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Plus it doesn't sound like he thinks you are wacko! This could be his greatest asset considering that what you are after is a little out of the ordinary. There are a whole lot of folks out there in the piano world who are either frightened of, or antagonistic toward, anything other than the (modern) traditional norm.

Please keep us informed.

ddf

very good,

please post some more audio

have you considered adding more leather in the bass section? it was normal to do so on fortepianos.

you will have to re-adjust letoff again, but it's a simple procedure

Hi again

I have put some more recordings here, have just come home from work and usually I'm more musical in the morning ...
However, I felt like doing some recording:

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http://bildung.freepage.de/pinboard/piano/

beethoven_sontata_pathetique_first_movement_(only first part).wma

beethoven_sonata_pathetique_2nd_movement.wma

mozart_fantasie_c.wma

bach_wtc_1_prelude_20.wma

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Description of my latest "configuration" with reducing the blow distance a bit further. The above recordings are 'at full stick' (fully open grand piano) with this regulation, the microphone being at about 2m distance from the piano and on the level of the strings.
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I have tested layers of felt under the leather for the hammers, but nothing was as good as the three (or sometimes four) layers of chamois leather.

Only the tip of the hammerhead is waxed when the leather is already glued on the hammer core. Rub a white candle four to eight times up and down on each hammer tip and spread the wax evenly with your fingers. Too much wax ruins the voicing and makes the piano sound too hard and metallic. Rub the wax on every hammer. If you apply to much wax, you will have to replace the top leather. No wax makes the piano sound less articulate.

10 Regulating the action

Put the action rail into the grand piano, then pull it out half-way so that the hammers are in a line under the wrest plank. Watch out that the action rail does not fall out. The treble hammers may have to be more in when the bass hammers are regulated. Use a knitting needle of 1.5 mm diameter to screw out the capstans in the bass. The hammers should tighlty fit under the wrestplank, when the action is pulled out or pushed in. Leave about 0.5 mm room for them to move. The capstans of the treble hammers are screwed out so that they have 5 mm room to move under the wrestplank. Get a wooden batten (e.g. fir tree) which is 5 mm thick to help you measure the space beween hammers and wrestplank, when adjusting the capstans of the treble hammers.
Last, adjust the let-off. In a Yamaha grand piano, the let-off buttons are screwed on a wooden batten, one batten per section. This batten can be slightly unscrewed from the action rail, raised and screwed on tight again, if a new type of hammer is installed in the piano. After that, the separate let-off buttons can be adjusted with the knitting needle to set the let-off point (Auslösungspunkt in German) correctly at 1 mm distance from the strings.
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I did not put more layers of leather on the hammers in the bass for the following reason: I want the bass to stay as slim as possible. The bass is still very powerful, as you may hear on the recordings. However whith the light weight hammers, the bass remains more 'transparent', 'wiry', which is more suitable for the 18th and 19th century piano music than the bass we get on the modern piano.

Today I removed the 6mm thick plywood board I had added below the soundboard, closing off the under part of the piano to reduce the volume. The bass was stronger and even the treble a bit stronger, but I did not like the thumping noise from underneath the piano. So after some minutes, I closed the soundboard off again from below.

I realized that this plywood board was contributing a lot to the sound I like most. It also helps much in keeping the bass transparent and rather 'wiry'.

The plywood board is fastened to the rafters under the piano by driving in several screws in a row at both ends of the board. The screws are driven through two battens glued on to the board. The batens function as brackets, which press against the rafters of the piano when the screws are driven in. The screws are pressing against another moveable batten to protect the rafters from the screws, about like this: \\________// . Screws are driven through the moveable battens exactly at the points where the pressing screws attack, to protect the moveable battens themselves from being drilled through. This way, no marks are left on the piano. The plywood board is held in place only by pressure.

The sound can be a bit harsh at times, so from time to time I use the una corda (left) pedal to get a softer sound. Especially when I have played for a day on my digital piano only, I need some time adjusting to the different sound of my acoustic grand piano. Sometimes I play with the lid closed for a while. Usually after a few minutes, I open the lid of the piano.

