Sneek Peak at Piano Tuning Theory Book – Chapter 3.6 – Cents

CLICK HERE to read this chapter of my book, Piano Tuning Theory.

In this chapter I develop the common formula for calculating the cents difference between two frequencies.

The book is targeting piano owners and technicians who may not have a strong mathematical background, but are still interested in the theories of piano tuning.


You can pre-order the book HERE

Pin Block Repair

I recently inspected a piano with a birdcage action. The customer was very excited to get it working. I told her it would never work great. She understood. 



I gave her an estimate and she agreed on a schedule. 

Then I opened the top and saw one of the largest pin block frame seperations I’ve ever seen. 

This is the separation after a no glue repair. 



I gave her the price for that and she said go ahead. 

I’ve seen pin block repairs before that were not glued and decided to try the no-glue repair on this piano. There were eight holes for bolts so that was good. 



I measured and tried to get bolts that were just long enough. I did not want to start grinding bolts off. 

I decided to have the bolts go out the back but you could do it the other way around. We will add a piece of wood trim to stop the bolt ends from scratching the wall. 



One pin was very close to the bolt. I had to remove the pin, insert the bolt, and re-insert the pin. 



After bolting, we added CA glue because the pins were loose. 

Now we’re tuning it up to see how high she can go. A tone flat and already one bass string broke. The customer was made aware of that possibility. 

The goal is to get it so that each note is working and she can play the piano and it sounds as musical as possible. 

Sometimes we have to remember that we are servicing the customer and not just the piano. ?

What’s Happening?

Happy Canadian Thanksgiving to all my subscribers and way to go Bluejays!

I’m posting on my site tonight, realizing that I haven’t posted here in a while. The reason why, is that I have been posting on other public forums. The nature of my posts on those other forums has been to share my piano tuning and repair methods with other piano technicians.

I’ve been doing this for a few years now, and while I receive positive feedback from many, I also raise the ire of many as well, to the point of being called a “piano butcher”, a charlatan, and deluding people, when all I am doing is relaying to other people the way I am doing something. The results, from my perspective as a Registered Piano Technician, and piano playing musician, are acceptable at least, and often impressive. But for some reason, my posts bring out the haters.

I’ve known for a while now why I post on those other forums. You see, about a year ago, I took an online test to see if I was a narcissist. While the average was 19/30, I scored 5/30.

I am insecure. Often, I have been posting on other technician forums because I am looking for validation of my methods.

For this I am ashamed. Ashamed because I have ignored the positive and glowing feedback of my students and my customers. Ashamed because I am looking to strangers who are my competitors, to find confidence.

And ashamed because I have not had the confidence in my own results. How can I expect others to have confidence in my own methods, when I don’t?

So, today I pledge to never go looking for validation from strangers again, many who are insecure in their own abilities.

I came to the realization today, while reading some posts on aural piano tuning methods vs ETD methods, that I will never find widespread acceptance of my methods. The reason being, is that my Beat Speed Window method is too empirical. Too many aural tuners tell of tuning by feel, with no consideration for empirical feedback, like those obtained by using beat speed windows.

When so many tuners are now using, and some revering, the results of machines, machines that use math to tell us what the best tuning is, math that uses approximations and error data as input, you would think that using a scientific and empirical aural method would be welcomed.

This has not been my experience. For the last week I have contemplated posting a few times about my empirical beat speed window method, but after receiving little or no interest from previous posts, and fielding a bombardment of criticisms which, by their own wording, show that some tuners have too easily chosen to leap at an understanding of the method that makes it look weak or even foolish, instead of assuming that they themselves may have a misunderstanding of the method which they obviously do, I have quickly abandoned the idea.

So, the challenge remains. How do I spread the word about a new aural piano tuning method that produces highly accurate and precise results, using a technique that only a few ingenious technicians have ever used, but that I have been able to package within a set of procedures that make it user friendly enough to teach to beginners?

