http://www.dailymotion.com/video/x583zxs

The weight used is 65 grams. Across the full range there are about half a dozen or more keys which are stiffer than their neighbours to the left and right - also some keys not so stiff are markedly looser to play than others.. Nothing to do with the 8 zones of graded hammer weight.


Am I being fussy? Have other HP or LX series users experienced the same thing?

The response of my dealer was that the Roland tech he spoke to had not encountered a problem like this in 25 years - this response made me feel like I was being fussy..

I guess the real question is, how does it affect your playing? If it's noticeable when playing a piece of music, then it should be addressed.

+1, can you notice it?

One question is what delta is between the stiffer and looser keys. At some weight every key will be slightly heavier or lighter than its neighbors within the same graded zone, but are we talking about one extra gram to get it to drop, or ten?

heh well, it has been thirty years since my last lesson, and we bought this piano just over a month ago.. so pretty much very much a beginner. I did notice weaker fingers and seemingly stronger fingers doing scales, but it kept moving so to speak - did not occur to me my part of my difficulty playing evenly was due to our brand new piano at first.

Every time I hit one of those stiffer keys, the finger feels weak, but then also the ones adjacent I play too loudly - like a delayed reaction.

no gombessa, its not to do with the grading - notice in the video that a stiff key will have a loose one to its left, and to its right.. this holds true for all of the stiffer keys, the distribution of which is pretty much random across the keyboard, with a little grouping

When the little man you can hear in the video has gone off to bed I will do some more measurements and note the actual down and upweights.

That`ll be beneficial to one`s playing technique . . .not. It couldn`t happen with Yamaha`s GHS because there isn`t a pivot pin!
Any better keyboards around which also use cantilevers instead of pins?

without having measured the actual total down and up weights for all the keys, just eying the pha-50's build and reading some posts on previous Roland mechanisms I got two possible causes - in older pha there seems to be use of a white grease here n there - possibly some of it got someplace it should not be, or too much of it. And at the front below the keys there are two guide rails - one with a strip of foam on top, and one with foam on top and below, catching a 'hook' that extends from the bottom of the key halting its movement up - if the foam on this rail is not properly aligned, it might rub against the straight bit of this hook and hinder its progress a little - since the stiff keys also have a little less bounce to them, this seems likely to me.

You misunderstood my question, let me rephrase:

Assuming this is happening within the SAME graded zone, what is the delta in weight needed to drop the stiffer keys?

I agree with Morodiene that the key question is whether you notice the difference while playing, but knowing the delta at least helps quantify the issue.

This definitely seems like an issue with the action then. Have your dealer send out a tech to take a look at it. Send them that video link if they need a little bit of coaxing to prove that it's not in your head.

If my acoustic had that issue, it would mean it is poorly regulated. Obviously it's a different issue in a digital, but it is not something you should expect from any piano.

A faulty action, surely?

I got another response from the dealer - he mitigated his earlier one a little..
It's going back to Roland for a while.

Gombessa I will map the action's down and upweight later and see if I can find the zone boundaries - since some of the stiffer keys are quite close to each other, sometimes separated by just one or two looser keys, and the PHA-50 has 8 zones, my guess is no - as for the delta its 10 grammes give or take a gramme..

Peterws - there isn't a pivot pin in the PHA-50 - it's a cantilevered design ; the triangular extrusion near the middle of the key pushes down onto a catch that then folds the force to the hammers - the sensor is underneath the cantilever point very nearly activated by one end of the arm that translates the action to the hammer. Is why I am thinking its either the guiderail hindering the action, or dollops of grease in the wrong place, or perhaps the axle on which the hammer and sensor arm throws..

The two keys I did some finer weighing on, one required a further 10 grammes to match its neighbours to the left and right, and another stiffer key further up the the same octave required 8. Listening to the action the loose keys you can hear fine mechanical contact noises, and the stiff ones a slight rubbing.. I think the guiderail is the culprit. The stiff keys also have far less bounce when released.

