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I am not a tech, but am looking at older pianos and considering restringing as part of the process. I often find pianos that I like the tone in one section, but find it to be inconsistent from bass to tenor to treble.

I play guitar, and I know adjusting the guage and type of string can have dramatic effects on the sound of an acoustic guitar. For example, if I put a larger diameter string, in general I will get a fuller, often warmer tone, more harmonics, and longer sustain, especially in the bass. It will also affect the action of the strings.....I will have to pluck harder to get a given volume, making the guiatar harder to play loud but easier to play softly.

Can the same thing be done with pianos? It seems that this would take some experience and skill, and perhaps even a computer to do computations. How can I be sure I chooose someone who knows how to alter sound to acheive a desired effect or just maintain the present sound of the piano?

What you are talking about is being done everyday by a number of rebuilders. It's called rescaling. String diameters and speaking lengths, wrap diameters, waste lengths, etc. etc. are entered into scaling programs or spreadsheets. Things like inharmonicity, loudness, impedence, breaking percentage, and a multitude of other factors are calculated for the orginal scale. Then a new scale is created balancing all the factors, and blending the registers as best possible.

Be aware that the string scale is only one factor. Inconsistencies as you describe are also related to soundboard design and health. Hammers and voicing also influence the outcome. And how well these factors marry to one another are part of the picture.

If you are buying a used piano, you would be advised to engage the services of a piano technician before you purchase.

Will Truitt

Inconsistency between registers is one of the many stupidities of over-stringing. Other than marketing (i.e., larger piano in a smaller case), I have yet to recognise any significant benefit of such a design. Mostly, it causes headaches and problems. Because of this change in bridge location in relation to the soundboard, you will always have a change in sound quality.

Pianos are already pretty much pushed to the max, in terms of tension and breaking points. If you wanted to explore the more colourful side and less projection, there are other options in terms of wire and overall scale tension used.

Just ask the rebuilder what they think they have the ability to control and what they think they can do. Usually, it is pretty common to take what is already there and refine it. If they have very specific objectives, however, you'll notice the difference.

I know of three flat-strung grands made in the past century. All of them are rare, and I have only seen one in person. I do not think it is a panacea.

The problem that many pianos have in the bass to tenor transition is that the tenor strings are severely foreshortened, resulting in very low tension on those strings. Raising the gauge helps, but eventually the stiffness of the wire is a problem.

Modern designers, like Del, are scaling pianos with more overwound strings, which is the best way to handle it.

The break between the overstrung and long bridge is the usual area that wire changes can bring improvement to a piano scale. Also the break between wound bi-chords and single wound string notes can be improved. The recent developments of Pure Sound stainless wire and Paulello soft annealed high-carbon steel wire offer many tools to improve the break area.

Much of the poor tone quality that we notice in these areas are the result of longitudinal modes. These new wire types carry less L-mode at a somewhat lower frequency than fully modern high-carbon wire.

These new wires also offer the ability to have more tri-chord and bi-chord strung unisons lower in the compass which helps make the tone more dynamic, warm and colorful. Having multiple string unisons is very important to true piano tone because of the mutual coupling between unison strings.

These new scaling principles are called "Hybrid Wire Scales". Not everyone who has recent scaling experience is adept at them yet. The protocols are in the process of being learned by many who have an interest in this skill.

Scaling the piano and the transitions with multiple types of wire gauged by breaking percentage furthers the rescaler's ability to "break the break", along with or instead of adding wound tenor strings. Stephen Paulello and Pure Sound make this kind of wire.

A well scaled piano can be designed or redesigned so as to make the transition between bass and tenor seamless on an overstrung piano. It takes skill,knowledge, and attention to detail to achieve this.

Most pianos are NOT pushed to the max in terms of tension and breaking points. Bad scaling can create problem areas where such conditions exist. Indeed, the low tenor section of most pianos would benefit tonally from wire at higher breaking percentages than is there originally. Using wire that has a lower breaking point will raise the breaking percentage (I hope that makes sense to you). You can change the wire type without the necessity of increasing the thickness of the wire. The tensions remain the same but the breaking percentage increases to a point that is more tonally palatable.