Waxing the top layer of leather is not an ideal vocing procedure. I added a fourth layer of leather which I washed shortly with warm water before cutting and glueing. This makes the top layer harder and stronger. Of course, the leather has to dry after washing.

This is important especially for the top layer. I suggest using four layers of pre-washed, about 1.5 mm thick Chamois leather. Add an additional layer, if the sound of one note is too harsh. I would go a bit on the softer side of tone. After adding the top layer, play the piano for at least a week before hardening the top layer with starch paste water as a voicing procedure, if necessary. Playing the hammers will harden them too. To apply the starch paste water, use a brush or one finger. Protect keys and action before by inserting cardboard between the action and the hammers. Make sure the hammers are perfectly dry before inserting the action back in and playing the piano to test the sound. The procedure may be repeated serveral times. I did not test the voicing with starch paste water, however it makes sense, because the soft leather behaves very much like textiles. Starch is least aggressive and can be diluted by degrees with water. It is a totally natural substance.

The problem with several relatively loose layers of chamois leather is that the sound in the piano range is somehow muffled. Only in the forte range the sound is fully developed. I am talking about timbre, not only volume. With only two or three layers of chamois, the sound gets quite harsh after having played for a week, which compressed the chamois. One may easily slip unintentially into a harsh forte.

Rubber, on the other hand, cannot be compressed in the same way as chamois, however the rubber surface leads to an unappealing, metallic sound, which is too harsh. I am experimenting with just one layer of rubber band (http://en.wikipedia.org/wiki/Rubber_band) and one layer of rather thick chamois leather, washed and dried before cutting. While the rubber has a consistent texture, the chamois has a nice surface which gives a note a nicer tone. The idea of combining both forces came to me just this morgning when I woke up. I have to go through more tests ...

The most difficult region in terms of voicing is the range from note 23 to 47 -- one and a half octaves below the middle C and half an octave above it. Below and above that range the voicing is usually fine with two to four layers of chamois.

funny you should mention the plywood, because old viennese pianos had a slab of wood underneath.. the case was sealed.

as far as the sound of the chamois, I would have left it soft, and perhaps pulled it a bit if it's too dull and thumpy.

water on leather is not a good idea IMO

as I mentioned before there should be more leather on the bass

Found this totally absorbing thread only today - OZ time. Sorry for jumping back on the posts, but the early restorations of fortepianos, bear little resemblance to the later ones. Ditto for square pianos that can, if properly worked on, have a really sweet, sustaining tone. (Apologies to Larry Fine for his comments re Squares!)

Being a huge fan of fortepianos I am waiting eagerly to see how this **really** valuable thread develops.

All the very best from Warrandyte, Oz!

My situation and approach can be summed up as follows:

- I bought the smallest Yamaha grand piano second-hand, because the price-performance ratio seemd OK.
- I liked the transition from treble to bass (on most Yamahas C1, C2, C3 I did not like it, too much like church-bells)
- At my home, the piano was far too booming (loud)
- After experimenting with reducing the blow distance I realised that this did not solve my problem. It just made playing the piano feel awkward. Only smaller and lighter hammers would really change the sound of the piano while at the same time letting almost intact the 'normal feel' of the action when playing.
- The leads in the bass keys had to go completely.
- I basically wanted to use the same hammer for every range of the piano. First, this makes things easier and second, it reduces the booming in the bass.
- I finally used one layer of rubber (cut rubber bands) and one layer of chamois, about 1.2 mm thick, with only the chamois being glued to the hammer head, and the chamois leather holding the rubber in place. The rubber is slightly bulging. The hammer behaves similarly to a badminton shuttle, both dynamic and braking the violence of the hammer blow on the string.
- The rubber itself would not create a nice sound, it needs the surface of the leather to be 'rounded off'.
- This is not a historical fortepiano, of course, and my aim was to tune down the violent bass. Therefore, there is no sense in using real historical hammers for fortepianos. I had to come up with a different design.
- I really wanted the look, feel and stability (tuning!) and the action of a modern grand piano. At the same time, I wanted a much lower volume, but still an articulate, clear sound, something akin to the fortepiano.
- The brilliance of a concert Steinway or Yamaha was never my goal, neither was a completely voiced down muffled sound.
- I wanted to keep everything as simple and low-cost as possible. I think I have reached my goal of getting a real modern grand piano with a beautiful and interesting tone that speaks to me.
- I have to continue playing the piano. The hammers should be completely stable after about two weeks of playing. The leather will have been compressed maximally, the rubber will not be compressed. If this type of hammer holds for three to five years of playing, before I have to replace the layers of rubber and leather, I consider this a success story.
The fitting took me about 10 hours of work, which is an acceptable bit of work say every 5 years.
- The spruce hammer heads should not have to be replaced. They most probably will not be damaged or worn down. They were varnished with glue to protect the surface.

