The HOHNER Harmonica Tuner was developed by Dirk's Projects
in collaboration with Hohner Musical Instruments and is designed to enable
harmonica owners to tune their own instruments.
The tuning process is easy to learn and is clearly explained
in the tutorial video.
The tuner software can tune not only single reeds, but also
double reeds tuned in tremolo. This unique feature enables one to set the
desired beats easily and accurately. Beats are very hard to tune when tuning
both reeds separately from one another. With this tuner, both reeds can be
measured simultaneously, together with the sounding beats, making it very easy
to tune the beats.
The current version of the software supports equal
temperament only. Future versions will support additional temperaments as well
as additional languages. New features like these will be announced through the
news letter. Subscribe to the news letter on the website:
(Click on the "News" button)
Table of contents
to tune a harmonica
number of important terms
and placement of the microphone.
the tuner for the first time
tuning process with the HOHNER Harmonica Tuner
accuracy of the tuner
A harmonica is tuned by filing or scraping small amounts of
material from the reeds that need adjusting. A reed's pitch can be tuned up or
down using special tools. The images below show the HOHNER toolset that is used
to tune a harmonica.
For a detailed explanation of the tuning process, see the
tutorial video on the website.
The trial version is meant to help you get a good idea of
the possibilities offered by the tuner. The trial version can be used to tune
all the reeds of your harmonica. Some features are only available in the full
version, like tuning the beats of tremolo reeds and using the tuner in full screen
The trial version needs to be activated each time it is
started. It therefore needs an Internet connection. The full version does not
need to be activated each time; it does not need an Internet connection.
The full version can be purchased on the website: http://www.dirksprojects.nl
The tuner can be extended with modules. These extension
modules add extra functionality. At this moment there are no extension modules
available yet. Check the Internet site for new extension modules: http://www.dirksprojects.nl
the number of waves per second of a tone (pitch).
the total range of wavelengths that can be perceived by the human ear.
sound with a fixed pitch.
notation indicating a tone with a specific pitch and length.
ascending or descending sequence of tones with a fixed pattern of intervals.
the perceived frequency of a tone. This is the fundamental frequency.
tone or tonic
the perceived pitch. The lowest tone of the collection of tones that make up a
partial tone in a sound, with a higher frequency which is a multiple of the
interference beats heard when two tones with a small difference in pitch sound
at the same time.
The difference in pitch between two tones, measured in semitones.
the smallest musical interval in western music. An octave consists of twelve
semitones. In equal temperament all semitones are evenly divided in frequency,
so that an octave is divided into 12 equal steps. On a piano the interval
between any two adjacent keys, whether white or black, is always one semitone.
The addition of a sharp (#) or flat (b) sign always changes the interval by one
semitone (for example C to C#).
the interval between two tones where the second tone has twice the frequency of
1 Octave = 12 Semitones.
• Tuning or
the way in which the individual frequency values for the specific tones on an
instrument are selected. In Western music, equal temperament (12TET) is the
most popular. Other temperaments include: just intonation, the Pythagorean
tuning, mean tone temperament and the 31 tone equal temperament.
a chromatic scale is a scale that contains all twelve semitones within an
c – c# – d – d# – e – f – f# – g – g#
– a – a# – b (the white and black keys of a piano)
A whole tone
is always equal to two semitones, wherever it may be found on an instrument.
a scale with a fixed sequence of intervals. Every major scale uses the interval
sequence 2 - 2 – 1 – 2 – 2 – 2 – 1, e.g. the C major scale C – D – E – F – G –
A – B - C (the white keys on the piano keyboard). The relative minor scale A
minor uses the same notes, but begins and ends on A, giving the interval
sequence 2 – 1 – 2 – 2 – 1 – 2 – 2: A – B – C – D – E – F – G - A
unit for frequency.
1 Hz = 1 wave per second.
logarithmic unit for the difference in pitch with respect to a tone in the scale.
1200 Cent = 1 Octave.
100 Cent = the distance between 2 successive semitones in an equal temperament.
all frequencies that occur in a sound. The frequency spectrum can be presented
in the form of a graph.
The accuracy of the microphone
For the tuner, only the frequency of the measured sound is
important. The volume does not matter. The sensitivity of the microphone is
therefore not important. The accuracy of the measured frequency is. This is
however easily sufficient in any microphone.
Externally connected or built in
A built in microphone, such as those found in most laptops,
is not always suitable. It picks up more background noise than an external
microphone connected to the sound card. The housing of the laptop picks up
sounds and vibrations and passes them on to the microphone. The cooling fan of
the laptop is an important source of extraneous noise. A built in microphone is
also often not able to measure the lowest frequencies. Another disadvantage of
the built in microphone is that it is impossible (or difficult) to position it
optimally in relation to the instrument. An external microphone, which is
connected to the sound card with a cable, can simply be placed in the desired
The distance from the microphone to the instrument
The closer the microphone is placed to the instrument, the
smaller the influence of the background noise in relation to the sound of the
instrument. A shorter distance will improve measurement accuracy.
Any digital effects present need to be disabled before
tuning, as they can otherwise falsify the measurement results. Microphone
settings such as 'boost', 'sensitivity', 'volume', 'gain' and 'balance' are of
no consequence here.
