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Dirk's Piano Tuner

Tuning a piano the classical way is a very complicated process. One has to possess the skills, to handle the tuning hammer in the correct manner and to leave the tuning pin in a stable position. It is however even more difficult to determine the correct pitch of the strings. Many instruments can be tuned using a simple tuning device. Each tone is then tuned exactly to a predefined frequency. This method can't be used tuning a piano. The result would make the piano sound harsh and out of tune. The reason for this lies in the way stringed instruments produce their sound. Dirk's Piano Tuner analyzes your instrument and uses the results to calculate the optimal tuning for your piano in particular. Using this calculated setting, you can then tune your piano, in no time, to a professional level, without having to go through the classical, time consuming, process of 'checking the intervals'.

Piano Tuning & Repair Blog

How to tune a piano

Tune a piano yourself to a professional standard.

Click on the following link for a short manual:

How to tune a piano

Course week 'piano tuning for beginners'
The course is given in the Dordogne in France. During the course you will learn the theoretical and practical steps of the piano tuning process (with the help of Dirk's Piano Tuner). For more information, click on the following link:

Course week 'piano tuning for beginners'

A string can vibrate in several ways. It can vibrate in one whole section; the middle of the string then oscillates and the ends are fixed. It can vibrate in two sections; the middle and the ends are then fixed and the string oscillates on 1/4 and on 3/4 of the length. This way a string can also vibrate in three, four, five... etc. sections. All these vibrations occur at the same time in the string. Each vibration has its own frequency. A struck string therefore provides several frequencies at the same time. These are called the strings' harmonics. When these harmonics are exactly 2, 3, 4 and 5 times the base frequency, then a simple tuning device can be used. For a piano this is unfortunately not the case. For a piano these factors are not exactly 2, 3, 4, and 5. The exact values of these factors determine the base frequencies of the piano strings, that is when the piano sounds most harmonic or 'in tune'. In practice it shows that the low note need to be tuned a bit lower. The high tones need to be tuned a bit higher. The rate in which the low notes need to be tuned lower and the high notes higher is called the stretch of the piano. This means that each piano has to be tuned differently to achieve its optimal sound and performance.

Determine the right stretch
There are already tuning devices that take this stretch into account You can choose a stretch at setup, where a small stretch is chosen for a large piano and a large stretch for a small piano. Such tunings devices can take the piano to an almost optimal tuning. But the specific design of the concerning instrument is not taken into account and therefore some of the factors, that decide the stretch, are left out. Because of this, the piano will not sound optimal and it will still be necessary to determine the best stretch 'by ear'.

The piano technician does this by striking a lot of intervals (two keys at the same time) and aligning them. To do this properly, a lot of experience is an absolute necessity. The difficulty lies in the fact that you cannot tune the intervals entirely pure and the rate of purity is different for each and every interval. When an interval is not entirely correct, one of both notes will be adjusted accordingly. This note however is also part of several other intervals. Therefore all these intervals will have to change as well. All this produces a large complex puzzle that has to be solved.

Dirk's Piano Tuner solves this puzzle for you. In Dirk's Piano Tuner all strings will be recorded by playing them all one by one, only one string per note the remaining strings muted. The tuning (and so is the stretch) is determined by the computer using these single string recordings. The tuner not only records the fundamentals, but also the harmonics. After this 'single string' recording, the tuner has all the data needed to calculate the optimum base setting of all strings. The tuner calculates then the purity of all possible intervals and aligns them. After this the strings can now be tuned one by one to the resulting notes from the tuner. The tuner recognizes the struck string automatically and shows how much the string deviates from its ideal pitch. The muted strings are lateron tuned equal to the earlier tuned string in the same unison. After tuning all strings the piano has been tuned with the best stretch. The piano now sounds as pure as possible for that particular piano. Each note needs only to be tuned once and it is no longer necessary to finish the tuning by ear.

