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Are these pianos typically hard to tune around the bass break?
Tunelab inharmonicity readings always seem to make the curve on these models split-scale , tunelab 6:3 bass octaves in these pianos usually sounds wrong to me and i always need to adjust accordingly with aural tests. 8:4 is often closer to the mark.

Please publish your iH values from tunelab.

Thanks.

thanks for the reply, here are the values im getting


C1 0.541
F#1 0.334
C2 0.181
F#2 0.200
A#2 0.179
B2 0.088
C3 0.091
C4 0.352
C5 0.924
C6 2.922

Good numbers.

Let the pros comment further.

It may not be your bass octaves that are wrong, but more of the transition from 6:3 to whatever type you are using in the treble. When a spilt-scale tuning is needed the manual "strongly recommends" 6:3 in the bass. I believe 4:1 in the treble is the default, however I very rarely use it. After you take your samples and let Tunelab establish the tuning curve, if you will look at the deviation curve at the bottom of your turning curve screen you will see how Tunelab is going to transition from 6:3 to 4:1 or whatever you choose. Often with 4:1 in the treble, there seems to be a lot of deviation between the two. You can toggle through different octave types and find one that gives you less deviation. What you are looking for is to make that line as horizontal as possible and bring the two lines together in the middle. I will often use 2:1 or even 3:2 and sometimes even 4:2. Depending upon how much stretch you want in the treble.

On a side note, did you have a specific reason for measuring three notes in a row ? (A#2, B2, C3) Normally what I do is measure all the Cs & Fs up through the 6th octave, and then the two notes on each side of the break.. and in that order. As you probably know, the more recent versions of Tunelab will determine on its own whether or not a split-scale tuning is needed. On the vast majority of pianos I tune, they do.

Something else to consider, do you have the "auto-partial" selection turned on? With this feature on, Tunelab will listen and choose the loudest partial to tune with.

I've been using this method the past couple of years it has really seemed improve my tunings especially smoothing out the transition at the break.

Hope this helps! Keep in mind though that on some pianos the bass is going to sound bad no matter what you do. LOL

Thanks so much for that Ryan,

I'll have a play around with different octave types in the treble and see how that affects smoothness in the bass break region for me.
In that graph there is both a vertical yellow and blue line, what does the blue vertical line indicate ?


No particular reason for tuning 3 notes that i can remember, but its possible there may have been false beats on one of the notes so i took another reading for reference on an adjacent string.

I already have auto partial on from A0 to D#3 , its highest note setting.

Edit
I know that 6:3 in the bass is recommended for split scale but the manual also mentions that if you do decide to choose another interval, tunelab will optimize the interval together with the 6:3 octave depending on the note. Its in the very last paragraph of the manual.

I'm not sure why you have two lines. What version are you using? I have the iPhone app. I have one vertical line and it is black. It represents where the break is from wound bass string to plain treble.

Oh, I must have missed that last paragraph in the manual. I very seldom switch from 6:3 in the bass, but I do recall Robert Scott saying that he almost made 8:4 in the bass the default. The only time I don't use 6:3 is on a Steinway D that I service. But I say, try it. You can always retune if you don't like it.

Anybody who has the skills to make a unison in the covered strings already has the skills to make an octave.

Why not let the machine do what it does best, (the temperament and the treble), and let your ears do what they do best.

Instead of tuning to the machine and hearing whether you like it or not, try tuning directly to where you do like it to start with. It is a good idea to keep the machine on so that you don't risk breaking strings by going too far away from its dictates but tune your octave as close to still as you would tune an unison.

Check the fifth and it's compounds, they should be tempered but not obviously so and the thirds and their compounds which also should be tempered but again, in the bass, not obviously so.

Try to get the Major tenths as slow as possible while keeping a not too obviously tempered fifth in keeping with as clean sounding an octave that you like. If your taste runs to heavily beating faster intervals that's OK but be aware that they tend to draw attention to themselves.

You will find that an infinitesimal movement that is almost unnoticeable when you come to put in the unison will change the balance between the thirds, fifths and octaves quite a lot. Even an unnoticeable change in the unison itself can clean things up. The trick is to maintain this balance all the way to the lowest note.

This will work well on a U3. Smaller pianos may demand more compromise. It is OK to start the ear tuning from higher up in the temperament if it's not working out, A3, for instance.

Go on, amaze yourself. You have already discovered that the machine is next to futile in this register.

My experience with the U3 is that it is one of the least likely pianos to have progression problems about the break, IF you follow the wise advice of rXd above.

I can't understand the reasoning behind tuning to a device first and then listening to decide if it sounds right. If you are able to make judgments by listening to octaves for example, why not tune first to your judgement and then maybe use the device to verify. Or better still, use progression tests to verify.

Edit: If you do as rXd says, all the theory about iH inconsistencies and octave types becomes academic. The piano will tell you what to do.

Great suggestions to try out, Thanks Amanda
I do sometimes struggle with hearing certain partials in the low bass as often there is so much noise with conflicting partials with some much louder than others. This gets even harder with false beats/bad strings and hard hammers.
Certainly it would be less stressful if a device can do a lot of the work for you, however i do acknowledge that ETD's are only a tool and they don't always make the best choices.

Thank you.

When hammers are hard and the tone is harsh with a confusion of partials is where the use of intervals other than the octave really becomes essential for me, both as a guide to optimum least worse position of the octave and a general least worst sound over the whole piano. Even in the largest instruments that are so harsh. .

In such a confusion of partials, making a perfect match between any two if them usually makes matters worse. It is when pianos are so "rich in harmonics" that the fundamental is weakened that differences in winding come to light, often exposing rogue partials and other sounds that can't be reconciled without everything else being and sounding very wrong. This, too is where other intervals keep us in line.