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Once more I find myself canvassing the collective wisdom of PW to help diagnose a problem with my piano. For the previous case, complete with details on the piano and its history, see here.

The piano was tuned last Friday and the tuner-tech did some surface filing of the hammers to take the edge off a very harsh upper tenor and treble section when played at mezzoforte or above. Today I discovered one of the notes giving off what I can only describe as a 'smacking' sound, a bit like the sound of stiff paper if you flick it or hit it with a pencil.

Here is the link to a YouTube recording of the offending hammer, the third into the treble section. I play the surrounding notes so that the contrast is clear, though the sound is so odd and distinctive that this was probably overkill.

Recording was using a Zoom Q2HD (in stereo) and though the sound is clear over weak laptop speakers, it is striking on headphones or proper amplification.

Does anyone have any ideas what this might be? A crack in the head or shaft? Or just the result of bad filing of the felt?

With thanks in advance,

P.

Just listening on my iPhone, it sounds like a loose hammer to hammer shank glue joint or a loose centerpin.
Things like this can present themselves at any time and are a common enough occurrence.

Technicians should be able to identify the problem better than I can - as rxd did while I was listening.

I can hear the difference but more than one note sounds a bit inconsistent to me on my laptop's speakers.

Voicing may well be the answer but I'd still check to make sure the hammers are aligned to the strings, the flange screws are tight / pins not loose, and the strings are well seated at the v-bar and bridge pins. Presumably the technician who is coming to voice the piano will attend to all that.

What does the tuner who came on Friday say?

I’m no piano tech, but it sounds like a hammer to string alignment problem to me... like the hammer is not hitting all the strings at the same time or they are not level/aligned/mated.

Tone building/management and voicing are very important skills that not every tuner has…

Good luck with it.

Rick

Yes. There are tonal problems on all the notes played. The OP is talking about the 'smacking' sound. You will hear it immediately as a difference in the starting transient of the note in question.

Thanks rxd. I'll pull out the action tomorrow and have a look to see if I can identify either of these.

P.

Thanks Ian. I doubt whether this is a voicing issue as it is an entirely new sound which wasn't there last night and appeared today. Having again compared the recording with the real thing, I realise the recording doesn't bring out the sound of 'smacking paper' clearly enough, even if it does show the difference between the problem note and the others. It's also only an impact sound, independent of the strings resonating, though I admit this is not so clear on the recording (so much for the Zoom Q2HD Stereo!!). I'm still waiting for the tuner to get back to me, but he may well have to come an hear for himself unless I can engineer a better recording.

P.

That's precisely it, rxd. And that's probably why it is not as clear on the recording as it could be, given the difficulties of recording transients on digital recorders. That's an impressive set of ears you have, sir!

Thank you.
No need to remove the action. The hammer will probably have some play in the glue joint and can often be pulled apart with just the fingers. If it doesn't come apart easily, special tools may be needed.

If it is the pinning, (the sounds are remarkably similar) there may be no other symptoms but the hammer assembly may have some play side to side. If the centre pin is actually coming out, you will see the pin shining between the flanges.

The pinning is really a job for an expert. The glue joint, of it comes apart easily, is readily apparent to fix but a professional would align the rest of the nearby hammers at least and tighten the flange screws before glueing in order to get the alignment correct first time.

I was wondering about the sound of stiff paper! Now I can just hear it with my headphones on, but only because I've been told what to listen for.

Rick and I can be excused. Experienced tuners acquire enhanced powers to distinguish sounds, a fact establised by recent research at University College London. It caused quite a stir at the end of August.

Its hard to tell much from the video. A good look at the strike point usually tells the story. And, how the hammer bounces off the string when played at different dynamics usually confirms the condition of the strike point. From what I can pickup from the video:

First; the unison is out.
Second; before you do anything, re-glue the hammer head to the shank. It can be tight on the shank and still click. This slight movement throws off the hammer head alignment.
Third; check that the strings are level and then that the hammer is mated to the to the leveled strings.