Thanks for the update. I appreciate your efforts to experiment and to report your results.

ddf

Here some more pictures:

http://bildung.freepage.de/pinboard/piano/

The rubber-and-chamois-coated hammerhead:

DrawingRubberAndChamoisCoatedHammerhead.jpg
RubberAndChamoisCoatedHammerheads1.jpg
RubberAndChamoisCoatedHammerheads2.jpg

The piece of rubber-band is about 3cm long. The lower part of it is dipped in glue, and so is about 1 cm of the chamois strip below. When gluing the chamois to the spruce hammerhead, the tip with the rubber-band is fixed with a clothespin, then the glue is put on the chamois leather and the chamois is then strung with a 40cm piece of string until the glue has set. I used some universal waterproof white glue.

The lower lid:

LowerLid1.jpg
LowerLid2.jpg

Tonight, I could increase the blow distance to something more close to the standard, to say about 4 cm. Even an increase of half a centimeter blow distance has great impact with this hammer design. The action is clearly rather designed for this blow distance. Accordingly, the feel in my fingers is much better than with a smaller blow distance.

I haven't been regulating more than the capstans, the let-off buttons and the drop screw, either.

The rubber coat acts like a shock absorber. The dynamics could be improved even more, both the piano and the forte ranges are now quite attractive. The volume is thinning out in the top ranges, very much like on a fortepiano. The bass is quite strong due to the long strings, which have much energy, but not overwhelmingly so. I am very pleased with it.

I have to wait till the next day to play more, because the house rules prohibit playing after 10 p.m. ...

Hammers and sound are stable. I like the piano very much.
The sound has something rough and delicate at the same time. It reminds me of a human being, talking! It is very expressive. Unlike with a Steinway, the 'singing' does not come from the basic sound itself. This instrument has to be played muscially to get the sound singing. Mozart would have loved this, if he was stuck in this century. The singing of a Steinway can get in the way sometimes, especially if the singing is at a barking volume. But let's not generalize. What matters very much is the size of the room. My room is small.

The action is very responsive and subtle. The keys are really light in comparison to the standard Yamaha. It needs some getting used to, to reach its full potential, but once you're there, you would not like to miss it.

I have done some more research on the leather. As I understand, I put on a layer of sheep chamois over a layer of rubber. There is also deer chamois, slightly thicker (1.8 to 2 mm) and more consistent in texture, but also quite soft. I can get it from a different tannery some 50km from here. They import it from Austria, they said.
I will try this deer chamois out, when the current layer of sheep chamois is worn. So I'm not in a hurry while everything is still in good shape.

People are always asking for sound samples. I put some recordings on with my bad playing with the old configuration of the hammers (3 layers of chamois). The thing is that even with the best recording, you lose much of the real thing. It's best for a piano lover or technician to try this configuration out for themselves. A recording is only a bad picture.

The music stand on the smallest of Yamaha grands cannot be adjusted by sliding it in or out. It is fitted like on a Viennese piano or a Broadwood very much in front. In this way it shields the lovely direct sound from the hammers from my ears, which is not ideal. So I glued some 3mm red felt under the music stand. When playing, I open the lid at full stick and place the music stand on the cast iron frame, so I get the direct sound from the hammers in the mid-range.