An overview of this tuner's features
Suitable for pianos and grand pianos of all brands and sizes.
Realize a professional tuning easy and quick, exactly tailored for your particular piano.
Calculates the most optimal stretch. Every string gets the optimal pitch.
Save the calculated stretch so it does not need to be calculated again the next time.
Very easy to use. No knowledge of the complicated piano tuning theory necessary.
It is not needed to check intervals and to hear and count beats.
Fast reaction of the needle to be able to tune to the right pitch easily.
Automatic detection of the struck string prevents tuning the wrong string.
Not only the tone is detected, but also its octave.
The needle keeps tracking the tone, also if it moves into another tone.
Take new strings up to the necessary tension, safe and quick.

Dirk's Piano Tuner V4.0

Desktop, Laptop, Netbook, Intel Tablet
iMac, Mac Pro, Mac mini, MacBook
US Dollar

Buy (Microsoft Windows)
US Dollar

Buy (Apple OS X)
Download the trial version

Download the trial version (Microsoft)
Download the trial version

Download the trial version (Apple OS X)
User Manual 1         User Manual 2

User Manual
Supported Windows 10
Supported Windows 8.1
Supported Windows 8
Supported Windows 7
Supported Windows Vista
Supported Windows XP
Unsupported Windows ME
Supported Windows 2000
Unsupported Windows 98

Unsupported Windows Phone
Unsupported Windows RT
Supported OS X 10.11
Supported OS X 10.10
Supported OS X 10.9
Supported OS X 10.8
Supported OS X 10.7
Supported Mac OS X 10.6
Unsupported Mac OS X 10.5
Unsupported Mac OS X 10.4
Unsupported Mac OS X 10.3

Unsupported iOS iPhone
Unsupported iOS iPad

The tuner is available in the following languages:
Nederlands Nederlands English English Deutsch Français
Polska Русский Italiano Svenska Português Português
Español 中国的 Norsk Magyar

The manual is available in the following languages:
Nederlands Nederlands English English Deutsch Français
Polska Русский Italiano Svenska Português Português
Español 中国的


Jahn Piano
Tuning Set Pro

Piano Tuning Tools

Worldwide delivery

Dirk's Piano Tuner V4.0
piano tuning, piano tuner

Automatically calculate the optimal stretch
piano stretch

129 Messages Write in the guestbook  
Name: Gerard
Location: Volendam
Date: 2016-05-22
Language: Nederlands Nederlands
Comment: Dirk, dank je wel voor het schrijven van dit mooie programma.
Een stemprogramma zoals het moet zijn. Goed en makkelijk.
De betrokkenheid en de service van jou zie je niet vaak. Dank daarvoor.
Ook de stemcursus in Frankrijk bij Ben Verbon was een geweldige ervaring.
Zeker voor herhaling vatbaar.
Bedankt en groet,
Gerard Burger.

Location: garlasco (pv)
Date: 2016-04-18
Language: Italiano Italiano
Comment: ho utilizzato il programma su un yamaha c3xa
e funziona perfettamente
unico piccolo neo vi sono un paio di note che "lui" non riesce a discernere nella parte acuta, probabilmente dovuto all'algortimo di riconoscimento della frequenza.. ma dopo vari tentativi ci si riesce

Name: Bård Thomas Hesvik
Location: Haugesund
Date: 2016-04-1
Language: English English
Comment: I'm in the process of getting familiar with this tool, and it strikes me how simple and extremely intuitive it is. In my mind anyone could tune a piano with this tool and a maximum of two thumbs!

I will report back when I'm done tuning the whole piano!

Name: Peter K
Location: New York
Date: 2016-03-27
Language: English English
Comment: I have been using Dirk's Piano Tuner since late 2014. I have tuned my Steinway B six or maybe seven times with it. I was amazed the first time I used it and, frankly, remain so now. My tuning technique has improved dramatically and I can now tune the whole piano in two hours, plus 15-20 minutes setup time (setting temperament strips, etc.) I strongly recommend an external mic All in all I can strongly recommend this product.

Name: Steven Mull
Location: Geneva, NY
Date: 2016-02-29
Language: English English
Comment: Dirk's piano tuning software is by far the best designed, best executed, and easiest to use piece of programming I have ever encountered. Keep up the good work Dirk!

Name: Gary Bishop
Location: USA
Language: English English
Comment: I use this to tune pianos for myself and a few relatives. It does a real nice job. I use to do it by ear, which was too frustrating for me. I am much happier using this program.

