Notes rising in pitch

[661-Pete]

Some months ago I posted about my attempts to re-tune my ancient Viennese upright (Gustav Stingl, dating about 1895). I think I got some sort of result out of it, although my amateur efforts would not match up to a professional tuner's of course! But the notes are all there, I got away with just one broken string, I don't hear discernible beats in the unisons. So I think I've learnt something, and it's certainly taught me to listen to the piano instead of merely playing it.

But what I am getting, and I think this effect was there before, is a rising of pitch when I play, especially a bass note, forte, and then hold it. This rise comes after about a second and is very noticeable, about 20 to 30 cents.

Can anyone explain this phenomenon? Obviously the strings, especially the wound ones, are not in the best of condition, rather dirty and rusty.

I'm half expecting that this problem can't be solved and that it's time to invest in a new piano...

[Colin Nicholson]

Hi there
Well done for tuning your piano.

Assuming the pitch is set at C523.3Hz (or A440 equivalent of Concert Pitch) / or whichever pitch you have chosen.... a one-off attempt at tuning for the first time is just the start of your tuning (stage1) - a once over is never enough, especially the age of the piano, and when it was last tuned. As you start to bring the pitch up (or drop it), you will also be inadvertently changing the pitch of many "untuned" notes.... this is down to the soundboard & bridges changing shape, and adjusting their crown to cope with the sudden changes in tension.

If you have just finished tuning the treble end first, then move onto the bass, as you are tuning the bass, the treble will already have 'moved' and changed pitch - even just after being "tuned".... not uncommon, so if the crown of the soundboard expands.... this will stretch the strings and rise their pitch. Here is the routine >>

1. Very roughly (and as quick as you can) change the pitch .... leave it a short period to settle - out of tune.
This is known as a pre-tuning/ rough tune. Takes about 20 - 30 mins.

2. Re-adjust the pitch again, get a closer tuning/ unisons/ octaves/ ET scale.... leave it a few hours. 1 hour
3. Fine tuning..... going back and making small & final adjustments. 1 - 1.5 hours

Total time about 3 hours.

If you are inexperienced at tuning, as you may be taking longer to pitch raise than a pro.... this will have an effect on the final result & overall tension taking too long to adjust - the key thing for pitch raising is speed during stage 1. Start in the middle, work up to the treble. then work down through the bass. Depending on the condition of the tuning pins/ wrest plank and strings, the pitch should hopefully settle after about 3 tunings.

Newly strung pianos are tuned about 10 times.... taking about 18 months to settle down. Each tuning eventually becomes more mature.... be patient though, and you will hear the results.

[661-Pete]

Thanks for your good advice Colin; I did in fact make several passes through the piano, spaced over several months. I admit I'm rather slow compared to the professionals!

But this doesn't answer the question, why my bass notes (and even, to a slight extent, the mid-range) vary in pitch whilst being played. Is this something that a re-tuning will eliminate?

[Colin Nicholson]

If you are using the incorrect lever movement technique and not 'dropping into pitch' correctly - by means of setting/ flexing the string & pin, then all your work will be partly wasted. By also hitting the note harder & partly flexing the tuning lever will get a more stable tuning. Also, always go sharp first, then drop down into pitch - don't just go up the pitch and leave it there, otherwise it will quickly drop. Of course, a very old piano, so if the pins do not have sufficient torque (combined with an amateur lever technique) and condition of stretched strings, then don't expect to stay in tune for long.

Maybe a good idea to book a tuner, watch their technique & get a few tips.... once it is tuned properly, then you could always tidy up any unisons at a later date - in keeping with the temperament scale.

Broken string?? .... best to get that replaced, or it may damage the hammer head and flange or butt if pressure on one side due to missing string. If it's a bass bi-chord that is broken, need to replace both, otherwise new & old will not tune together.

[vernon]

sounds very wafty to me.
Are you saying that during playing the notes in the bass alter?
Do they go back after the recital or do they need retuning?
Are they out of tune after playing?

[rxd]

This is a phenomenon that is not unusual. it can be replicated with any electronic instrument with a continuous sustaining note and a volume control. A sustained note can appear to rise in pitch as it gets quieter. This naturally happens with a piano note. Much depends on the tone quality of the note but it can be heard to a greater or lesser extent on most medium or lower range notes. It may be more apparent to different people in different registers. It is not a function of the piano being tuned but may be more noticeable because you have started to listen closer. Try higher notes. You may notice the same thing but to a lesser extent. They don't sustain as long.

[Colin Nicholson]

I think it might be just the general age of the strings being about 120 years old. It is likely that certain individual strings will give off all sorts of 'wolf' tones and overtones.... combined with over-stretched and 'pear shaped' strings/ odd bit of tarnish etc.... explaining something like this can only be effectively answered face to face with the piano by a tuner. I tuned an old old grand recently ---- gave off all sorts of weird & wonderful tones, and even certain single treble strings muted off sounded out of tune within themselves. A good piano to practise on (and best breaking strings on these).... but not a good piano to use as a lecture for fine tuning.... with respect

A piano I recently re-strung.... I demonstrated to the customer by listening out for partials between Middle C down to F. "Can you hear the slow triplet beats?" .... "NO!" .... so this went on for a few minutes as I was making monkey noises at the customer "wa wa wa" and then pulling the lever to quicken the partials, then slow then down.... "YES, I can now hear what you are on about" .... I know I should be locked up, but at least now the customer has a brief understanding of the Equal Temperament Scale !!