Beat Speed Windows with Double String Unisons produces
– Consistent and accurate stretch that produces the most number of pure intervals,
– A method of valuable and high resolution feedback that fast tracks the tuner’s understanding and ability to produce clean unisons and superior stability
– An accurate and precise temperament right from the first setting of a temperament note, producing pitches that are the final pitches needed for each note.
– A method that catches drifted notes before they are needed as references to tune other notes.
– A method that asks the tuner to tune specific beat speeds within windows, instead of guessing what they should be.
– A way to perform one pass pitch raises that require the tuner to keep creating accurate pitches instead of guessing at over pulling,
– A way to speed up tunings incredibly, without having quality suffer.

There is no way I can explain all these things in one post. In fact, even after people take my basic tuning course, which now is taught using this new method exclusively, there are elements and understanding that are missed.

So, the question remains; how do I spread knowledge about an aural piano tuning method that I know is superior to current methods, can produce precise results, as precise or better than any modern ETD, and I know this because no tuner, programmer or not, is aware, or if they are aware, is convinced of the superior criteria I place on beatless octaves and pure interval stretch.

The only answer I can come up with, based on my recent years of developing this method, enjoying its beautiful results, and sharing with other technicians is…slowly.

Please comment and keep in touch.

Please ignore the last blog post

Hey Subscribers,

I just realized that I inadvertently sent out a garbled page/post that was part of my new Ear Training for Piano Tuners course. Just ignore it.

If you are interested in trying out my new online ear training course for free, just CLICK HERE


Hooke’s Law and this Long Non-Speaking Length (NSL) Mean I Have to Turn the Pin Quite a Bit Before the String Slips Across the Agraffe and The Pitch Changes. 

NSL analysis is invaluable in figuring out what to do in these unusual cases in order to acheive a stable tuning. 

Hooke’s Law

DSU Saves Time by Allowing You to Tune a Piano Without Taking it Apart. 

Reblitz Upright Regulation Steps Modified

Piano Servicing, Tuning, and Rebuilding: For the Professional, the Student, and the Hobbyist by Arthur Reblitz is the standard text I recommend for my Basic Piano Tuning and Basic Piano Repair courses.
It is an excellent resource for repair and regulation, although I find it a bit weak on tuning. (That’s why I wrote my Basic Piano Tuning Course Manual)

However, the upright regulation steps listed in Reblitz, have room for improvement.

Some steps refer to adjustments that usually don’t need to be done if they’ve been done already, like positioning the let off rail. Some steps refer to adjustments that could make things worse, like changing the back checks. (It is not as critical, and if they are all in a straight line, adjustment may leave them not as straight.)

Also, instructions are given to set all the blow distance at once. Same with key dip, and let off. I was taught to set a few samples first, in order to confirm the ideal blow distance, let off, and key dip that produces appropriate aftertouch for that piano. (I call blow distance, let off and key dip, the Regulation Triangle and I’m writing a book on how to regulate a piano using this method. See Regulation Triangle Method for Easily Understanding Upright and Grand Regulation)

If you are interested in reading my full modifications for the upright regulation steps listed the Reblitz book, just enter your email HERE.

The Secret to Tuning a Piano by Ear

A recent poll suggested that 90% of professional piano tuners use a machine to help them tune pianos while most agree that you need aural skills to tweak the machine.

The piano tuning exam to become a Registered Piano Technician (RPT) with the Piano Technicians Guild (PTG) still requires examinees to tune part of the piano by ear, and many still fail that exam.

I have been teaching aural piano tuning since 2005 and since that time, I have be fascinated by how people learn to tune pianos by ear, and I am passionate about finding the best way to help people learn this skill easier.

Piano tuning has been around for a long time, yet the field of tuning pedagogy still seems young. There are schools and instructors still teaching methods that were taught 100 years ago. I find it interesting that few schools and instructors make use of technology to help students learn how to tune a piano by ear, instead of just using a machine to tell you where to put the pitch of each string. I make this observation based on the fact that at the time of this writing, no formal schools had any YouTube videos describing any of their methods. Actually, most had no videos at all.

Since I teach short courses about aural piano tuning, my methods have to be as succinct and efficient as possible. I have spent my entire career looking for specific skills that are necessary to learn this craft, while weeding out the myths and incorrect information, often perpetuated by professional technicians, that gets in the way.