It is the most amazing thing for me, to be able to play for hours without ever feeling the sound to be too much for my ears.

next time you re-do the hammers you might want to round the tip of the hammer-core.

You are absoutely right! I already got tired of the rubber and sheep chamois hammer tips. After a while, the sound was not articulate enough.

I have tested the deer chamois from Austria, which is about 2mm thick, and superior to the sheep chamois. It is more resilient, more consistent, while still being rather smooth. My tests on the piano, with the same hammer in all ranges, were quite encouraging. And this only with one layer of deer chamois leather on top of a fir and beechwood core. The sound is improving more and more!

One problem was that the leather would be very strained at the edges, when I used only leather and not the bulging piece of rubber. A rounded surface is much more stable for leather.

First, the Viennese fortepianos had hardwood hammers with no leather at all, until the 1780s, when leather tips were introduced. The earlier fortepianos only had one or two layers of leather (1810s), but the hammer underneath was rounded and looked a bit like the tip of a mushroom:

http://hammerfluegel.net/viewer.php?albid=67&stage=3&imgid=958

I will glue two crescent shaped wedges of wood at both sides, at the tip of the hammerhead. With the hammerhead, the diameter of the circle top will be 12mm. I will fit the deer chamois on top of this 'mushroom tip'. I will test if stringing the leather on the hammer tip with nylon will be enough. It takes me too many hours, cleaning the glue and leather away, when I want to replace the top leather. I think, the leather will hold much better, because of this 'mushroom tip', even without any glue.

It will look something like this:

(|)
.|

I ordered crescent shaped battens from a joiner in my area of town, and I should get them this week. I will cut the 11mm wide pieces from it myself, either with a saw or with a kitchen knife.

In the future, replacing one layer of leather will take me about three hours instead of ten.

Today, I got the battens in crescent profile from the joiner. He lent me a miter-box saw (Gehrungssäge), with the locking latch missing, but it could easily be fixed using a dowel.

I ordered both beechwood and firtree battens, but finally decided on the beechwood. Anyway, the difference in weight is next to nothing given the small mass of the pieces.

I fixed some metal and wood with vises (Schraubzwingen) to have exactly 11mm for the sawing width of the pieces. I fixed the miter-box saw to my kitchen table with vises (Schraubzwingen). After a few minutes I got the knack of it. I checked the sound again with one hammer, it seemd quite OK, very articulate this time. Tomorrow I will give the wood piceces a soft finish with sandpaper, then glue the pieces to to hammer tips.

The leather arrived by post. I will cut it in stripes during the next days ...

this is interesting.

I still think you need to put more leather on the bass, though.

the mass of the hammer core also counts, which is why hammers below the treble had these rounded parts you want to glue in.

every hammer is essentially a mallet.

some mallets are built small, some big, some have elastic sticks, others have thick metal sticks...every single element from the hammer-shank to the wood to the outer coverings has an influence.

drummers spend a long time choosing their sticks, which compared to piano hammer are quite identical, apart from size.

so..

The sound with my new rounded hammers was still too loud, above all in the third octave in the higher treble it slipped very easily into a shrill note.

I had to experiment a lot with different configurations of hammers. Looking for a low-volume, nice, articualte, crisp AND still muscial sound out of a modern grand piano with about 70 kg tension on each string (!), I was having a hard time.

The only solutions I could think of was: Reduce the weight of the hammer even more, because I didn't want to lose the crips sound, which was due to the beech wood with only one layer of leather.

Effective solutions are simple and elegant. Now this here is my grand piano hammer version 6.0:

- Same hammer for every section. I insist on that. It does for the bass exactly what I want: lean, crisp, clear sound, while still full. Making the most of a short baby grand piano, way better thant bigger hammers. I have tested it several times.