Eying the video of the PHA-50 action frame by frame I noticed right in front of the keys there are pins coated in a light gray thin material.. my thinking is these are guidepins in the front of the keys which are covered in teflon possibly?
https://youtu.be/--yVVAtjcUo?t=37

hmm btw how do I add in a picture from my pc - all I find in the message dash is insert image then only choice to insert an http?

Thanks for the feedback everyone - feeling less fussy ^^

Thanks, I think you answered the most important question when you said that playing the stiffer keys is noticeable to you and makes you misplay the adjacent keys as well. And IMO 10g static weight difference between keys in the same zone is very high, hopefully your dealer and Roland can help fix the issue.

being such a novice at play at one point I was like hm well it must be me who am I to complain/stumble about such a small difference..

Roland will be coming to our house - the detailed description I gave, gave them confidence they could repair in situ - yay =]

Excellent! Let us know how that goes!

Roland once made a house call to replace the action sensors on my old RD-700 stage piano. It was out of warranty but the fee was pretty reasonable and the guy did all the work on my kitchen table.

^^ well I will be sure to have my phone at the ready to take some pics of what this tech will do to our 605's innards - very interested to see inside

I've worked in tech support in the past.

"No sir, we've never encountered such a problem before."

*Glances over a the stack of 47 devices with the same problem, sent in within the last week*

Mostly, the only time tech support will tell you something is a known problem is when it becomes so well-known and so bad that it will actually be fixed outside of warranty, as to save the company's reputation.

You're in the Netherlands, and Roland will come to your home to fix this?

You don't even *begin* to know how happy I am to hear this.

Really.

Getting the LX-17's console up the stairs was a very precarious undertaking because they're narrow, steep, and have a very nasty bend in them.

The only time I would *think* of moving the LX-17 down those stairs again is if I move, and then I'll need to think of some way to do it safely, as I don't have the packaging material anymore.

And, AFAICS in this video, you're not fussy. Those keys are too different in weight to be played reliably. Good luck with the repair.

^^ I can imagine Y ours is a sweet burden though Falsch! I did come to understand not all repairs are done at a client's home though..

I suppose the best way would be to buy a roll of bubblewrap and ductape it round the 17 very tightly.. Lemme know in a couple years when you're ready for an upgrade - we got a roll of bubblewrap

The three things that might need maintenance on a piano are the pedals, the keyboard, or, maybe, the speakers. If there are no design flaws, I expect the electronics to hold up for 20 years at the very least. There are digital organs around older than that.



Yeah; the people who delivered it were intent on taking it out of the packaging because they thought it would be easier.

You don't have any grip, and that PE stuff is slippery as heck. It came too close to going wrong, to be honest. I estimate the console at around 60 kg. The entire piano weighs around 87.

To get the console up the stairs, it had to be first carried up the first flight. Because it's longer than the bend can accommodate, it was necessary to stand it up onto its side (on a very thick and large pillow), and shove it in front of the second flight, with its underside towards the stairs. Then tilt it, carry it up the stairs, and then do the stand-up/shove/turn routine again to get it into the room.

(I have one of those apartments with the living spaces on the second floor.)

If *I* had to do it, I would have left the console in the box, and cut out hand-holds on the left and right, or make two holes in the bottom or something, so you can actually grip it properly and stand it upright and turn it without fear of damaging it.

If I have to move this again, I will definitely package it up into a 20cm thick layer of bubble wrap, including the left and right sides.

====

By the way, I would not upgrade from a 605 to the LX-17, as it's the same piano; or you would want it for the better speakers and the cabinet.

If I can get used to the sustain pedal I harped about in two topics already, I don't see an upgrade for at least 10 years, as I'm of the opinion that at this point, it's the best digital upright piano there is. I'll probably skip at least one, but probably two generations.