Here are the three specific skills that I have identified as the most important skills needed to be able to tune a piano by ear. In fact, if you haven’t got all these, your aural tunings will be poor.

1) The ability to focus the ear, at will, to specific frequencies, filtering out all unwanted frequencies, in order to make accurate judgements on where the pitch of a string needs to be.

2) The ability to change the pitch of a string by the smallest of amounts, thereby zeroing in on the precise pitch that you know the string needs to be, based on your skill in #1.

3) The ability to tune a string to that specific pitch, and have it stay there, even when the pianist plays the note fortississimo.

If you have these specific skills, all you need is an accurate and precise procedure, or method, in order to produce high quality aural tunings that sound beautiful. My Double String Unison (DSU) method is one way to do this. It contains a complete set of instructions, based on beat speeds, that tells the tuner exactly where the pitch of a string needs to be.

For example, many aural piano tuners advocate tuning midrange octaves as wide 4:2 and narrow 6:3. (I’ll explain a bit more about what these are later, but an indepth discussion can be had on this subject, and is in my courses.)

Now, in very simplistic terms, we will listen to two intervals. They will be beating at a high frequency. If the 2nd interval beats faster, it is wide.

You will hear two pairs of intervals. The 1st pair will be the test for the 4:2 octave size. The 2nd two will be the test for the 6:3 octave size.

The Wide 4:2, Narrow 6:3.
In this video, you will first hear four intervals. Listen for these relative beat speeds:
1) This beat speed is the reference for the 4:2 size.
2) This beat speed is slighter faster than #1, indicating a wide 4:2.
3) This beat speed is the reference for the 6:3 octave size.
4) This beat speed is slightly slower than #3, indicating a narrow 6:3.
Then the actual octave is played.

The iPhone app, Soundbeam, allows us to zero in on the exact partials that are beating and actually see how they beat. We can even get an idea if one is faster than the other, even if we can’t hear it.

In the views below, the 4:2 partial is the first peak, and the 6:3 partial is the 3rd peak.

Many standard methods advocate that the octave should tuned as this one is; a wide 4:2, narrow 6:3. Listen and watch as the wide 4:2/narrow 6:3 octave is played (5th interval). Listen and watch as the 4:2 and 6:3 peaks are beating when the octave is played. A pure interval does not have any of this motion or beating in the upper partials. This octave does not sound as good as the next one.

The Pure 4:2, Very Narrow 6:3
Watch and listen as this pure 4:2, very narrow 6:3 is played. Here are the 4 intervals and their relative beat speeds:
1) This beat speed is the reference for the 4:2 size.
2) This beat speed is the same speed as #1, indicating a pure 4:2.
3) This beat speed is the reference for the 6:3 octave size.
4) This beat speed is very much slower than #3, indicating a very narrow 6:3.
Then the actual octave is played.

Watch and listen to the 4:2 partial (1st peak) and the 6:3 partial (3rd peak) as the octave is played. The 4:2 partial doesn’t move (beat) much while the 6:3 partial moves (beats) quite a bit.

Common methods tell us that this octave should not sound good, but compare its sound to the wide 4:2/Narrow 6:3 above. The pure 4:2 octave clearly sounds more pure, even though the 6:3 is beating wildly. I believe it is exactly this fast beat that allows our ear to ignore it.

I am NOT saying the pure 4:2 is always the best size octave for every piano, it isn’t. The actual size that sounds best on a piano depends on the inharmonicity of the piano strings. The DSU method has a procedure that shows you how to aurally measure the inharmonicity of a piano’s strings, and determine what size is the best for that piano.

See Tuning Beatless Octaves

CLICK HERE to watch a video that describes the DSU method in more depth, also called the Go APE method.

Dampp Chaser Pads – Before and After

Here are some photos of Dampp Chaser pads on a piano I serviced today.

I thought you might find it interesting to see the quality of mineral deposits That the pads can collect.

Surprisingly, the pads still wicked water, but I changed them anyway.



Notice the water line just rising on the right pad.

