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Looking for recommendations on hammer sets for an early (1971) Kawai KG2C. A hammer set dark and mellow, then another set middle of the road, and then something harder and bright.

Looking for the same recommendations for a 1926 Bush & Lane, and also a 1925 Steinway M.

Comments and opinions please….

I have become more interested in voicing techniques, which influences what I look for in hammers, particularly after working with some Steinway hammers. I believe that there are two things that are important: the surface, and the inside of the hammers. The surface gives hammers the definition of the tone. Too soft, and it muffles the tone. Too hard, and the tone becomes thin. However, the surface should generally be harder than the inside.

I mentioned some time ago about bocce balls, the brass balls that my league plays with. Some of them are hollow, and will bounce when dropped on the court. Others, used by those who throw the balls through the air, are filled with weights like a dead-blow hammer and do not bounce. For a hammer, you want enough bounce that the hammer does not mute the string, but enough deadness that power is transferred to the string. The ideal would be that the hammer bounces off the string just about the same speed as the frequency of the string.

One of the things that means is that the inner area of the hammers should be considerably softer in the bass than in the treble. For Steinway hammers, that means that the treble hammers should be hardened, while for most others, that means that the bass hammers should be softened. The ideal hammer should come that way, possibly by having more heat in the treble when pressed while less in the bass. (That sounds like some sort of heat exchanger would work: pump hot liquid from the treble side and cold from the bass.)

I do not know if any hammers come like this right out of the box, but this is the way that I aim to voice them. Final adjustments, the ones that give them the mellow or bright tone, are done to the surface of the hammer, with shallow needling or a little bit of more or less viscous lacquer applied to the surface.

What I avoid are hammers which are so hard in the interior that little tone develops, and they are too hard to needle. Other than that, I can work with any.

BDB:

Thanks! There is too much "what to do" with hammers rather than "what hammers do" around here. You post was refreshing.

My recommendations would be (in order of brightness) Ronsen Bacon, Ronson Weickert, and Renner Blue Point. The Ronsen hammers typically play in quickly, so it is important to resist the urge to brighten them, except in the bass (where in my experience, they often need to be voiced up). The Blue Points are more of a needle down hammer, but still far from glass shattering. As to which would sound best on a KG2C, I'm not sure, but I've heard plenty of these pianos with really hard Abel hammers, and they sounded awful as a result.... I wouldn't want to use anything brighter than the Blue Points.

You might consider the Abel Natural Felt hammers. I've had good luck with them. They are very good right out of the box and after string fitting, etc., they sound even better.

Are these the ones offered through Pianotek? I've been curious about them, but haven't had the need to try them, yet.

Hey Beethoven,

Congrats on joining the PTG! Welcome aboard!

Both Pianotek and Brooks offer the Abel Naturals. They're not exactly the same thing, but they're very similar. Actually, there was a comparison of the two recently on the ptg website.

Regards,

I ordered these through Wally Brooks.

Thanks! I'm enjoying it quite a lot, already!

Inside of the hammer have to be dense in the basses (the zone under the strike . not soft.

the strike have also to be hard enough and to be supported by the sides and the underside.

The dynamic range is the main task of a hammer, while indeed the more the external core is resilient the more the spectra is rich at softer level of play.

There are now really good felts available there and the major brands make good use of those.

The felt may be very dense and it will give much when needled, but sometime the hardness is strange, then the felt have been made dense by pressing with heat (to obtain the wanted shore) it does not react well wen needled.
At the same time it needs a lot of needling (which disrupt the fiber) and the elasticity does not raise, the tone simply get less hard.

That is when having a bottom of the hammer with more density can help, unfortunately many hammers today have a soft base.

We have sometime hammers that will need not much needling then the original elasticity of the fiber is providing the tone much.

And some others have to be emptied totally , then need to be played for sometime for the tone to develop.

I could pre needle hammers prior to glue them, but I prefer to restrain doing so. For instance on a piano with old bass strings the bass hammers need little voicing, to keep more power and limit the high partials to sound too much (closed tone due to less needling)

In the end after having glued and needled a sufficient number of sets one begin to have a sufficient feel for it, and can feel under the needles what is going on in the fest and imagine what the tone will be afterthat.

Using needles from the name brand and thickness helps.