(Or more, if Roland keeps driving its prices into the stratosphere.)

Yes it's all about the speaker systems, and larger cabinet with better resonances and better apeaker placement inside ^^ The only reason we went for the 605 was, well cost was one issue lol Too many other money pits this year.. and the lx7 made no sense.

I was also very pleased the 605 came in two boxes - 70's drive-in house here, with the livingroom upstairs as well ^^

I want to play a 605 sometime. I really disliked the LX-7's sound system. The 605 also has 6 speakers, but of a different sort and placement. I wouldn't be surprised if I would like it better than the LX-7. If I do, I might actually come to the conclusion that the 605 would have been enough for me, but I h have no way to test one in my neighborhood.

With regard to the money, I agree. The LX-7 matte black costs €3499; the PE costs €4099, and the LX-17's price has been increased from €4995 to €5199. If It hadn't been for the lower German price in September 2016 to provide me a stronger negotiation start, the discount at the dealer (transferred from the CLP-585, of which I bluntly told him I wouldn't want to be found dead with in the same room), the free high-end bench, and the fact that I had was able to sell an 18 month old Hammond clone for quite a good price, I wouldn't have been able to afford the LX-17.

Because all of the above, my outlay for the LX-17 was minimal. I've been lucky in that regard. (However, I bought the Hammond clone by first selling a different Hammond clone.... and I bought that one by trading in... and so on.)

XD

It does.. at first I thought it could have been due to the surroundings but when I came home and read some of the comments from users here on the LX7 I concluded it wasn't. The 7 has larger volume cabinet but none of the measures to control unwanted resonances like the 17 does ( the extra speakerbox enclosures inside ) and while the 605 has a slit all along the length of the piano to allow sound to come out, the 7 has two tiny slits way on the left and right, and that opening behind the music stand..

If we do stick with our 605 beyond its warranty period, I think I am likely to open it up and modify the sound system a little.. At the very least add bracing inside to lessen cabinet resonances, add some dampening material ( polyester wool ) to even out the sound as it too, versus the 17 with its top lid and more direct higher frequency sound, has a little bit of a belly heavy sound.


Am very interested in what I will actually find in there when that Roland tech swings by to attend the key issues

So the 605 also sounds bottom-heavy? I hope it's not as bad as the LX7. I wonder why they did that with that piano.

The LX7 sounded like a home organ to me, with most sound coming from below the keyboard. I thought the LX7 to be very bad compared to the uprights I've tested in the same store.

The LX17 has larger speakers, more speakers, two of which in the top, in a different setup, different crossovers by necessity, and a lid that opens up. I hoped the LX17 would sound better than the LX7, and it does.

I'm now not even convinced I'd ever *want* an acoustic piano, to be honest... I deem the LX17 to be as good as a Kawai K-500 (as far as I've been able to test), although it obviously has a different sound character.

The one thing that the LX7 does better is the music stand. It can accommodate an A3 music binder much easier than the LX17 (or any piano with the stand on top, for that matter). Same goes for the CLP-585 and Kawai CS8.

The 605 also comes with a 10 year warranty (if you registered it), so you'll have to wait a long time to make your modifications.

While some people call it a gimmick because 'DP's don't ever break, if they don't break in the first three years', and because it's not transferable, making you keep the piano for 10 years, I still think it shows confidence on Roland's part. I can *definitely* see people buying something like an LX17 (or even a 603) and keep it for 10 years.

No not so much bottom heavy - more pot bellied ^^ Its the cabinet resonances mostly - I've looked up some DIY repairs done on older Roland models in this price range and....not one bit of bracing inside, not one shred of dampening material either, no tape or special shaping of the panels to seal the rest of the cabinet =|
Wíth some bracing and the proper amount of dampening, a loudspeaker can go from terrible to pretty decent.