Name: Tjaarda MEES
Location: Lemps, France
Language: Français Français
Comment: J'utilise Dirk's logiciel depuis qqs années et j'accorde pas seulement mon propre grand-piano mais aussi des pianos de ma famille et de mes amis. Avant, j'ai réussie à les accorder assez bien (sans aide) mais le résultat est absolutement mieux avec Dirk's logiciel. Le logiciel est facile à utiliser et le SAV de Dirk est splendide.
J'ai également un piano carré et je l'accorde à un autre hauteur, pas de problème avec ce logiciel.

Name: Tjaarda MEES
Location: Lemps, France
Language: Nederlands Nederlands
Comment: Ik heb Dirk's pianostem-programma nu al een paar jaar en stem er niet alleen mijn eigen vleugel mee, maar ook de piano's en vleugels van vrienden en familie. Ik kon al vrij goed piano's stemmen op het gehoor, maar met het programma van Dirk is het resultaat beslist beter. Het programma werkt prima en de begeleiding en service door Dirk is geweldig. Ik heb ook een antieke square-piano en die stem ik op een andere toonhoogte, en dat is met dit programma geen enkel probleem.

Name: Wim Thijs
Location: Middelburg, The Netherlands
Language: English English
Comment: Dear Reader,

I tune my own pianos since 1974 with the help of several tuning divices.
Summer 2015 I was looking for a better tuning device because the built-in stretching of my old device was not satisfying any more.
I bought Dirk's tuning device.
Result: my instruments sound SUPER; better than ever before !!!
Highly recommended !

Cheers to Dirk and Ben for the development of this incredible tool !

Many thanks,

Dr. ir. Wim Thijs

Name: Wim Thijs
Location: Middelburg
Language: Nederlands Nederlands
Comment: Beste lerer(es),

Ik stem al decennia mijn piano's met behulp van diverse stemapparaten. In de zomer van 2015 ging ik op zoek naar een beter stemapparaat omdat de stemming toch niet echt helemaal mooi was met de voorgebakken stretch. Het werd Dirk's stemapparaat.
Resultaat: mijn piano's hebben nog nooit zo mooi geklonken.
Hulde aan Dirk en Ben voor het ontwikkelen en ter beschikking stellen van dit ongelofelijk mooie hulpmiddel !

Dr. ir. Wim Thijs

Name: Caspar Schijns
Location: Nederland
Language: Nederlands Nederlands
Comment: In 2012-02-21 Dirk's Piano Stemapparaat gekocht.
Door computerproblemen en herstel van windows is mijn meest dierbare programma het Piano Stemapparaat van Dirk verloren gegaan.
Na E-mail aan Dirk direct nieuwe installatie software ontvangen
en programma opnieuw kunnen installeren, dit is pas echte After Sales.
Dirk's Piano Stemapparaat is een programma waar je gelukkig van wordt en de piano volledig onder controle kunt houden.
Bedankt Dirk.

Name: Alberto Eliezer
Location: Brazil
Language: English English
Comment: The best tool to tune a piano ever.
The perfect stretch curve for the specific piano makes all the difference!!!

Name: Gjermund
Location: Norway
Website: PopJazzOnline.com
Language: English English
Comment: I'm using the pianotuner program! Very happy!
It works better than many of the piano tuners I've used so far.

I get really good tuning! Also, very good customer support!
Keep up the good work, Dirk


-=Gjermund Sivertsen=-
https: / /PopJazzOnline. com - The number 1 place for learning piano online

Name: CG Johansson
Location: Kalix, Sweden
Language: English English
Comment: I found this program on the Internet in early 2012 and tested a bit on my piano. It seemed easy to make a tuning so I decided to buy to be able to test the program completely.
After some problems in the beginning, which Dirk quickly helped to fix, I now use the program at any tuning.
My laptop recently crashed so I had to get help with the installation of the software on the new laptop. Dirk was, as always, quick with support.
The program is highly recommended and Dirk's support is outstanding.

Name: Hans
Location: Venray
Language: Nederlands Nederlands
Comment: Gebruik het programma sinds december 2014. Resultaat is echt perfect. En het is nog leuk ook om zelf je eigen vleugel te stemmen. Ook even tussendoor een paar tonen bijstemmen is mogelijk als je het zelf kunt dus veel minder ergernis en wachten op de volgende stembeurt van de Pianostemmer. Helemaal TOP!

