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I have recently acquired a 6'4" Chickering from the 1920's. Despite its age, the piano had a really nice treble, with no discernible loss of sustain in the "usual suspect" register. I contracted a local technician to regulate the action and voice the hammers. The work was done in his shop, with final adjustments and tuning completed at home. When all was finished, I tried the piano and discovered to my dismay that the sweet tone in the upper treble was gone: the sound was so anemic as to be almost unrecognizable. I also noticed that the hammers were not hitting the strings squarely in the center: some were misaligned so badly as to miss one of the outside strings entirely, while others were hitting it with the edge. Even the bass hammers were positioned somewhat diagonally to the strings. Do you think this could have caused the loss of tone?

Call the tech back and let them know of your disappointment. Were you present when the "final adjustments" were done in your home?

Are the old string marks in your hammers still there? They should align with the strings. As Terminal degree said, call your tech back. Sounds like you have a hammer/string mating issue, and that is something the tech should have made sure is right. It also sounds like the hammers aren't positioned right. Do some hammers have more space between them than others? This should be easily adjustable by your tech.

Good luck.

Thanks for your input. I was at home at the time, but didn't observe the work being done closely. The hammers have been filed and presently have no discernible grooves to match the string strike points. The tech is coming back, albeit not too happily: his response was that most of the time he'd spent here (about 4 hours) was devoted to this task, and that's as good as he was able to get them to align.

akin,
So sorry you are having technician issues. I suggest describing your complaint as one centered around the tone. Tell the tech the tone is way worse than before he/she worked on it.

Let them find the solution. Let them guarantee it. If you give specific instructions on the type of work to remedy the problem, you become responsible for the outcome.

Try manipulation the sustenuto pedal to slightly shift the action and notice if the tone changes. It might give an indication of hammer alignment. But regardless of the effort the technician put in, hammer misalignment is unacceptable.

Of course I meant the Una Corda pedal (shift). I apologize for the mental mistake above.

If the alignment is off across a large degree of the piano, I am wondering if some adjustments were made without the cheek blocks in place, or, if the piano is without alignment pins on the side of the keyframe. If the whole keybed is canted, there will be bad hammer alignment and the tone will suffer.

Not knowing how you characterize sweetness, perhaps there was a component of brightness you liked before the work and after reshaping heads he needled the hammers too soft for your liking. The solution could be a little of both but if the hammers lined up before there is zero reason they shouldn't line up now. Once that is corrected the tone can be solved.

There really should have been a shop visit and approval before delivery to the home. Then all the problems found could be addressed before final payment and delivery. Then you would still have leverage. Now, who knows how this will play out because all of those problems you report sound amateurish not professional.

Good luck.

-chris

Sorry to read about your misadventure.
(Over) voicing can definitely result in loss of brilliance.
Regarding hammer position and spacing - I would be surprised if your technician removed the bass hammers (or any other) as part of a usual regulation and voicing. I believe most techs would have limited any removal/re-gluing to hammers that were noticeably loose, where the glue joint was failing. As to being (a bit) on a diagonal in the bass, that's something I've seen, and it hasn't been associated with a sound problem (though, I suppose in extreme cases, it could).

On the treble hammers, here is a simple tool that I made out of a coat hanger that I use. You catch the small end under the hammer shank (carefully, of course), and raise the hammer to touch the string.


You might make a 2 column chart going from 1 - 88.
Lift each hammer, note whether it is R(ight), C(entered) or L(eft), and enter the value in the 2nd column.
When your tech comes back, hand it to him or her.

FWIW - spacing & alignment aren't the whole thing with voicing. There's also leveling the strings and ensuring that the hammer is striking all the strings flat on. The little tool I made helps with that too. If you hold the hammer up against the strings and pluck each with a guitar pick (better than a finger nail since it keeps skin oil and moisture off the string), you should be able to notice if one or more strings sound different from the others. In this case, there is leveling work to be done. Again, you might add a 3rd column to your chart and list any keys where there are differing sounds.

