are same as GHS keys, but weighting is different. From marketing perspective it's "newly designed, similar to Montage/Motif feel". I'm not so sure, but unfortunately I haven't played CP73. I can even see the short pivot on the youtube videos. Anyway, CP73 seems to be very good instrument for its features and weight!

 

Interesting, had not thought of that, but it definitely makes sense!

 

I gained some info about pivot lengths based mainly on the photos from the other piano forum and also interpolation from the key action drawings (for Fatar or Roland Grand Hybrid, also some Kawai) and posted this into our polish forum Muzykuj.com.

Here's the link:

http://www.muzykuj.com/forum/showthread.php?tid=2287

 

BUT..... the good feel of the keys is NOT ONLY the pivot length. The convenience of playing is a combination of the key static weight, key inertia, key dip, the loudness, the dynamics, timbre changes in various dynamics ranges, repetition (fastness), etc. I moved from Roland action Ivory Feel-S (which was simplified - without wood colored plastic core - PHA III, 22 cm pivot length) for Yamaha NWX (ca. 20,5 - 21 cm pivot length). The action is heavier but to me feels lighter TO PLAY, because of other factors.

 

I think the pivot length is very important though -- the other factors of the key mechanism are easy to duplicate -- static weight/inertia are easy to manipulate, and key dip. The tough one though is pivot length, because of the demand to have a lightweight, compact instrument. That's one thing that makes the acoustics feel lighter and more responsive everywhere on the key. I could feel it right away when playing the Steinway D, with 28 cm pivot length -- it felt wonderfully easy and responsive even though having high downweights. There is no digital that I could find with an apparent pivot length greater than 23 cm. I think the market would be very strong for a board that combined just a few easy features -- a pivot length of 25 cm, completely hammer-weighted (no springs), with realistic static weight/inertia for example. It's surprising to me that such a board does not exist. The closest board to that though is the CP4/CP88, which is the one design that seems to get the most positive reviews from experienced players.

 

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I missed any mention of this earlier in this thread, but measuring static up weight and down weight on an acoustic piano should always be done with the damper pedal depressed. With the damper the AP action will feel lighter, but your DP action won't, it doesn't have separate damper weights.

 

So the (correctly) measured touch weight of an AP will always be lower than that of a well calibrated DP, thus the two values are not really comparable.

 

Also, the feel of the action will depend very strongly on the moment of inertia of the action.

 

When I last checked our Steinway D at work, it had an average down weight of 49 grams (ranging from 37 in the treble to 55+ in the bass); a mean up weight of 31 (range: 23 - 38 grams). And an average balance weight of 40 grams. Even though these touch weights seem all over the map, this D is very easy to play and control for long periods of time without fatigue.

 

Dennis

 

 

 

 

Jazz+ pointed this out. The reason I chose to measure with the pedal up is because 1) what's important is that the same method be used for all boards, because we're comparing these boards to each other, not to the literature values on acoustics, and 2) I think it's a bit more informative to know the downweights when the pedal is up, because the maximum downweights are more of interest than the minimum downweights, esp. for people with tendon issues.

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I think the pivot length is very important though -- the other factors of the key mechanism are easy to duplicate -- static weight/inertia are easy to manipulate, and key dip. The tough one though is pivot length, because of the demand to have a lightweight, compact instrument. That's one thing that makes the acoustics feel lighter and more responsive everywhere on the key. I could feel it right away when playing the Steinway D, with 28 cm pivot length -- it felt wonderfully easy and responsive even though having high downweights. There is no digital that I could find with an apparent pivot length greater than 23 cm. I think the market would be very strong for a board that combined just a few easy features -- a pivot length of 25 cm, completely hammer-weighted (no springs), with realistic static weight/inertia for example. It's surprising to me that such a board does not exist. The closest board to that though is the CP4/CP88, which is the one design that seems to get the most positive reviews from experienced players.

 

Yes, you're completely right. It's far more control on dynamics when the pivot length is longer. Also the force difference between two ends of the visible part of the key is smaller. Keys are just levers.