The LX7's bottom heaviness is from the larger bass speakers I suppose, and the lesser amount of middle and high frequencies ( the drivers for which are identical to the 605) able to escape the cabinet through its far smaller and more divergently placed openings which still don't really radiate towards the player directly much at all.

Eying the sparse LX17 internals info out there, I suspect it too has zero bracing or dampening =S

When I have time I will do a measurement of the frequency response of the HP605 using a sweep - suspect it shows some serious spikes around 100-200hz range and lots of little ones going up the ladder all cabinet resonance.

I don't know about that; my knowledge with regard to speaker systems is limited. I only know what I like (which is a mostly flat frequency response, with a tiny bump in the bass below 100 Hz) or don't like (anything out of balance). I'm just glad the LX-17 sounds as I hoped it would sound.

When comparing the speaker systems, the Roland site says this:

603: 30Wx2, 7Wx2, Cabinet: 12cm, Near-Field: 5cm, Spatial: 5cm
LX7: 30Wx2, 7Wx2, Cabinet: 25cm, Near-Field: 5cm, Spatial: 12x8cm, in speaker box

So, the LX7 has both larger bass speakers, and larger spatial speakers (I assume these are used for the higher notes and resonances), and it has the same near-field speakers for the sound effects (damper noise, hammer fallback, etc).

On paper, it looks like the LX7 is just a more powerful version of the 605, with comparable sound characteristics, but that may not be true in practice, because of differences in the construction of the cabinet.

The LX17 is completely different:

25Wx2, 6Wx2, 6Wx2, Cabinet: 25cm, Near-field1: 12x8cm, Near-Field2: 5cm, Spatial: 12x8cm.

I assume Roland has moved the spatial speakers to the top of the cabinet (aided by the raised lid), and moved some of the frequencies from the cabinet speakers to the extra 12x8cm near-field speakers above the keyboard. (The LX7 and 603 don't have those speakers.)

That would definitely explain the difference in sound signature between the LX7 and LX17.

ah yes - more differences then I remembered. I just poked a flashlight into the 605 - zero dampening and bracing inside.
From what I can see the two 5cm speakers are above the 605's fallboard that slides into the cabinet, the nearfield 5cm are below the fallboard, and those 12cm bass drivers are radiating out from underneath.

Yes - if the 7 had a similar top lid setup, it would be a better in between model than it is now.. but probably with too little to differentiate it from the 17 in the lineup.

Ah well - you get what you pay for ^^

IMHO, having *any* sound but bass coming from below the keyboard is... not smart, because all sounds but the bass are directional. A bass sound just 'is', while the higher frequencies can be easily located by the ear.

The only instrument I know that outputs sound from under the keyboard is the home organ, and even those sound better when connected through large standing speakers, or large studio monitors and a subwoofer.

yep - in the 605 though those midrange drivers also output through the slit of the slide in fallboard - same is true for the 7
basically it bounces off the keys at you ^^

*update*

A nice tech support came by and examined the PHA-50 keybed and confirmed he felt the difference in touch weight while playing, but after much looking could not find a cause for it at all.. Took out some of the problem keys and examined the underlying mechanism, removed some of the grease, added some and no discernible difference resulted. He was stumped - said he had not come across this issue ever..
Unfortunately when he took out the fallboard he nicked the side of the finish as well -_-

Want to post some pics but how do I include pics from local harddrive and not http? I do not see an option to do this in the message menu?

That would require that pianoworld host your images. I think the easiest thing is to upload them to imgur.com or put them in a shared Google Drive or Dropbox folder.

Pianoworld can easily host your images for you. Actually, it's the preferred way to post images. See here:

http://www.pianoworld.com/forum/ubbthreads.php/topics/2248307.html

Ah, didn't notice that before, thanks JoBert. Still seems a bit too involved to me compared to a one-click upload to Imgur!

