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In an attempt to balance the desires (not demands) of my instructor to have an acoustic piano at home (which isn't currently viable), I've been looking into the mechanics of the piano actions and the synthetic implementation with digital pianos.

Lessons are taught on a Steinway grand piano, so the bar has been set high. Upon further reading, it seems that not all DPs have escapement designed into the action, as well as double escapement (a feature of grand pianos, which in general, isn't available with acoustic uprights).

With that, is there a list (or perhaps someone here can discuss and help to generate the list) of current DPs that have escapement and double escapement designed into their action?

As I'm going to have to use a DP, I'd really like to hone in on an appropriate digital piano action that is a bit more synergistic with the lessons on the Steinway grand.

Thanks for reading and I look forward to any information and/or discussion on the topic of escapement and double escapement.

Cheers!

What is the escapement feature in key actions?

I wonder if there is any significant importance of the DP escapement mechanism as a whole(Kawaii RM3, Roland PHAIII, and such)

I know what it is but being a student of classical piano for 10 years (uprights+grands) I don't even remember a piece where I was aware of it. I'm not sure if the majority of classical piano players who are not educated in the DP tech arena ) could answer such a question.

There are things with higher importance when considering a DP, like connection to the sound, depth, tonal variance (timbre change), sympathetic resonance (pedaling), key resonance (keys held), maybe coating (ivory-like surface and such).

I think majority of piano players can play ppp without any problems regardless with of without the escapement which is a technical/mechanical necessity after all in 'ordinary' pianos.

(Still I loved the escapement on the Kawaii CN33 )

I would definitely consider the V-piano first if you can afford $5,500. It has the best response and sound in my opinion you can get from a digital piano and the fake ivory is pretty neat. Next on my list would be the AvantGrand series followed by my CLP990 which is an old model however it uses real wooden keys and hammers and has the same action as Yamaha's $250,000 grand piano's of the time. Yes I have seen it as a Clavinova repairman came to the house and opened it up. It is the only Clavinova that had it set up that way. It garnered a $5000 premium in price as well over the other CLP900 line of the time and used a completely different sample set as well with 5 layers and each not sampled separately. The Avantgrand looks to be the same action but instead of hammers it has metallic sensors on the ends and much newer technology making it sound even better than any previous CLP. Both my CLP990 and the Avantgrand are capable of very fast repeatable notes (double escapement). So is the V-Piano (albiet better at it). Which is why I recommend it over the others since it is not as heavy feeling. I truly believe I can play more accurately the quicker passages with the V-Piano in my opinion than my 10 year old CLP990 and Avantgrand which I did get to play a couple of times now. The CP1 is very good as well and another option.

That is where at the last moment the hammer disconnects from the key and continues to fly on it's own momentum until it hits the strings.

"escapement" is a term for the mechanical parts that enable this feature. But in English "escapement" is not confined to pianos. It is a general term used in mechanics. Mechanical clocks have a feature like this too where a mechanical system comes apart briefly to allow free movement.

The only piano like this I can think of is the Yamaha Advent Grand. It uses a real wooden piano action fro a grand piano. All other digital pianos simulate the grand action using much simplified construction.

For example the double escapement system on a grand pinao is there to allow you to play a repeated note without need to fully lift the key all the way back up. That is the reason of the rather complex double escapement system. But, on a digital piano the key height is senses with electrical switches so one does not need many small bits of wood. Digital pianos with three switch/sensors can allow you to play a repeated note without need to fully lift the key all the way back up. So you get the effect you are looking for but with a mechanically simply system. Likewise other parts of the grand piano's action are simulated with with simpler mechanics.

Look at some of the Roland keys and Kawai too. Make a trip to the big chain music stors and try a Roland RD700 or FP7-f and KawaI MP6 and MP10. See which key action you like. That key action will be re-used in many other models of piano. The chain stores are good because they keep many brands under one roof.

Here, terminology is getting the better of us. Escapement is like ChrisA describes, a moment where the linkage is broken to allow free movement. Both uprights and grands have escapement. "Double escapement" is the design feature in grands that allows for faster repetition, a shallower reset, and by necessity, the little catch or bump partway down the keystroke is felt.

On a DP, "escapement" is simplified marketing terminology really trying to describe that little catch associated with a grand piano's "double escapement" design.

So in acoustics, upright has single, grand has double. In digitals, the maker can either simulate the upright (no bump) or the grand (bump).

Thanks. Learning more and more!

DPs that have a '3' or "III" or "triple" in the name of their key action will most likely have three position sensors per key and therefore (if it is implemented well) should have the ability to behave more like an AP with double escapement (i.e. easier to do fast reps & note doesn't damp between reps). For example: Roland has "PHAIII", Yamaha has GH3, and most if not all Casios currently being manufactured now that are not toys have three sensors. I believe an exception to this rule is Kawai RM3, which is not a triple sensor action. Huge caveat: you should test these yourself to see what impact, if any, the third sensor (or lack thereof) actually has on playing.

DPs that say their key action has "escapement" have a simple mechanism that makes it feel somewhat analogous to the hammer slipping off the actuator. I think it's a piece of rubber or something. For the Roland "PHAIII with escapement" you only really feel it when playing the key slowly, and it is pretty subtle. That's the limit of my experience.

There's a fair bit of misinformation above so proceed with caution.

There are two aspects to consider:

1. The physical simulation of the escapement (a slight click or moment of additional resistance part of the way down the key stroke).
2. The ability of the action to recognise and articulate fast repetitions.

Three examples for you:

Kawai pianos with RM3 action: some (not all) of these pianos have the simulation of the click but do not have the sensor arrangement required to articulate the fastest repetitions. Eg: MP-10, CA-93.