Vandaag de update voor El Capitan van Apple gekregen na één e-mailtje aan Dirk. Binnen een paar minuten antwoord en de update. Uitstekende service.

Een aanrader.

Name: Frank Tichelaar
Location: Zandvoort
Language: Nederlands Nederlands
Comment: Vorige week de pianotuner besteld en voor het eerst gebruikt. Erg tevreden met het resultaat. Na een software update van Apple werkte het programma niet meer. Dat is inmiddels snel en correct opgelost dus het programma werkt nu ook onder El Capitan.

Name: Jamie fox
Location: Dublin
Website: Foxpianotuning.com
Language: English English
Comment: I bought Dirk's piano tuner last year. I have been tuning pianos for twelve years and was never sold on a etd. Dirk's was recommended by a tuner friend who had had good results. I was shocked with the results. It really is as close to a good tuners ear as you can imagine. Very easy to use aswell. Makes pitch raising a treat. I had a problem with my laptop when I downloaded it. Dirk helped me through the process of installing the software. Great service.

Jamie fox
Dublin piano tuner
Foxpianotuning. com

Name: Bjorn Thienpont
Location: Roeselare (Belgium)
Language: Nederlands Nederlands
Comment: Beste Dirk,
Ik gebruik jouw tuner nu al een jaar of 4 en het is super!! Het wordt steeds verbeterd en het is super gebruiksvriendelijk. Als ik bij een klant vertrek zijn ze super tevreden over het resultaat. Ik twijfel er niet aan dat jouw ander stem-software van dezelfde kwaliteit zijn. chapeau!! Doe zo verder
Ps. Ook een pluim voor Ben Verbon!;) vele grtjs aan hem!


Name: Dirk Ettelt
Location: Traunwalchen, D
Language: Deutsch Deutsch
Comment: Die Software ist super. Ich hätte nicht gedacht dass dies wirklich so gut funktioniert. Heute gekauft und sofort meinen Flügel (Yamaha C2X) damit gestimmt - klingt hervorragend. Gebraucht habe ich etwa 2,5 Stunden. In den höheren Tonlagen wird das Stimmen allerdings etwas schwieriger, weil die Töne schneller ausklingen. Ein guter Signalpegel des Mikros ist hierbei zu empfehlen.

Die Software ist definitiv seinen Preis wert. Trotzdem war ich etwas enttäuscht über die letzte Preiserhöhung.

Name: Orlando Fleury
Location: 68400 Riedisheim France
Language: Deutsch Deutsch
Comment: Dirk's Project hat es mir ermöglicht mein Instrument (Grotrian Steinweg 1888) selber zu stimmen und dadurch auch besser zu kennen. Dieses geniale und einfache Klavierstimmprogramm ermöglicht es mir in die Dimension des Klavierstimmers einzutauchen und von Mal zu Mal werde ich in meinen Bewegungen und Handgriffen geschickter. Der Flügel ist danach perfekt gestimmt; ich habe das Gefühl einer vollendeten Verbindung zum Klang und zu dem alten Instrument. Ich stimme den Flügel wann immer notwendig und traue mich nun auch mechanische schwierigere Geschichten heran, wie an das Intonieren etc.

Das Design ist zwar etwas retro, das der 90er Jahre (beinahe wieder Kult....;) jedoch ist es absolut effizient.

Auf meinem Mac Book Air funktioniert alles bestens, sogar mit dem eingebautem Microfon!

Dirk ist immer erreichbar. Auch nach einem Jahr wurde mir nach einem Systemabsturz mit Softwareverlust sofort und unkompliziert mit einem neuen Download-link geholfen.
Dirk: thank you very much that you exist - you changed my life!

Name: Chris
Location: Los Angeles
Language: English English
Comment: I've used this software twice now to tune my piano, and the results have been great. The program is very easy to use. On top of that, I needed to transfer the program from an old computer to a new one, and immediately received assistance from Dirk on the process. Thank you!

