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Hey everyone -

I have a question!

How do you go about increasing the sustain on a piano. Is it just all in the soundboard and plate? How important are the hammers? (I'm not interested in digital options...)

Thanks!

Hold the key or the pedal down longer.

Less energy loss at bridge is the first option
a friend used to believe he aadded downbearing, by hardly tapping the wire in the bridge surface, because the wood harden under the wire the sustain increase (the bridge top is shot , after some time)

On the hammer side a lot can be said , the lowest partials are providing more energy, hence the impression of longer sustain when pre needling is done well (or re done at some point)

On the tuning side, if the coupling is well done within the whole spectra, between 3 strings that have most generally different pitched partials, the sustain is enghanced, while if we try to learn the note to tone all immediately, there is a sort of fight between partials that use too much energy.

Some pianos simply have more and better sustain. Although hammer exchange or voicing can make a difference on a good piano, the limitations are in what the acoustic body of the instrument will allow.

To remove the hammer as a factor you can pluck a string with a guitar pick. If the hammer produces a shorter sustain, then improvement is possible by working on the hammers. This could lead to a fairly costly hammer replacement.

If the hammer produced tone has the same sustain, then the soundboard/bridge/string assembly in its present state is not capable of more. Changing that is fairly invasive and also costly.

Are you not happy with your W. Hoffman piano? Was it made in Germany and how old is it now?

If you are still looking for a new piano, usually a lower-tension scale design can offer better sustain (see here).

Supply - you wrote



I am pretty happy with the tone of my Hoffmann. It's a T128 model, made in the Czech Republic I believe, although I'm not sure where all the parts are from. It's about 3 years old.

It's just I'm looking to upgrade to a grand for a number of reasons. I'm being confronted with the hard reality that I want a $60k piano, but I'm looking more in the $15-30K range, so I'm trying to get as good of an instrument as possible. Seemingly many of the lower cost grands are lacking in sustain, and I'm trying to find something I can afford that I'm going to be happy with.

Thanks for that info Bosendorff. That's helpful - I didn't know that.

Well if the hammers are left too hard to give the impression of tonal color, you may miss sustain.

The trick Jurgen gaves you is the best to choose a piano, hammers can be old or need some work, if you take the habit to pluck the strings and listen to the tone quality (not only sustain unless you mean thickness of tone) you will detect easily a piano that have a poor soundboard.

Try to make some comparaisons whenever you have the opportunity, and compare the tone of always the same note, for instance C64 on differnt instruments;

Listen how is the tone alimentation...

Wow - Thanks - I hadn't thought of plucking the strings to try to take the hammers out of the equation. Great idea! How do dealers feel about plucking the strings with a guitar pick, though?

And what kind of pick?? I guess a medium soft pick would be sort of neutral. Maybe a bass pick for the lower notes. I may be going a bit far on this one...

The hammer mass becomes ever more critical to sustain as you move up the compass. When the fundamental frequency of the notes nears 1K HZ-a relatively small reduction in the mass of almost all piano hammers will increase the sustain. It does this because the hammer string contact time in this portion of the piano compass is long enough that several fundamental vibrations occur before the hammer leaves the string. A lighter hammer here will damp the string less thus leaving more energy in the string.

Consult with a piano technician who understands this and has experience reducing hammer mass as part of the tone regulation process.

Thanks Ed. When you say "up the compass" I assume you mean - from the lower notes to the higher ones?

Wow, the anonymous author of that site comes up with some crass generalizations!
I think many real experts would dispute that a higher tension scale means or results in a shorter sustain. All or most concert grands have what you could consider a high tension scale. Is there anything inherently wrong with or short about the sustain of Steinway D? Ignore that "helpful information".

YMMV from one dealer to the next. Perhaps ask them to do it for you so you can stand back and listen. I specified a guitar pick because you never want to pluck a string with your bare finger, especially not in a showroom. You don't need to obsess about what kind of pick, or worry about plucking the bass strings - it is in the treble where sustain is an issue.

Would you please clarify the trade-offs here, Ed?

You appear to be saying that most pianos have hammers that are too heavy to maximise energy transfer to the string and sustain. Presumably there is a reason for this.

Withindale,
Well I can't speak for any specific manufacturer. But I will tell you that the first class I ever took on tone regulation was taught by Fred Drasche who was chief tone regulator at NY Steinway then. The first words out of his mouth were "the hammer has got to get away from the string",and "the voicer puts the tone in the hammer with the shape". I struggled with understanding that at the time. Then a couple of years later I was visiting my brother who was finishing his electrical engineering degree and he said "Ed, the inertia of the hammer has to be very significant to the tone of the piano".