Hope this is helpful.

I was recently reading the chapter on voicing in Pianos Inside Out. It seems like the strings need to be leveled before hammer seating/alignment is considered just as Seeker has mentioned above?

That is usually the recommendation I see. Usually it's done by massaging the wire near the agraffe with a string hook to pull a low wire up. However, I've read that strings tend to settle back to where they were due to the string tension, so any change would be temporary. I'd be interested to know what the techs here think about that: level the strings, or sand the hammer to fit?

Whether there is any "room" left to bend a low string higher to achieve full unison phasing depends on how it was worked on previously. Some people yank the strings up to help settle down the pitch quicker and there is little to no more elasticity available to raise the low strings when tone regulating.

I have not found lightly "bent" strings creep back down over time.

I use sanding the hammer to get full phasing as a last resort.

What is interesting is one would think that over time as the hammers are used they would "wear" in to fit with the strings. But they don't! You can check well grooved hammers and they will have uneven unison striking.

Akin,

Even moderately decent quality work of this sort should leave the hammers correctly aligned and spaced such that they are striking the strings squarely. This is a large part of why hammers get reshaped anyway...so that alignments can corrected. Your description of things indicates that the "tech" does not (1) understand these issues, or (2) does not care. The fact that he is not too happy about returning to correct (after spending several hours supposedly doing this) leads me to believe that (1) understanding is largely the problem (and hoping no one would notice).

I have observed this inability to align and travel hammers CORRECTLY too many times, and even with techs who I thought should know better. It is actually quite simple IF you understand the principles involved. However a cursory knowledge of it will make a mess.

If I may ask, what was the charge for the "work" done, and what were you basically told was going to be done? An exact figure is not necessary. Just between $xxx and $yyy (or $x,xxx and $y,yyy) is sufficient. The reason I'm asking is to just get a sense of perspective on the matter. It does matter.

I will say this though: hammer reshaping ALWAYS changes the tone of a piano, but just like anything else, there are levels of quality associated with this that also affect the tone...good shaping vs poor shaping...good spacing vs poor spacing...good attention to detail vs poor attention to detail...etc etc. Attention to detail in a craftsmanlike way is going to ultimately result in improving the sound of the piano.

You are correct to have checked out his work. It would be even more instructive to see a photo of the hammer work with the action OUT of the piano. This will tell us more VERY quickly. Maybe you can do this when he returns.

Peter Grey Piano Doctor

Speaking of hammer alignment, I'm finding that putting pre-drilled hammers onto my existing shanks results in a very uneven hammer line as you can see in this pic. The bore hole matches the shanks and seem to fit well. But some hammers are high and some are low. Every other hammer is glued, and most of the uneven ones in this picture are still loose. I find that I can usually adjust the hammer to be more or less level with its neighbor, and with glue applied, it tends to stay where I move it to. Sometimes it wanders, but if I move it again when the glue is half cured, it stays.

Do you guys have this issue, or are your hammers usually all level before you glue them? I'm thinking it's because of the old shanks not being completely uniform. Perhaps next time I'll buy new shanks and hammers together.

Emery,

1) You need to give the boring specs to your hammer maker including shank diameter for best fit

2) You need to make sure your strike line is accurate

3) You need to trim the shank lengths as needed

4) You need to use an adhesive which can have it's viscosity and set time altered

5) You need to have your action horizontal when working

6) You need to have some form of straightedge guide for hammers and shanks


That's about all I can think of at present.

Peter Grey Piano Doctor

To keep hammers level, glue the end hammers in each section in place, and then use straightedges to hold them aligned while the glue sets, one near the widest point on the hammer head, and another at the shank.

The usual recommendation to replace every other hammer has never worked for me.

On an upright the hammers aren’t drilled all the way through like a grand. If you get too much glue in the hole the hammer might not bottom out in the shank. Especially if the bore fit is too tight. There are shank knurlers that put cross hatch grooves on the end that allow glue to escape.