Some pianos will still require the use of wound strings in the tenor, nonetheless.

Will Truitt

The OP is thinking in terms of their experience with guitar. With instruments like that, one can go up or down with string tension to get different results. That experience doesn't directly apply to the piano. In those terms, the string tension on piano is already pretty maxed out--it doesn't mean the the entire scale design is already at maximum tension, but increasing the overall string tension, more than what it already is, isn't going to have the similar effect as the guitar.

BDB, I've seen/played/worked on hundreds straight strung pianos; they are not as rare as your experiences [in your part of the world]. A panacea has nothing to do with the statements that I made. Pianos were once built that way for a reason and then later changed for other/marketing reasons--which have nothing to do with the quality of musical sound. Sure, you can get a long piano in a shorter case, but who cares: just build the case bigger to properly suit the scale design in question. The extra cost to build a slightly longer piano is almost nothing. Want to guess the difference in production cost between a 5' and a 9' piano?!? Maybe for a 5' piano it is cool--where space is apparently a concern--but for a concert instrument, what, exactly, is the benefit of over-stringing?

A443, what EXACTLY are you saying that "the string tension on a piano is already pretty maxed out". That is not clear. What is your frame of reference?

One thing needs to be made clear here. In traditional scaling with one wire type, tension and breaking percentage go hand in hand - you can have any color you want as long as it is black. With hybrid scaling you can have up to 5 different wire types. You can have a string of a given speaking length, gauge, and pitch, for which you can quantify the tension, breaking percentage, inharmonicity, and other things. For each of the 5 wire types there is a different breaking percentage, yet the other values remain the same, while the piano improves tonally.

I think that we hear breaking percentage far more than we hear tension - scaling with the Paulello wire types has shown that to be true to me.

You can change the sound of a piano by raising or lowering the tension. Whether that is a wise choice or results in a more musical result is another matter.

Will

WOW, lots of info here. Much over my head. I'm gathering that it's risky to try to get a lot change in sound due to a string change.

My reason for asking is I'm typically finding 20 to 50 year old pianos that I love the tone of most of the piano, but the last 8-12 treble strings sound really thin and metallic with little harmonics or the the last 8 or 12 strings sound dead with less volume and a weak fundamental tone compared to the rest of the piano. On a guitar we may use a slightly larger gauge string for the unwound strings to remedy a thin or metallic sound or use a different type of string. Can the same effect be achieved, that is making a minor adjustment in string choice, to help a piano sound more consistent?

WilliamTruitt, the quote from the OP is my frame of reference, as stated above. Raising the overall tension on the piano, unlike the guitar, will not achieve the same results. Hence my comment that the overall string tension on piano is already pretty much maxed out, [comparatively speaking].

BillJZ, piano wire that is 20-50 years needs to be replaced. After about 7 years, it is already about time to change things up if the musical standards are high. The older the string, the more falseness creeps into the overall sound.

There are other strings that piano rebuilders can use (e.g., the Paulello wire as stated above), but these are not used in the same way that a guitarist thinks about string differences--modern day plain wire is steel, with different physical properties that apply to scaling issues that WilliamTruitt has alluded to.

BillJZ, most of the issues you seem to describe, don't sound like scaling issues, per se, but instead: hammer/voicing issues.

Are you talking just the plain wire or are you also including wound strings?



I think you're right, now that additional information has been added.

I am sure that in your travels around the world by horse and buggy, you have seen lots of flat-strung pianos. I said that I knew of three manufacturers who made grand pianos that way in the past 100 years. (Actually, two companies, since one of them made one model in one factory and another, different one in a second with different names.) None of them are in business any longer. I think that puts the onus on you to prove that flat-strung pianos are superior to what every manufacturer in the world has put their money on.

My generation uses airplanes to travel from city to city.

You failed to take note of my previous statement's details: over-stringing is done for marketing reasons, hence the reason manufacturers would put their money there. Since you interjected with your statement that the way pianos were originally constructed is not a panacea, then the onus is now on you to detail why you think over-stringing is somehow acoustically beneficial! Why do you think that is so? Can you describe ANY significant acoustical benefits for over-stringing? Perhaps some experience with the historical pianos and how they developed over time would help you put this issue into perspective.