I went on from there to eventually launch a systematic investigation into hammer mass/tone/touch issues. The simplest model is to think of the hammer as a kind of exciting "damper". An engineer would say "It is the mass of the hammer in proportion to the periodicity of the string that is most significant to the transfer of hammer momentum into string momentum".

Yes. 1K Hz is the second B flat above mid C.

Mass is one factor. Perhaps not the most significant. There are tradeoffs.

The energy imparted to the string is mass times the square of the velocity of the impact PLUS the square of the velocity of the rebound.

So, velocity is exponentially more significant than the mass.

Elasticity (springiness) affects the rebound velocity. Reducing mass for any given level of elasticity makes the hammer function as though it were less elastic. (picture a truck with heavy springs carrying a heavy load or a light load)

Light hammers (other things being equal) will result in a slower key return. (Only source for powering the key return is hammer mass plus maybe rep spring tension).

This is not to say make hammers light, heavy, elastic or otherwise -- just that these are factors. We tend to get in trouble when we absolutize one factor at the expense of others.

YEs I amalways a little reluctant with too much pushed generalisations.

The way the hammers are voiced, their style of pressing, the shanks sorting and adjusting, (the jead orientation and move in the vertical "horizontal" plane at moment of impact ,all that will also influence the way the energy is transferred.
(I forget the unison coupling, but you may be bored with that)

So from something I am basically agreeing with (no need to have too massive hammers to have a nice treble, light hammers produce an opened tone) generalisation may tend to give apelicular piano tone systematically.

We have her an expert voicer that consider all pianos may have "the French tone" he use all the hammer ressources, cut the power of FFF, and cut the base of the sghank so it is extremely flexible. that seem to provide a variety of tone colors at lower levels of playing but no possibility to play strong (and it is not reversible as you can imagine)

He may get that direction with extra light hammers, possibly.

greetings

Keith and Isaak,
The primary physics of the hammer/string contact time are most definitely a function of the hammer mass in relation to the frequency of the string. The non-linear elastic hammer felt/string contact time interactions have no impact on contact time.

Compare the elastic return rate of a string that you displace by pushing on it with your finger to the return of hammer felt from the same finger push-you can watch the felt spring back and you cannot remove your finger from any at pitch piano string as quickly as the T-modes move.

Force equals Mass times Acceleration to calculate impact speed does not tell you the resultant energy transfer into a taut piano string-you must have a factor for the speed of the string as well.

When shaping a hammer to reduce mass you shape on all the surfaces but the wearing one to reduce mass. This reduces the damping function which will increase sustain and brighten the tone. Many heavy, dense hammers will sound way too bright when you reduce the mass enough to improve sustain. For the OP-the need to have a tone regulator who can asses this important.

The "LightHammer Tone Regulation" protocols I developed some 30 years ago and continue to employ also include removing nearly all of the front key-leads. Repetition and ability to sense the speed imparted into the hammer at the key are evident in the greatest amount possible for a piano this way. I have done hundreds of pianos this way and the artists acceptance is well established. I have done tests where pianists choose from several pianos with varying hammer weights. Almost universally the performers choose the piano with the lightest hammers-even when the have been told by naysayers that what I do is radical!

The OP wants more sustain-lighter hammers is the only significant way to get that in the treble.

Wow - thanks for the input - this all seems very complicated...I'm too tired to try to digest this right now - this reminds me of high school physics class. F=MA. Maybe I should just get a piano that already has good sustain!!

The context of my question is that I'm piano shopping, and sometimes I find a piano that sounds ok, but doesn't have a great sustain. I'm wondering if it makes sense to try to increase the sustain on a piano like this, or just look for a different piano. This process of trying to find a piano I like for a decent price seems like it will continue forever....

Pianos do not have sustain. They may have slower or faster decay.

Most of what you are getting here are methods of making the piano louder. The louder you play, the longer you can hear the decay.

To slow the decay, what is necessary is to lessen the loss of sound energy. The only way you can do that is with changes in design.

However, it is possible that with proper excitation of the string (the way the hammer hits the string), there might be more components of the sound that retain their energy longer, or fewer components that drain the energy faster. This could be affected by adjusting the characteristics of the hammer.

But the only way that the lay person can slow the decay is by holding the key or using the pedal to hold the damper up. That delays the release of the tone, which is the end of the decay.