These steps should solve the problem. The hammer travel looks ok, so I doubt it's a travel or alignment problem caused by poor flange centers. It helps sometimes to re-seat the hammer flanges by loosening and then re-tightening the screws.

And always check for loose back check catchers.

PNO40,

To add another perspective to what's already been written: if this were my situation, I'd consider changing to another tuner. In my opinion, given that the tuning is only a few days old, the quality of all those unisons (with the possible exception of the fourth one, A5) leaves something to be desired, especially G#5 and A#5.

By the way, I also hear a little click on A5, but this one happens just before the hammer strikes the string, i.e. when the action starts moving. One can hear it both on the upwards (0:14) and the downwards run (0:18). I doubt that it's your fingernail on the keytop, because it's not evident on any of the other notes.

Just to clear up a few red herrings on here.

This Is mechanical noise, traveling faults or faulty hammer /string mating does not make a mechanical ('smacking') noise on the attack.

An owner is unlikely to be equipped to remove a hammerhead If it is on tight but clicking.

A loose flange screw has a deeper, more complex click, a loose Catcher clicks almost the same but after the attack.

Nor were we asked to critique the tuning since we don't know the entire story.

What's that wonderful Abraham Maslow quote somebody uses on here? 'if the only tool you have is a hammer, every problem looks like a nail'.

rxd, what your saying is true. But as your siggy sayz, "in theory, practice and theory are the same thing. In practice, they're not.".

Which might explain why I have experienced 'smacking' sounds similar to the ones on the video from an out of tune unison with unlevel strings and poor hammer to string mating.

After a few seasons of humidity fluctuations, the flange contact to the Hammer rail may not be flush. Hence the suggestion to loosen and then re-tighten the butt flange screw. It is clearly not a diagnosis to the clicking problem, but is something that could contribute to the click sensation.

Both the flange and the butt catchers, although usually a lower pitch and more complex, do come in different pitches and complexities.

I know we were not 'asked' to critique the tuning but, the tuning effects many things in a piano. Often sensations perceived as buzzes and zings, are produced by poorly tuned unisons on strings with uneven travel tensions.

Noises and uneven attack can be a symptom of a combination of 2 or 3 different causes. There is a strong possibility that this is happen on this piano. I'm also hearing a slight metallic rattling as all the notes on the video are played. This could also be adding to the 'smack', especially if the problem note vibrates the rattle stronger than the other notes.

I'm putting my hammer back into my tool case as I await your diagnosis.

Loose hammerhead, or loose hammer flange screw. Very characteristic sound.

--Cy--

Well, I was hoping that on a forum such as this, there would be an opportunity to comment on the quality (or possible shortage thereof) of a tuning that is only a few days old - in the interest of striving for the best possible service to the OP. But if I offended anyone or confused the issue by commenting on something that was not asked for by the OP, I apologise for my part in any "red herring".

I have already given my diagnosis and others have spoken on these issues far more eloquently than I. The sounds are easily distinguishable to an experienced tech.

What I really take issue with is our right, as respondents to go so far as to recommend the OP to get another tuner when we don't know the entire circumstances. For example, what is the state of the pinblock? What were the time constraints? How much pitch raise was involved? And that's just for starters. None of us, none of us, repetition intentional, know the circumstances.

Judgements of this nature, made from a point of view of ignorance of the circumstances, say more about the person making the judgement (and their upbringing and education, because they have never been taught this elementary principle) than they do about the OP's tuner. I have a lot more to say on this if anyone is interested.

Lecture over.

Quiz time.

Somebody heard a slight tick sound on a key in this video like the click of a fingernail on a key but it was not that.

Question, What else is it likely to be?

Loose nut on the keystop stick or a loose damper wire adjustment screw on the damper flange

Possible, but I'm looking for a sound even more similar to a fingernail hitting a key and with the same timing.

Loose keytop.