Name: Boudewijn van Gelder
Location: West Lafayette, IN, USA
Language: English English
Comment: Wow, wow, wow!!! Dirk's Piano Tuner software and its results are just amazing. It took three days (about 16 hours in total) in August 2015 to tune the "family" piano (from about 1879, P. van Ooij, pianomaker and tuner, Haarlem, the Netherlands)... very carefully... step-by-step:
the piano had been tuned twice in the last 25 years. The last tuning dates back more than 15 years ago (in Nov / Dec 1999), and was done professionally. However, it was a "relative" tuning (with respect to the A4 that was well below 440Hz! ... the A4 had almost become a G#4, about 415Hz).
In those 16 hours, with the help of Dirk's Piano Tuner, I determined first the temperament and the optimal stretch that belongs to this piano. Subsequently, I brought the relative tuning up to an absolute tuning (as said, very carefully... in small incremental steps).
The piano produces now a sound as I hardly can remember it. The improvement of the quality of sound is, I think, mainly due the optimal temperament / stretch that may have never been determined so optimally (at least not in my lifetime of almost 68 years).
Dirk's Piano Tuner is a very well-designed tool that brings affordable tuning within reach of every piano owner / player.
A professional tuner would have had to come to our house may be four / five times (superseding easily the cost of Dirk's Piano Tuning software).


I recommend the software to anyone!


PS: Questions? My experience: support by Dirk is virtually instantaneous!

Location: Milano
Language: Italiano Italiano
Comment: Ho usato il programma dopo aver sostituito tutte le caviglie e le corde. Non potevo chiedere di meglio. Il risultato è tutto lì da ascoltare. La precisione è la vera potenza del programma.

Name: P van Geffen
Language: Nederlands Nederlands
Comment: Mooi ! al diverse keren heb ik tuner program gebruikt.
dan weer windows x nu windows 8.
geweldige service

Name: Amir Chizari
Location: 22391 Hamburg
Website: hsp-bmm.com
Language: Deutsch Deutsch
Comment: Ein tolles Programm! Ich bin begeistert. Besten Dank.

Name: Stefano Pasetti
Location: Venezia
Language: Italiano Italiano
Comment: Ho acquistato il "Dirk's Piano Tuner" lo scorso anno per accordare il mio pianoforte, successivamente lo uso per controllare l' accordatura ed aggiustare qualche corda;
con l' aiuto del 'piano tuner' il lavoro è stato abbastanza facile, inoltre devo dire che il piano suona bene e non è mai stato così intonato.
Ringrazio Dirk per le risposte ai miei vari quesiti e all' assistenza rapida.


Name: KEV
Location: France
Language: Français Français
Comment: Un SAV de Qualité.
Petit mot concernant le "service après vente".
Après avoir eu un problème d'ordinateur et avoir perdu le logiciel. (Presque sans avoir eu le temps de l'exploiter).
J'ai eu très peur d'avoir fait un tel achat pour rien.
Il m'a fallu l'instant d'un E-mail et d'une réponse le lendemain même pour tout résoudre. Plus d'inquiétude.
J'ai réinstaller Dirk's Piano Tuner, et je n'ai plus qu'a trouver un moment de libre pour accorder mon Piano.
Merci Dirk.
Dépannage très satisfaisant.

Name: Ingensand
Location: Schweiz
Language: Deutsch Deutsch
Comment: Der Pianotuner ist hervorragend. Die Software ist einfach zu installieren und zu bedienen und die Unterstützung durch die grosse Frequenzdifferenzanzeige beim Tuning ist vorbildlich. Bei Fragen und Problemen reagiert Dirk innerhalb von einem Tag.
Mein 160-jähriger Blüthner Flügel war nach dem Tuning mit Spreizung nicht mehr wiederzuerkennen. Er hat jetzt den phantastischen Klang, den man von alten Blüthnerflügeln erwartet.

Ich kann den Piano-Tuner und die gute Unterstützung durch Dirk sehr empfehlen

H. Ingensand

Name: Tom Gaskin
Location: USA
Language: English English
Comment: Great software. Easy to use. The results are better than the aural tunings I've done and even the professional tunings I've paid for, and after several tunings the software has paid for itself. I had a couple technical difficulties, but each time Dirk responded almost immediately by email and solved them. Great service! I'd recommend this product to anyone.

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