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Hi, are there any full-size upright models (new, or reasonably able to find used) with medium-tension scale designs? Thanks.
They are all medium tension with respect to concert grands, which are high tension, and spinets, which are low tension.
Agreed with BDB. This one aspect alone does not make a great piano. Also the term doesn't have a literal definition, outside of a couple of marketing departments who use the term inconsistently, in the first place (and usually provide no data).
Thanks, so what's lowest tension force uprights can have, and the highest? Thanks.
No clue. It's not a published figure from just about every manufacturer. I just go by what the tone of the piano sounds like when I play it, and don't really care how we got there in the design phase of things. It either has a great touch and tone, or it doesn't. (sorry, not trying to be snarky)
I would suspect it probably mirrors the size - smaller instruments tend to be lower tension than larger ones.
Wire has to have a certain amount of tension to vibrate optimally. Anywhere from 50% to 70% of breaking point can considered optimal. Much more to it than this but that's a starting point for you.

Pwg
Originally Posted by Eric D.
Thanks, so what's lowest tension force uprights can have, and the highest? Thanks.


My feeling is that most people who refer to "low tension" or "high tension" scales really have no idea what they are talking about and are salespeople that are trained to talk about this. Every scale is relative and, although there are general assumptions we can make, there is a danger of expecting a type of performance based on a misunderstood and often misleading single data point.

My best advice is to play as many pianos as you can. Compare which you like, which you do not like, and which you could afford. Then come here and ask questions. We are always happy to help.

Cheers!
Not sure this is relevant, but I had a similar discussion once with Del Fandrich. We were discussing US made Baldwin upright pianos, which have a higher string tension scale than most. We were discussing the Baldwin model 6000 upright (52") in particular; but I've owned a Baldwin 243 studio upright, 45"/46"(?), (that I liked a lot) and you could see that the diameter of the plain wire strings was physically larger than other brands of upright pianos.

Del said that the higher tension string scale on the Baldwin uprights was one of the factors that gave it that unique Baldwin tone.

Beyond that, I don't much about string scaling on pianos, other than lower tension scale has smaller diameter strings, and higher tension scale has larger diameter strings.

Good luck!

Rick
1) I have never seen any of this information published at all.
2) If this was a factor that defines the performance of a piano, I believe, it will be pointed out on most websites and brochures.
3) If we had three different pianos all the same size: Piano A can have higher tension for the bass registers than Piano B and C, but Piano B and C can have higher tension in the tenor than piano A. How would you call these pianos high, medium, low.

I never heard about this at all.
Can someone educate me?
I think I am going to start screaming if I hear anyone exclaiming about Low, Medium, or High tension scales. If you ever did any engineering study of piano scales, and the parameters the strings are placed under, you would be left wondering what the heck they are talking about.
Thank you Ed,

It is good that you reconfirmed what I thought. This is a bunch of nonsense given by an ignorant dealer.
I didn't get it - why is this nonsense? It appears to me that this is an important parameter, and that this cannot easily be changed later on via voicing or regulation. If you look at the formula for the frequency of a string, the tension is as important as the mass.
A recommendation of better trust your ears and simply buy would you like in terms of how it sounds is of course good, but may limit you unnecessarily if the piano in question could be voiced more to your liking. But the string tension is not something that could be changed later on easily I guess.

Edit: Link to formula for string frequency:
http://hyperphysics.phy-astr.gsu.edu/hbase/Waves/string.html
First no one has defined what High, Medium or Low tension is. Is it absolute tension"? Or breaking point percent? And where in the compass is it High, Medium or Low?
Yes indeed, Ed, I have never heard this before. Thank you and Rich for setting us straight.
Sometimes on PW I learn something valuable that I can use again and again. Sometimes, threads like this make me more confused than ever.

Over the years I've heard piano rebuilders here talk about, (and even brag about) "rescaling" their rebuilt pianos to sound better than the factory original. I may be totally wrong here, but my uninformed and uneducated definition of scaling on a piano has to do with the size/diameter of the strings/piano music wire used from A0 to C88.

Also, I've been around other stringed instruments enough to know that there are different sizes of strings in terms of diameter. I also know that a larger diameter string will create more tension on the instrument (stringed instrument, piano, whatever). Hence, light gauge strings = low tension and heavy gauge strings = high tension. On a piano, I'm sure the heavier gauge wire will no doubt create more tension on the cast iron harp, more downbearing on the bridge and soundboard and more stress on the pin block.

Also, I hear the piano pros talk about how much torque is placed upon the piano due to the string tension. So, there has got to be a correlation between the scaling (size/diameter of the wire) the torque placed on the cast iron harp, and pin block, and will likely affect the tone of the piano. But, again, I'm no pro, and may be completely off base.

However, what I'm reading here (and perhaps between the lines or between the tension smile ) is that suddenly there is no such thing as tension, high, medium or low, and if there is, it doesn't matter or mean anything.

Here is a good explanation of piano scaling by Robert Estrin with Living Pianos. https://www.youtube.com/watch?v=uKoMOpc6TDQ ; I think he does a great job of explaining piano scaling, along with high and low tension scales, and what it all means.

Here is another explanation by Piano Tech Chris Vesty https://www.christhepianotuner.com/post-title ; but Robert Estrin gives the best explanation.

So, to say that simply asking about or discussing high, medium or low tension on a piano is ignorance or doesn't matter is a mystery to me...

Rick
Thanks Rickster but Estrin doesn't explain that you can place thicker wires at lower percent break strength by having shorter speaking lengths. Shorter speaking length scales have lower tension that longer ones, but if they have thicker wires it might be the same or higher tension than a longer scale.

Again, how do you define high or low tension. By diameter of wire or speaking length? They are two very different things.
From the Boston piano website:
"A rescaled bass and treble wire lower string tension provides increased sustain, better tone clarity, and a deeper, clearer bass. "

From the section on their 215 model:
In comparison to other pianos, the Boston has lower string tension. This reduced string tension, along with a tapered soundboard, creates longer sustain, and a more singing quality in the tone (as well as longer piano life).

The above raises the interesting question of whether Steinway pianos use a low tensions scale design and if not, why not.

I believe Boston pianos have always advertised that they use a low tension scale design.
Hi Pianoloverus,

In my opinion, this information is purely marketing hype. In my research about sustain, I narrowed it to how the soundboard system manages the energy reflections in the soundboard.
Among the literature I read was "Five lectures on The Acoustics of the Piano" The Physics of the Piano" there wasn't any information where they stipulated what defines a low, medium or high tension scale and never mentioned focusing on the scale tension as a primary factor for sustain or tone.
Even though most piano makers hype their products, it is strange that Steinway (an established name) offers vague information such as the one you described.
I like to think of string tension as comprising the specific tension, i.e., the force per cross-sectional area of the string, and total tension, being the specific tension times the string's cross-sectional area. The specific tension relates to the percent breaking force on the string, and for strings of the same density and modulus, is controlled only by the speaking length of the string.
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