Unique sound from Prellzungenmechanik

Key

During the investigation of the history of our very old piano made by Franz Oeser from Vienna, we dove in the mechanics (action) of the piano and found that it is partly responsible for the typical sound. We didn't know this when we decided to create a virtual instrument out of the piano. But apparently this is part of why people are triggered by the unique sound it makes.

The action is a Prellzungenmechanik, more widely known as the Viennese action, as developed by Stein-Streicher in 1780. It has an individual escapement mechanism and a check. This action was appraised by Beethoven and Mozart and many others because of the brighter and distinctive tone (still very warm to our modern taste) their action generated. This was especially preferred by musicians of the classical tradition as well as for chamber music, because they blend exceptionally well with stringed instruments.
Mozart owned a Stein piano from the father of Nannette Streicher - Stein, Johann Andreas Stein. Beethoven's most important of the early Sonatas is the Pathétique, which demanded a wider piano, stronger frame and more resilient strings. Nannette Streicher - Stein made pianos to accommodate Beethoven's needs.

Looking into the history of the piano and its mechanics is super educational. And luckily the digitalization of many old documents help us to search for many interesting details regarding such old developments.
For reference I've added the schematic drawing of the Stein-Streicher mechanik from 1780, which is the same action as our piano.

David Crombie even wrote an article on World Piano News on this subject: https://www.worldpianonews.com/general/explainers/early-piano-actions-and-the-oeser/

HZPiano

Key super educational

Highly interesting indeed, thanks for posting!

Cheers and happy digging,

CyberGene

Relatives of mine own a very old Bösendorfer grand that they offered to me if I want it. It has the same Viennese action. I’ve read these actions are not very good, so for the moment I’m passing on it (and it’s stored vertically, so I can’t test it). But I’ve watched a lot of videos about these actions and how they are regulated. The good news is they are much simpler than modern actions, so there’s not a lot to regulate. They don’t allow for repetition without fully releasing the keys but I’ve heard the action itself is very light and quick, so it partially compensates for that.

Key

CyberGene Yes, this is a very simple action and the playability is light. Somehow this type of mechanics contributes to a certain tone of the piano. We found that in our studio people kept playing this old, most often out of tune, piano in our lounge. And they all loved the sound of the piano, which inspired them to keep on playing (most often during the recording/lunch breaks). I don't think this action could be described as very good, but it's not bad either. It just is capable of contributing to a more unique sound of pianos of that time.

dore_m

So correct me if I'm wrong - a piano action definitely is what connects the player to the instrument, but the actual sound that the action affects is due to the speed of the hammer and the qualities of the felt of the hammers. The particular action (aside from the hammers) would increase/decrease the dynamic range of the piano according to how well the user can control the speed of the hammer strike. I'd think that an older action would produce a smaller dynamic range than a modern action.

Were the hammer felts on the Oeser different from modern hammer felt (Abel or Renners?), were they prepared differently (harder or softer?), or are they just worn - giving an older but possibly purposely uneven character?

CyberGene

The Viennese action may affect the sound. That has been commented on PW. Because the hammer is pivoted on the key instead of being independently pivoted on a static rail. Due to this, since you are moving the key while the hammer is touching the string, and because of the geometry, it’s possible for the hammer to also slide slightly along the string, rather than just hit it in a single point. Theoretically that would affect the sound.

dore_m

CyberGene since you are moving the key while the hammer is touching the string, and because of the geometry, it’s possible for the hammer to also slide slightly along the string, rather than just hit it in a single point.

Here's a video that shows it in slow motion. Not sure that I buy that the hammer "sliding" has an effect, but I admit it's possible. I'd think that the felt would then have a much larger effect - I mean softer felt would be grippier on the sliding motion.

https://youtu.be/NeUL3qYJQuo

Del Vento

Ralphiano It is interesting to see how much the hammer shank bows

Ralphiano depending upon where exactly in this oscillating cycle the hammer shank was at the moment of hammer-string contact.

FWIW there are videos of modern actions that show similar a thing.

dore_m I'd think that the felt would then have a much larger effect

I agree with you. The whole point of voicing is based on subtle modification of the felt which cause massive change in tone (look at the PW technician section where there is always discussion about that, especially from Rich Galassini).
Also, the mass of the hammer play a large role.

HZPiano

dore_m video that shows it in slow motion

That is nice, dore_m , thank you!

Cheers and happy flexing,

Ralphiano

It is interesting to see how much the hammer shank bows the moment the toe and jack come together, but before the felt hammer head starts to rise. On the way up, the hammer shank would be oscillating back and forth until that energy would be dissipated. I suppose that had consequences for the player, as different speeds would result in the hammer striking the strings at a range of angles, depending upon where exactly in this oscillating cycle the hammer shank was at the moment of hammer-string contact.

Key

@CyberGene You are right on the motion of the Viennese action. So, it's not just dynamic control the action is responsible for, but in this case also partly the timbre.
Voicing is absolutely very effective in changing the tone. If not more effective.
It's just that, in our case, the action is partly responsible too. And upon finding that out, we thought it would be nice to share.
To quote Alfred Dolge, who wrote "Pianos And Their Makers" in 1911:

'Meantime, Johann Andreas Stein, and his talented daughter, Nannette Stein-Streicher, who was not only an excellent musician, but also a thoroughly practical and scientific piano maker, had improved the Schroter action so materially that the grand pianos made by them from 1780 on, were preferred by Mozart, Beethoven and other masters, perhaps mainly for the reason that this action not only had a more elastic touch than the Christofori English action, but that it produced a more sympathetic tone, reminding of the clavichord tone, which all the great players of that period admired so much. This sympathetic tone could only be produced with the Vienna action, because the hammer, when striking, would to some extent graze or draw along the string, while the more forceful attack of the English "jack" action is a straight and direct percussion. These two elements, the pleasant light elastic touch, and the charming musical quality of tone, assured the Vienna grand pianos (flügel) supremacy in Germany, Austria and Italy for many years.'