Honestly, that's quite odd. You'd think it would be easy to isolate the problem--take off the keys and depress the hammers and see if the weight difference is still there. Swap the key with a different one and see if the problem follows the key. Swap the hammer with a different one in the same grading zone and see if the problem follows the hammer. If the problem never travels, it's likely something with the keybed frame...

He did not have the kinds of tools to do this with him ; mostly electrical repair tools and parts..
And while the keys come out easily enough, the hammer actions are grouped and I think one can only swap those around once you have completely removed the entire bed.

Ah, well that's 1) too bad, and 2) nonetheless sounds like something a DP tech should be prepared to do...

I can understand the actions being in key groups, but are the hammers themselves really captive under the bed? They should be free-hinged, right? Oh well.

What are your next steps?

It was an interesting view inside there though; sorry for the lack of descriptions with the pictures - editing the post just shows the image path not the image itself so shuffling back and forth is a bit of a bother.

It looks like there are several little amplifier boards distributing the sound to the various speaker units. Zero dampening material inside, not even the oftentimes deployed 'cups' over the down firing bass drivers..

The top of the 605 comes off with the row of screws near the top lid at the back ( 4 in all ) then the top slides forward a little, then there is one plug you have to pull free and the top comes off.

To be able to lift out the keys the control face was unscrewed and layed on its back behind the keybed.

Keys lift out easily but the hammer mechanisms are grouped in keys of darnit I forgot to take notes ^^ I think 8 keys. The hammers are metal and grading is per zone of 8 or so keys ( again should have taken notes )

https://www.pianoworld.com/forum/ubb...HA-50_/_HP605_internals.html#Post2612888 for larger pictures.

In short - my suspicions of the cause were not correct - the rails were properly aligned, the foam on these rails were razor straight, and clearances of the keys appeared to be all in order..

Next steps - the tech was going to contact Roland to ask for the tolerances of touch weight differences.. He was going to report back there was nothing within view he could do on the spot basically.

They are free hinged, but to get at them and remove them, you have to remove all the keys, then unscrew the whole assembly, then lift it out and then take apart the hammer and escapement actions..

Goss,

Did you try playing the HP605 with the top off?

We did ^^ but it doesn't improve things lol; in the pics you see two 12cm "bass" drivers ( you can see their magnets ) and the two 5cm nearfield drivers ( the ones mounted at a 45° angle ).
To take the top off you got to unplug a molex connector which unplugs the added 5cm "spatial" drivers which are mounted to the underside of the top.

Its easy enough to fit some dampening material without voiding the warranty - there are no stickers breached or anything and its just 4 screws and unplugging that molex and sliding the top towards the front of the piano a little and you're in.

I think though with those other speakers not boxed in as with the LX17 it will just muddy up the sound more than benefit it if one just props up the lid without doing any other more drastic work..

I had a Yamaha P120 with keys leaning to the sides. It was a manufactural known problem that occured after months.
As a pianotuner/technician i opened the P120 and gave it a very good look. A tiny plastic part on the back of the keys caused unwanted tension to the left part of the keys,causing it to lean sideways just a tiny bit.
By removing a tiny bit of the plastic i was able to make it work again.
I bought 5+ new keys eventually when i wanted to sell it and told the buyer who couldn't really care , because i sold it for little money.

Observing the PHA-50 , i can see several aspects that could influence the feel/grading.

In my opinion, on the contrary to claims made by the brands, also plastic parts aren't 100% identical after installation in a larger action containing many parts.
That 's why some keys in my P120 leaned over and others did not.Exchanging similar keys underlined that impression....it was the plastic keys the had extremely tiny variations in shape !!!
Exchanging some plastic keys ,only the white fully plastic keys solved the problem.....(so the problem was the shape of the plastic that had deformed just a tiny bit ) In real piano's the brands Rippen, Kawai and Yamaha experimented with plastic parts in acoustic actions during the seventies, because plastic couldn't ''work''. Well they were wrong and abbandonad that whole idea....back to the wooden actions
Kawai does use some graphite parts instead of wood now, but that is not plastic.

