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Hi all

On recently completing a tuning on a small spinet, i used beatless octaves from the temperament up to high treble. I was testing triads up and down in differant keys and found some high notes seemed 'dull' as if they were slightly flat. they were all tuned beatless and I assumed this would include the required stretch. I tuned some high treble notes slightly wide of beatless and they sounded much more 'brillent/sparkle' when played up and down the keys, It just sounded much better to my ears as a piano player. Is there a scientific reason for this? Maybe pianos such as this with high harmonicity need extra stretching than what is already built in?

Thanks again,
Jim

Greetings,
There is nothing "built in". We have to put it there. If you tempered a perfect 1:2 octave, and then moved out by pure octaves, you would have a lack of congruence between fundamentals and partials.

When you say you tuned beatless octaves, I must ask, what kind, double, single, triple? Can't have them all beatless at once, so which one are you referring to as beatless? . If single octaves are tuned beatless ,all the way up, the fundmentals will be flat of the partials from lower notes that are matched and the piano will usually be considered "lifeless" by those with some objectivity in their ears.
Regards,

I tuned a spinet the other day for the first time in 30 years. I tuned what i wpuld call a lot of stretch into it and still the treble sounded flat compared with what I am used to hearing and I normally don't stretch much at all on full size instruments.

One of the things that took me into tuning was the problem of small instruments in a collaborative rôle with other instrumentalists. I have always found smaller instruments inadequate for this purpose. I am currently advising on instrument purchase and have specified nothing less than 7' for instruments being seriously used with other instrumentalists who will be judging pitch from it.

Just to add that yesterday, I had a nap at my girlfriends pied a terre in town while she was playing the piano two closed doors away and two floors down. The treble sounded narrow as I could only hear the bare bones of the tone quality. I had only tuned the instrument 10 days before. When I went downstairs again, I had her play the same thing and it sounded perfectly in tune with the added depth and lustre of tone and presence.

I just add this asking could it be the thin, low quality sound along with the usual other factors that wants us to hear sharper trebles and flatter basses in these smaller instruments?

When I say I tune with minimum stretch, this is in keeping with policy of the handful of tuners that look after the major concert and recording venue's in London that I am a prt of. None of the sophisticated audiences or artists or hard bitten experienced studio and symphony musicians or producers or listeners all over the world (we do all the BBC stuff) ever complain of the tuning and some of my colleagues tune less stretched than I do in some predictable spots. This has been policy on all parts of the world that I have done this type of work. Who are the people that want to hear high quality full size concert instruments excessively stretched? Is this a tuners habit bred of exposure to too many smaller instruments in our formative years?

Yes, the necessary stretch is built-in to the instrument itself. You have just been looking at only one set of partials. An instrument defines its natural necessary stretch by the entire partial series and how it curves upwards. Further priority is defined by what type of music is being played and the intervals most prized; whether that is the octave, fifth, fourth, third, etc.

On very small pianos it is especially important to tune to the whole tone, because nothing locks into alignment perfectly. Tuning to one set of partials leads one astray then from all the others.

To RXD, I can't believe how one habit in tuning small pianos could lead to another, but I suppose it would be possible. The tuner's brain would have to be turned off.

I consciously tune higher relative stretch on large pianos, but higher real stretch on smaller pianos. Small pianos are very sensitive to stretch. There is a tiny zone where they sound 'decent'. Any variation from that window and they sound horrible. For this reason, I view them as 'in the trenches' practice to develop even better tuning technique.

Large pianos can accept a comparatively wide range of tuning variability due to their shallower iH curve. A match at one partial causes a smaller deviation at another. There, one can tune a stretch at one partial, that relative to the movement elsewhere is very wide, but smaller cents-wise than on a smaller piano.

I want to add that from experience tuning both large and small pianos, the small pianos tend to sound flat even with large stretch because of the higher order partials demanding even more stretch still. Octaves must audibly beat on a small piano to eliminate this 'flat' effect.

I agree with you RXD, that small pianos cannot be used as a tone reference, especially to other instrumentalists with flatter iH curves, like the low-tension stringed instruments or woodwinds. The difference between the curves is too severe to align even a unison with good precision.

Thanks all for the feedback..

Just been researching, the next octaves up from F#4 seem the most challenging to set, just slightly wide checking with proportional P4 & P5. Next set as double octaves with 5th check. With this small piano I will try high treble with single octaves - 5th check, to stretch it as much as possible... Does this make sense?

Thanks,
Jim

You may want to try the perfect fifths, it will stretch things out fairly well.

For these small pianos, when you get to C6 (two octaves from the top note) and above, play all octaves and fifths below the note being tuned and just let your melodic ear guide you to the pitch that sounds right. If you then try a single octave, you may be surprised to find some substantial width in it. However, consider two important factors: How long is the sustain in those upper octaves? In which context are those keys normally played?

The higher the pitch, the more inharmonicity there is on any piano. The smaller piano may not differ very much at all from a larger piano in that area because either one will have about the same speaking lengths. The smaller piano will have higher inharmonicity in the lower midrange and bass because of shorter speaking lengths.

What others have said is true: If one set or partials match, all others will not match. Therefore, when tuning upwards from the midrange, if you tune very pure octaves, the octave-fifths, double octaves, double octave-fifths and triple octaves will all be narrow. The wider the interval, the narrower it will be.

Since the small piano has higher inharmonicity in the midrange, this makes the above problem worse. So, it stands to reason that those who tune almost exclusively larger, concert type instruments will say that they don't put much audible stretch in the upper octaves. They don't need to.

For the smaller piano however, you will definitely make it sound better by starting the temperament octave a little wider. Construct the temperament octave with a slight beat in it. Then, as you progress upwards, deliberately force a slight beat in the single octave but compare that with the fourth and 5th below it. Don't let the fourths get too busy. However, by the time you get half way into the fifth octave, the fourths can no longer be heard. If they cannot be heard, it doesn't matter how wide they are!

By the time you get midway through the fifth octave, (F5), you can concentrate on making double octaves and octave-fifths both sound virtually pure. By the time you are able to tune triple octaves, making them sound good to your ear will be more important than purity in a single octave.

What Bill says above was VERY helpful as a way to continue educating myself. FWIW

Thanks very much,

I will try this, very satisfying to hear the positive effects of this, thanks for sharing your wisdom

Jim