Yamaha GH3 actions and NW (but not NW stage) actions: they have the sensor arrangement that allows the fastest repetitions but do not simulate the physical feel of the escapement. Eg: Most Clavinovas and many other Yamahas.

Roland PHA-III actions: these simulate the physical feel of the escapement AND have a sensor arrangement allowing the fastest repetitions. Eg: RD-700NX, V-Piano, FP7F, HP-307.

But as others have said, there are perhaps more important considerations.

Good luck,

Steve

I agree with you 100%. I suggest going to the stores and trying each out yourself before making a decision if possible. If it is not possible, then take our word for it here and you shouldn't be disappointed with any of the top choices from the top brands. However most agree the Roland seems to be the overall winner if not by a small and personal margin of taste.

Interesting to read. When I played the CA-93 against some yamahas it was definitely noticeable that the yamahas had better repetition (eg when playing very fast inverted mordents). However even on the Kawai action it was much easier to do these fast ornaments than on the mostly upright acoustics I am used to playing. However little control I put into it, on the yamahas all the notes would come, so I thought the Kawai would make a better piano for practicing.

While it's true that escapement is often a subtle effect you would not even notice during normal playing, there are certain times when you play very slowly and softly and it becomes very noticeable in that case. Take for example the beginning of Chopin's Nocturne 20 used in the DP midi playback thread - if you don't feel the escapement playing that on a Steinway then I suppose you probably won't miss it on a DP.

The double escapement system in grand pianos is simulated in DPs by the slight feeling of resistance ('bump') just after pressing the key down, before the complete 'give'.

If you're having lessons on a grand, it's worth having on the DP you're practising on, so that the feel is similar, though there're other things on a real grand that cannot be mimicked on any digital, like the lighter keyweight when the sustain pedal is down (which disengages all the dampers), and the way the whole keyboard shifts when you press the una corda pedal down.

The double escapement feature on grands allows for very quick note repetition (even when the key is still partially depressed) and very fine control of ppp which cannot be achieved on uprights. In DPs, this is achieved electronically by the number of sensors. If you aspire to play works like Scarlatti's Sonata in D minor, Kk 141 or (much more difficult) Ravel's Alborada del gracioso and/or Scarbo, all of which requires very fast repeated notes, you'll need this feature in your piano, whether acoustic or DP.

Bennevis,
FWIW, yes, just about everything you say matches my understanding. (although I think it's just "escapement" - not "double escapement" that produces the bump feeling - they are two different things, as was stated earlier in this thread). I've gotta get to an upright to test this for myself!

HOWEVER, I think it would be wrong to assume that every DP that has a tri-sensor action would automatically be better than every DP that does NOT have a tri-sensor action. For example, there may be other more important factors that come into play.

My "cheap" Casio PX-330 has a tri-sensor action, and I'd be a bit surprised if a concert pianist could play those example works better on this DP than a very good 2-sensor DP. (however, just maybe, with enough practice..... ;^)

Greg.

I agree with that. I do not find I can do repetitions faster on a tri-sensor Privia than on a good quality 2-sensor DP. Heck, I can do them fastest on a 2-sensor unweighted action!

The acoustic piano effect that the tri-sensor Casio does permit you to do is, when playing softly/slowly, you can lift a key up a little bit, and press it down again to retrigger it again at a softer volume, without having the effect of the damper fall in between the two triggers (i.e. no silence between note triggers, even when not using the sustain pedal). It's cool that it works, but I'm not sure how many pieces require that you to be able to do it.

Anotherscott,
Agreed, however, more importantly, it allows fast and soft playing - especially trills. As I've stated in the past, my piano tuning book makes a point about soft trills. It allows the piano player to trill with less effort - the fingers simply do not need to be lifted as high. This replicates the behaviour of a real grand piano, which is what this is all about.
All this assumes that the action has similar mechanical dynamics to a real piano, of course. (thinking about it, even on an unweighted action, the limiting factor for trills may in fact be the ability of the pianist to lift their fingers high enough for a repetition?)

However, I'm thinking that 2-sensor DP designers may be able to place the sensors in positions that result in an overall performance that is very nearly as good as a 3-sensor action.
I know that some DPs have the top sensor at the 50% return point, whereas my piano tuning book says that the dampers on a real piano damp when the keys are very nearly at the top of their travel. (and for upright pianos, repeats also require the keys to return nearly to the top) So, moving the sensor down may be an example of the DP manufacturers achieving a better overall compromise.

Now, for these rapid partial repetitions, yes, the dampers will not be touching the strings, and there will probably be more timbral changes for each strike, due to the fact that the hammers are striking strings that are already vibrating. As I've said before, a Clavinova I tested did seem to invoke a sustain-pedal like behaviour for slowly repeated partial notes, just as you say. (I realise we've discussed all this at length in the past) 2-sensor actions can't do this directly, although perhaps it would be possible to guess what the player is trying to do, and to invoke the damper-less repeats. ;^)

Greg.

If you give us a price point, it may be easier to help. If you can spend a lot, but have space and location restraints (neighbors), than I highly recommend the AvantGrand N1. After all, it has a real grand piano action. If touch is important, there is nothing better than the AvantGrands. Although, I'd rank Kawai's RM3 Wooden action to be superior to all other digital piano actions, and second to the AvantGrands in terms of action in a non-complete acoustic.

Have a look:

AvantGrand action
http://www.youtube.com/watch?v=bUsliF47RMU&feature=relmfu
http://media.photobucket.com/image/avantgrand%20action/virtualpiano/IMG_1703.jpg

Real Grand Piano action
http://www.fordpiano.com/wp-content/uploads/2010/07/action1.jpg


Interestingly dewster, the RM3 doesn't possess three sensors as far as I'm aware. RM3 stands for Real Mechanism, Real Motion and Real Materials. I may be wrong but I'm almost positive.