Bottom line...i don't believe in hybrid actions that don't need any regulation ever........i believe nothing that is used so intesively as a piano action works flawlessly for decades.
They can minimise all sorts of influences, but sometimes you end up with a unit that underlines the imperfections of real world materials.

Curious what the final outcome of your PHA-50 is going to be ...

Thanks for raising my spirits Pianistje (sarcasm )
I fear you are right. Funnily enough Rippen actions were a topic of conversation when the tech and I got to talking about the joys of plastics XD

Thanks for the update Goss, and for sharing your pics.

I expect dewster would have appreciated a sharper image of the main PCB, but he has been MIA for some time now, unfortunately.

I wonder if the smaller board in front is the Bluetooth controller?

Cheers,
James
x

oh I will add some more pics - the guy was on a schedule and I did not want to keep him so I switched to 4K video - I imagine screencaps of that will yield pretty good stills

Got a call from the nice tech - he ordered new side panel for the one he made the little dent in so that's something ^^

He is dropping by a Roland dealer with some touch weights and is going to check a few PHA-50 actions for himself to see wether or not this behaviour of heavy keys is 'normal' for the action.. This slightly worries me as a reaction to be honest.
This was after he had a talk with Roland Netherlands.

map of all the heavier keys marked with white stickers. Some blacks included though I did not map those completely.
50% of the heavy ones do not depress at all with the weights on them while their neighbours to the left and right do - the other half depress a little ways but not as much as their neighbours.

The middle C key as an example - I used a stack of 16X € 0,10 rolled in some tape ( adds 1 gramme ) total weight of the coins is 16X 4.10gr= 65,6 grams plus the 1-2 grams of weight of the tape around them. The difference in touchweight is an additional 1 € 0,50 which is 7.8 grams.
Then further up the octave a G requires one € 0,50 and 1 €0,20 coin to get this key depressed as far as its neighbour to the left and to the right which totals a touch weight difference of 7.8 + 5.7 = 13,2 grams.
The additional touchweight needed varies across the keyboard, and from measurements I did earlier - before the middle C required two 50 cent pieces totalling 15,6 grams.

http://www.rubinghscience.org/surv/euroweights1.html

Kawai used an ABS composite plastic before they started adding carbon fibre. And ABS can be very stable, it's not like your lego bricks fail to fit decades down the line! The key thing is manufacturing precision.

What is often referred to as Carbon fibre/graphite is still essentially plastic too and the polymer part of kawai's latest actions is still ABS from what they say. The full term tends to be along the lines of carbon fibre reinforced polymer (or CFRP).

Yep - injection moulding with carbon fibres is easier, more exact and cheaper than laminating carbon fibres with other resins such as polyesters or epoxy by hand or vacuum process.

https://www.youtube.com/watch?v=vBhkLuXZzCc example with glass fibre for those who just love how its made =]

http://kawaius.com/technology/carbon_fiber-technology.html some details on Kawai's carbon fibre reinforced action parts

Maybe I'm wrong, but AFAIK, it's normal for keys to become heavier on the left, and lighter on the right. So, touch weight wouldn't be the same across the entire keyboard?

Read my posts again Falsch ^^ There is no smooth curve of touch weight - there are spikes and dips of 7-15grammes all across the board regardless of graded action. Middle C as example its neighbours to the left and right 65 grams touchweight. Middle C requires 7+ grams extra relative to its neighbours.

Further up the octave and beyond there are some that require 12-15 grams more than their left and right neighbours..
Further UP as in where it is supposed to get lighter =_=

Hope you get it all sorted Goss. Interesting about the weights you mention, that is actually leaning quite towards the heavy side in acoustic land as I am learning. I think someone here also did that for the Gf2 or Gf1 action and it came somewhere like 63 grams on middle C, again leaning towards the upper scale of recommended heaviness for static touch weight. Interesting though as a comparison I only measured middle C on my casio once, it began to give way around 55 grams, but it felt rather easier to play on the roland in terms of speed, the ones I tried in the shops anyway, less friction issues and a lighter dynamic touch no doubt compared to my Casio (I suspect).