- Hammer shank extensions from aluminium knitting needles, 2 mm diameter, inserted into the original maple hammer shank with the original knuckles etc.

- Hammer cores from beech wood, round batten, 1 cm in diameter, cut in 11 mm wide pieces. The aluminium knitting needle is inserted through a hole at the bottom of the hammer core.

I plan on not glueing, but wedging the knitting needle in the holes with nylon thread. Glue would be permanent. I want to be able to replace old cores in the future for repair work.

- The hammer cores are coverd with one layer of chamois deer leather, glued to the core at the ends.

- No backcheck tail is necessary on this hammer, because of its small weight. Saves even more material on the hammer.
(Remember that I have removed the leads in the piano keys!)

- The dynamics of this hammer is amazing. From a mere whisper to a real fortissimo everything is possible. Clear crisp sound, something between a modern piano and a fortepiano.

- Repetition is excellent. Regulation is quite easy, this system is very tolerant on regulation. Set let-off and drop and you're set.

- The hammer shanks can be adapted and regulated to every angle in each section simply by bending them.

Here are some pictures of the hammer:

http://bildung.freepage.de/pinboard/piano/AluminiumHammerShank01.jpg
http://bildung.freepage.de/pinboard/piano/AluminiumHammerShank02.jpg
http://bildung.freepage.de/pinboard/piano/AluminiumHammerShank03.jpg
http://bildung.freepage.de/pinboard/piano/AluminiumHammerShank04.jpg

I have to make all the hammers yet, using the old shafts with the knuckles. It has taken me quite some time and effort to come up with this really simple but efficient design ...

I corrected the diameter of the knitting needle hammer shank to 2.5 mm. 2 mm is not stable enough, 2.5 mm aluminium is less wobbly. The knitting needle has to be bent without heating or it gets soft at the bend.

The ends of the knitting needles are filed to get a clean, plain cut. The hammer cores (the beechwood cylinders) are glued to the knitting needles. The glued part is quite resistent, but with plenty of force applied by turnig the beechwood cylinder round, the glue is broken and the hammer core can be detached for replacement.

The butt of the original hammer shank is drilled to stick in the aluminium shank extension. I have varnished the insided of the drilled hole with glue. The aluminium shank extension is not glued but only wedged into the the glue-varnished hole of the butt. The idea is to recylcle the parts of this hammer if they need to be replaced.

I'm still waiting for the rest of the knitting needles. In the meantime, I'm glueing the deer chamois leather on the beechwood cylinders. After some more tests, I have decided to use two layers of leather instead of only one and I turn the outside of the skin outside so it hits the strings. The sound is promising.

I have compared the sound of the new hammers against the original hammers. The piano was clearly designed for the original hammers. The sound has this rich and resonant character of the modern grand piano. However the hammer is too heavy and the sound too loud. My new hammer holds back the sound quite a bit, but the sound is still articulate and interesting. And it is not loud at all. Repetition is excellent and I can go from merely brushing against the strings to really hitting them, ppp to ff, relatively speaking. However, the ff is not much in common with the ff on the modern piano.

Picutres are here:
http://bildung.freepage.de/pinboard/piano

Hi Puck01,

with your aluminium hammer arrangement, do you find that the strike point on the strings changes as you play louder? I'm thinking specifically in the high treble where the strike point is quite critical due to their short length - In my mind I can imagine the hammer shank flexing backwards as you play louder, increasing the distance between the hammer head and hammer shank axle.

I'd really love to hear some sound samples but I have not been able to download any of your previous links (pics yes but recordings no). Could you upload a vid on youtube?

Good luck with your project!
J

This has been a difficult time. After a few days my ears adapted to the piano sound. It was less loud but still harsh and nasal into the bargain. Even with this smallest possible hammer. The strings and soundboard are clearly not designed for such a type of hammer. It sounded like the caricature of a piano.

I will not touch the strings because that is yet another adventure into the unknown.

It was an experiment. I was enthousiastic, obsessed even, but I am not anymore. This used up a lot of my energy.

It's a pity I haven't found my ideal piano.