Relative Humidity

Relative humidity (RH) is a term that piano owners are concerned with because too much or too little is not good for a piano, being made mostly of wood. Excessive humidity can cause metal parts to rust, and wood to swell. Too little humidity in the air and the wood parts can become dry and brittle, and crack or split, and the glue joints can fail.

As piano technicians, we advise that the piano be kept at 42% RH, but it’s actually the wide swings that can cause more damage.

RH can be a difficult concept to grasp, as witnessed by a recent exchange I had on a piano tuner’s forum where some posters were actually quite angry with me for saying that cold air can be more humid than warm air.

I understood their reaction becasue this is counter intuitive; common experience says that cold winter air is drier than warm summer air.

Before explaining my comment, let’s take some time to discuss exactly what relative humid is.

What is Relative Humidity?

Air can hold water. Hot air can hold more water than cold air. Relative humidity is the amount of water in the air, relative to amount of water the air can hold.
See Wikipedia article HERE

Consider an air mass that has a constant amount of water in it, at different temperatures.


The fraction of Actual Water to Maximum Possible Water is clearly higher in the cooler air.

In other words, cooler air has a higher relative humidity than warmer air with the same water content. Counter intuitive, but true.

Take a look at the data I recorded in a simple experiment. I took a hygrometer, which measures temperature and relative humidity, and put it outside on a warm day. I recorded the temperature and humidity and then brought it inside our air conditioned home. If the cooler air conditioned air, did indeed have less moisture than the outside air, then common knowledge says the cooler air should be drier.


Clearly the cooler air was more humid. (Any error in the exact RH measurements is moot since we are looking at the relative measurements, not the absolute measurements.)

Here are photos of the hygrometer outside in the warm air, and inside in the cool air. Time between photos: about 15 minutes.



Air Conditioned Air

Let’s consider the case where we use an air conditioner to cool down the outside air before it enters a home.

For this situation, we must discuss Dew Point.

Dew Point is the temperature at which the air has been cooled so much that, if the temperature goes lower, the air will not be able to hold the current amount of water, and the water will condense out of the air. We can see this water as dew on the cool morning grass after a cool night.
See Dew Point.

Air conditioners have a drain pipe to export the condensed moisture outside, when the air is cooled below the dew point. Just because AC units have this drain pipe, does not mean that the air will always be cooled below the dew point. Let’s consider the situation where an air conditioner is used to cool outside air, but the air is not cooled below the dew point.


In this case, it is easy to see that, for all inside temperatures lower than the outside temperature, the cooler air inside the home will always be more humid than the outside warmer air, if the inside and outside air contain the same moisture.

But what about when the AC unit cools the air below the dew point and condensation occurs?


In this case, there is a point of equal RH where the air is cooler, has less absolute moisture, but has the same RH as the warmer outside air. Any place in the home that is above that temperature, will have more humid air than outside. Lower temperature areas will have drier air. Again, counter intuitive.

The implications of this data have to do with our possible misconceptions with respect to RH.

It is true that pianos are recommended to be kept close to 42% RH, and that swings in humidity are not good for pianos.

But with this new information, some interesting conclusions regarding maintaining a piano’s RH can be deduced.

For example, if a piano is in an air conditioned home, keeping the piano close to the AC unit with the idea that the colder air will be drier and therefore protect it against the outside humid air, may actually increase its RH instead of lowering it.

Similarly, piano owners concerned that leaving their pianos in a cold garage over the winter will dry it out, can be relieved knowing that the cooler garage air may actually be more humid than the warmer inside air, even if the furnace has a humidifier. (There is a chance of wood damage if the air gets below freezing; the moisture in the wood may freeze and expand.)

I was told this stuff by a friend of mine who is an accomplished high end piano rebuilder and technician, and also a mechanical engineer.

When he first told me, I was confused because it went against my common knowledge. But because of my technical training, he was able to easily explain to me why this was true.

I hope that this article, with the links to Wikipedia, and the graphs I produced, will make it easier for you to understand this subject as well.

StudentBlog theme is brought to you by online slot games such as Plenty on twenty, Fruits and sevens and Columbus deluxe.