I had excellent hammers received from Förster, from Blûthner, Bösendorfer also have good felt.
Precedently they all where using some brand and felt quality, but those days they all pretend having a felt made to their desire. I would believe that they ask for a final pressing of the felt strips to their liking, as it would surprises me if they obtain really a special felt, but anything is possible.

Anyway the last WU superior quality is amazing and easy to work with. I rarely have seen a felt providing at the same time as much tone and large dynamic scale after a moderate preparation.

We begin to see the effects of the far better knowledge of hammer felt that is there since 10 years or so..

Thanks for all of the contributions. BDB your posting is indeed as Jeff astutely observes and much of the thinking that I have come to follow when looking for hammers sets for particular instruments.

I also take note of the hammer that was installed at factory and use that as a baseline for comparisons. Important too is what tonal quality the customer is seeking to have from the piano and make suggestions for their choices in accordance with my experiences of different sets.

Beethoven986,
Thanks for the suggestions on certain brands. I will research the sets you have mentioned for the Kawai, and probably communicate with Kawai about what was the standard fit for this model in the 70’s, what they recommend today, and use that information as my baseline to check out other quality sets. I believe that the majority of Asian pianos built today are high tension scales so I would lean away from the softer Ronson hammer sets for that one unless I was advised otherwise…..

Tom,
Thanks for posting, indeed the Abel Naturals are a hammer that slipped my mind and is one that I have intended on checking out. Thanks for the reminder.

Zeno,
Do you have any further comments you can offer about the differences of the two Abels from different suppliers, or perhaps a link to the thread over there?

Isaac,
Thanks for your comments. I agree the choices of premium hammers and hammer felt has improved greatly over the last decade. So many choices these days…….

I also do not voice hammer sets prior to installation and at times if the strings are also new I wait a while for the strings to settle in and season a bit to hear the piano and then make decisions about voicing.

The link to that discussion thread is: http://my.ptg.org/PTG/Communities/ViewDiscussions/ViewThread/?GroupId=1225&MID=230541

I'm not sure if that particular thread is public or not, but I believe it's open to non-members if you register for the website. Let me know if you can access it.

Thanks Zeno,

I will log in and read it over.

Dan, high tension scale, if from a point of view of the wire used (soft/hard) I understand, but on high tension scales the iH may be lower than on low tension.
What I mean is : if your raise the pitch, the iH lessens)

For some reason on low iH pianos softer hammers works better in my opinion.

For a KG Kaway, Renner hammers can be good, while "a little heavy"
They used to mount GR6 hammers on that KG2 serial when imported in France, that makes pianos with a more classical tone but downweight about 80 g in the basses. I have been told that the French importer was mounting those hammers himself (it may have be possible at that time, or he had an agreement to have those hammers used)
reference 519160613 ( long tails , GR6 ) Wurzen felt

RX have a DW of 60 g it may be only 20 gr more ! If you plan to have the best tone, you may wish to obtain hammers with "Weickert special" felt (seem to replace the WU AA quality which I cannot have anymore information on) delay 5 weeks +- (see holidays). Ronsen may use that felt today probably. I dont know if it is available on stock hammers, the models that are provided to the US market (which have the same thickness in basses and treble) I have seen the "Renner blue" that I liked , sound adapted to the voicing and wire used in the USA (if tyhis is Mape wire, carbon content is higher hence iH is also)

BTW I have seen comments from pianist testing a M& H in Paris : very surprised for the power underlying, but did not find comfortable the lesser tactile feedback due to the action.
Provide a somewhat heavy sensation while the touch is not really heavy in itself.

They also noticed that all the tone was at the attack moment, I was not dreaming of that difference in voice with European instruments.

Isaac, thanks for the additional comments and observations. I will do further research on that and probably order some samples of different hammer sets.

I had a couple of phone calls yesterday from local technicians here with similar comments about the softer hammers. PW member Jack H tells me he installed the Ronson Wurzen on a KG2 and the client was very happy with the results. I will have to check them out.

Isaac,

I checked out a couple of RX2’s I have in my tuning inventory here, and the touch is indeed heavy, around the 60g mark…one was over that in the bass. I have also heard from other technicians that the Renner can be heavy.

This is my experience as well.