I can recommend a few keyboard museums that you could travel to, but alas a horse and buggy will not get you there--you will have to leave the country and travel with airplanes. The upside: you'll know better next time around.

It seems to me that the discussion of flat strung pianos is essentially an academic discussion for others that distracts from the task at hand - BillJZ is looking for a used piano. The likelihood of him coming upon a flat strung piano that is less than 130 years old is slim to none. Don't get me wrong - I find them fascinating and would like to see the design revisited through modern eyes and knowledge, but the manufacturers are not biting.

BillJZ, the last octave, and especially the last half octave, is the most challenging part of any piano. It is a rare bird from any manufacturer to have much olume up there, much less any kind of sustain. I think most any piano out there new or used will disappoint you by way of comparison to your guitar.

It can be scaling issues most definitely. Strike point issues, voicing issues, regulation, hammer weight, etc......

Will

BillJZ, have you looked at newer pianos as benchmarks for comparison?

As an aside Stephen Paulello is marketing straight strung pianos.

If by academic, you mean to say that straight-strung pianos are only of theoretical interest, then perhaps you've entirely missed the point: by 'design,' an over-strung piano will always have an acoustic difference at the break.

While many of us can greatly improve the negative aspects of many manufacturer's scale designs and the transitions near the break, we can not overcome the design limitations of that system--we have to deal with it! If the break is off-putting to the OP, then that is worthy of noting now (i.e., it will get better, but a break will always be there by design)!!!

Whether or not manufacturers are biting is irrelevant. If no one talks about the issue, then there won't be any reason for companies to enact change. Competing salespeople would point to the change as a smaller piano in a bigger case; sales and marketing are not my concern: my objectives are increasing the overall quality and playability of the piano. Over-strung pianos don't serve that purpose.

In fact, there would be many advancements/improvements if we simply went straight back (e.g., there is no reason for the bass bridge to be that tall/massive/stiff, regulation and hammer alignment would be much easier and more precise, better tonal consistency between registers, etc.). There are many issues that could be discussed; limiting discussion is not a viable way to move forward through the muck.

Maybe. There was a date that has past, but no indication of whether they are available or not.

In any case, back to the original post, there are a variety of reasons why a piano would not be consistent from one part of the range to another. Some of them are due to the design. Some of them are part of the setup. Some of them are due to the condition of the piano. Some of them are due to the age of the strings, at least in older pianos. Unless you have enough experience to determine what is causing it, you cannot assume that one solution will be the correct one.

Perhaps, BDB, you should contact Stephen Paulello to find out what the advantages straight-strung piano designs might be--if there are any benefits to over-stringing, at all, that might be a good place for you to look for further information/experience/guidance.

I read what he said, which apparently you did not. Nor did you get the implication of his desire to make models both ways. I knew exactly what he was talking about. Do you?

Withandale, I've been aware for some time that Stephen Paulello is building a straight strung concert grand. I'm not aware that he has completed his prototype. I would love to see and hear it when it is done. Has he made it available yet?

Arno Patin is building a straight strung concert grand in his workshop in Livonia, Michigan. I know the plate has been cast, the rim has been bent. Not sure where he is at from there. He's the domestic source for Paulello wire. Arno's take on a modern straight strung grand is quite interesting, I have seen some of the drawings.

Del Fandrich has expressed the desire to build a smaller straight strung concert grand amongst his many projects.

A443, you should read more carefully before you start shooting from the hip. Nowhere did I say that straight strung pianos were only of theoretical or academic interest. I was trying to make the point that, since the likelihood that BillJZ would find a straight strung instrument youthful enough to consider for purchase was vanishingly small, in that context the discussion was academic.

My interest in straight strung pianos is there, and I would love to see them made. As for as large scale manufacture of these instruments, perhaps someone like Del can upset the applecart enough to shake things up. But I think even that is unlikely. You are tilting at windmills, A443. And I think you are overstating the problems at the bass tenor break. They are solvable and the break can be made invisible.

Will