Very nice keybed on the rolands I thought, lovely to play, assuming it all works as it should of course, sounds like you got the lemon :D, there is no way that kind of variation is acceptable I think, whatever feedback they come back with in terms of tolerance, it is well outside what is acceptable and needs to be repaired one way or the other.

My Casio has also developed some uneven keys here and there, but I live with it for now, it's pretty minor, it may be going and replaced sooner than later anyway.

On the carbon fibre age in pianos, it is coming, Kawai use it in parts of the action, there are others stretching the idea much further. For anyone interested

http://www.phoenixpianos.co.uk/phoenix-carbiano/

There are some with just the soundboard too, and from what I can tell on the basis of a recordings at least they sound darn good and promising. A downside I can see developing, the beauty of wood gives each piano its tone and unique quality, while some variations will be possible with hammers strings etc and other part of the design perhaps, they'd likely all sound very much the same otherwise, would we want that ? There again, I doubt wooden pianos will never go away for a long time yet.

Have fun

Hi Alex
Yes the PHA-50 is a tad on the heavy side initially - I got used to it pretty quickly though, and despite the issues I still like our Roland ^^

Wow, that was a lót of work to make.. A friend of mine is a shipbuilder - wood, resins and carbon kevlar and such - this took some people quite some time and a lót of prototyping before they got to this stage I'll bet. Was a good read in bed last night - thanks for this =]
Do find it sounds very clear - they do mention due to the lesser sound absorption of the carbon the upper registers especially sound out much more ; one of those recordings of it had me going for the volume controls hitting [-] more than a few times ^^

Their other designs are interesting too - especially the new way they mount the strings so their soundboards don't lose their crown - good stuff

*update*

Well, disappointing. The tech did some tests with other PHA-50 equipped key actions, and found similar discrepancies with all of them - he tried 3 pianos. He contacted Roland, and they responded this issue cannot be fixed.. Within tolerances they said.

C4 and c8 sharing the same touch weight is within tolerance -_-

I'd imagine most acoustic pianos have a similar discrepancy unless meticulously maintained. Part of the grading felt during playing is in the inertial weight which is presumably still there since the c4 hammer is heavier than the c8 one.

So there is relevant issues with the PHA-50 action... And I just purchased the LX-7.

I would not fret too much Monnet - the tech mentioned he found several PHA-50's with some keys exhibiting the same behaviour, but not nearly as many as mine.. Some other owners here feel absolutely no issues in theirs.

None of the pianos are immune to mechanical issues - just reading for example some Kawai owner's troubles with RMIII or Grand Feel on the forum here.. But its not that áll the Kawais have these issues or if they do, have them with the same severity.

Goss, sorry to hear the response. I wouldn't have thought it's within tolerance for keyweighting to be that different between zones.

What's the plan, are you going to try to escalate the matter? Just live with it? DP actions are so mechanically basic that I'd be tempted to troubleshoot the issue myself if it happened to me. The root cause cannot be much more than some source of excess friction I would think?

I don't know Gombessa =/ I am going to mull it over this weekend. Haven't talked about it with my wife yet, but two options, well three. come to mind. One is accept it - maybe the friction lessens with wear of the action. (The technician said his Roland contact told him that if the problem is still an issue in one year's time then they would be open to offering another solution.. While he did not mention wear could be a leveller here, I infer it from this remark) Two is don't accept it and try another HP605 or LX and hope there is less of this issue or none of it present. Three would be to open it all up and go over the parts with a micrometer / caliper and see what I can do myself. It would be fairly exacting work - filing the surfaces would need to be done dead straight or there would be issues with alignments.. and there are 25 keys to tend to.