 

For Yamaha GH variants up to NWX, piano purists note that in these actions the "hammers" (which are actually metal rods) movement isn't independent from the keys movement - the "hammer" is connected with the key permanently, so after releasing the key being hit, the hammer falling down pulls the key up. There is impossible to "bump" the returning hammer by hitting a key when playing realy fast repetition which is possible e.g. in Roland PHA actions, where the hammers are free and independent from key movement. Some of the piano purists say, if so, they are not a real hammer actions but (heavy) weighted synth actions! But I think, due to those "compromises" these actions are so fast, responsive and not sluggish! They are considered as some of the fastest for a stage piano with good feel (Fatar TP40 is also fast, but much less realistic). The best way of thinking for me is "if it feels good, it's good no matter of its construction".

 

At the moment there are some digital piano actions that have pivot lengths over 23 cm. They are Grand Feel, Grand Feel II, Kawai Novus' action, Roland Grand Hybrid, Yamaha Grand Touch (CLP-675, CLP-685). They are up to 26 cm (Roland Grand Hybrid, I read somewhere that Kawai Novus has similar length) which is nearly like full sized concert grand you mention. Altough, pianos with this actions are not slabs in most cases but console pianos.

 

You can put info in the table that the values of pivot length are calculated, not directly measured. I really appreciate your work and I'm happy that this thread exists!

Yamaha P-515, Korg SV-2 73, Kurzweil PC4-7

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Yes, you're completely right. It's far more control on dynamics when the pivot length is longer. Also the force difference between two ends of the visible part of the key is smaller. Keys are just levers.

 

Yes as we all know from our kid-playing teeter-totter days, a small kid can lift any big kid no matter how heavy, as long as the big kid is sitting up near the pivot.

 

For Yamaha GH variants up to NWX, piano purists note that in these actions the "hammers" (which are actually metal rods) movement isn't independent from the keys movement - the "hammer" is connected with the key permanently, so after releasing the key being hit, the hammer falling down pulls the key up. There is impossible to "bump" the returning hammer by hitting a key when playing realy fast repetition which is possible e.g. in Roland PHA actions, where the hammers are free and independent from key movement. Some of the piano purists say, if so, they are not a real hammer actions but (heavy) weighted synth actions! But I think, due to those "compromises" these actions are so fast, responsive and not sluggish! They are considered as some of the fastest for a stage piano with good feel (Fatar TP40 is also fast, but much less realistic). The best way of thinking for me is "if it feels good, it's good no matter of its construction".

 

Yes if it feels good that's all that matters -- but there's so much subjectivity and differences in opinion about what feels good (some people don't like the CP4 action at all, some think it's superlative) that I wanted to see if there is any objective number that seemed to capture what people were praising or complaining about. Not easy to quantify! But, I learned a lot and still am.

 

At the moment there are some digital piano actions that have pivot lengths over 23 cm. They are Grand Feel, Grand Feel II, Kawai Novus' action, Roland Grand Hybrid, Yamaha Grand Touch (CLP-675, CLP-685). They are up to 26 cm (Roland Grand Hybrid, I read somewhere that Kawai Novus has similar length) which is nearly like full sized concert grand you mention. Altough, pianos with this actions are not slabs in most cases but console pianos.

 

Yeah I was referring to the slabs -- the hybrids and consoles often do have higher pivot lengths. Interestingly, I did measure the Kawai Novus in the table, and my pivot length measurement for that one was 25 cm, calculated from the key angle. So, pretty accurate!

 

 

You can put info in the table that the values of pivot length are calculated, not directly measured. I really appreciate your work and I'm happy that this thread exists!

 

Thanks! I wanted to edit the original post to explain all the stuff that I added later after peoples' suggestions, but apparently the editing function disappears after some time interval. But ironically I can edit the table itself! So that's a good suggestion, I can clarify that length is calculated.

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Fabulous job!!!

 

I would like to see the specs of the Dexibell Vivo s9. Cause it is the only fatar tp400w keybed in the market.

 

Would you please list out the key travel data for each key?

 

I wonder how do you measure the Dist to pivot??? Just open each model??? Just got it from reading through the entire threads.

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