An external microphone with a cable connection to the
computer is the preferred configuration, because it can be easily placed in a
suitable location. This means that a simple microphone connected to your
computer's soundcard will suffice. The frequency range of many cheap
microphones is often not known. A high quality dynamic microphone will give
better results, especially in the lower frequencies. Generally speaking, a USB
microphone will too. In that case, the internal sound card of the computer is
not used, which can be an advantage. The much more expensive condenser
microphones are perfectly usable, but they won't give you a better tuning
result. At all times, digital effects in the microphone software have to be
Using the tuner for the first time
Hovering the mouse-cursor above a button or a window will
show a "tool tip". A tool tip is a small text box with explanation
about that particular button or window.
Select the sound input
To be able to use the tuner it is necessary to select and
configure the desired sound input channel. Generally this will be a microphone.
When you start up the tuner for the first time the configuration screen is
The left part of the configuration screen above is important
for selecting and configuring the sound input. At 'select the recording device'
you select the sound card. The different sound inputs of the selected sound
card are enumerated at 'select the sound input in the recording device'. Here
you select the sound input to use.
The resulting signal from the selected input is shown in the
graph at the bottom. The tuner works best when the input signal is as strong as
possible, but it should stay clear of the top and the bottom of the graph to
avoid distortion. The strength of the signal can be controlled by moving the
'Sensitivity' slider. When a microphone is selected and its signal is too weak,
the check mark 'Microphone boost' can be set to amplify the signal more.
If the stereo input has a "Balance Slider", it
should be set in the middle.
The button 'Windows Recording Control for the selected
device' opens the sound input configuration screen of Windows. This screen is
normally not necessary.
Sometimes a hum (50 or 60 Hz) is audible on the input. This
is generally caused by either bad earthing or a poor power supply. It can be
taken out by checking one of the hum filter boxes.
Not using these filters can result in unwanted detection of
certain tones, e.g. G1 (49Hz), A#1 (58,27Hz) or B1 (61,74Hz).
Automatic pitch detection
The HOHNER Harmonica Tuner automatically detects the pitch
of the sounding tone. The detected tone will be displayed in the Tone Name
Window. Once the detected tone is stable the word "Lock" will appear.
Now the detected tone will not change to another one anymore. After a few
seconds of silence the next tone can be tuned.
Tuning with the HOHNER Harmonica Tuner
up the Hohner Harmonica Tuner on your computer. Then connect and set up the
microphone. It's recommended to place the microphone on a rubber pad or a
cushion, so it won't pick up vibrations from the floor.
your screen, check in the upper left corner if the right microphone input is
a quiet environment with minimal ambient noise. In particular, continuous,
monotonous sounds, such as the sound of a fan or an aquarium pump, will make
accurate measurement more difficult.
the button "Reeds" to specify if you are tuning a single reed or a
tremolo reed pair. If 2 reeds are sounding simultaneously, the number of reeds
must be set to 2. If only 1 reed is sounding, the number of reeds must be set
you can begin the actual process of tuning your harmonica. Play the reed you
want to tune and observe the red needle in the bottom part of the window. When
measuring the pitch of a reed, it is essential to play with an open and relaxed
jaw and throat position, while maintaining a constant but gentle airflow. If
you fail to do this it is very difficult to obtain an accurate measurement, as
the throat shape and air pressure can slow down the frequency with which the
reed oscillates and so falsifies your reading. Varying your air pressure and
throat shape will also make it hard to produce a stable pitch in the first
place. Be gentle. When the needle gives a stable reading on zero, the reed is
in tune. In practice, a reed can never be tuned perfectly, but this is not
really necessary, as the human ear usually doesn't detect small deviations in
Please also bear the following in mind: The scale behind the needle is
calibrated in cents. 100 cents at pitch B1 is equivalent to only 3.57 Hertz.
100 cents at pitch C8, however, is equivalent to 241.92 Hz. This is why higher
tones need to be tuned more accurately (expressed in cents) than lower tones.
C8 should not deviate more than 0.1 cents, but B1 may deviate by up to 3 cents.
the pitch is too low, file a little material from the upper surface of the reed
at the tip. If the pitch is too high, scrape a little material from the base of
the reed in front of the rivet pad. Proceed with care and exert as little pressure
as possible in order to avoid inadvertently changing the offset and alignment
of the reed. Before attempting to tune your harmonica, please carefully study
the detailed instructions shown in the tutorial video on the website first.
tuning, all reeds on your harmonica should be in tune and ready to be played.
However, don't forget that even with the HOHNER Harmonica Tuner, you still have
to develop a feeling for handling the tuning tools and also learn to breathe
properly while measuring the pitch in order to achieve a completely
satisfactory result. Tuning accurately requires experience, so patience is
necessary. Due to a number of factors, the pitch of a reed may change following
the tuning process and require readjustment. With single reed instruments, we recommend
always checking that intervals such as octaves sound without interference
beats. The HOHNER Harmonica Tuner is an invaluable tuning aid, but your own ear
is the final judge.
The input signal
The sound signal the tuner uses for its measurements is shown
in waveform at the top of the tuner window. The height of the wave indicates
the strength of the input sound. If the sound becomes too strong for the wave
to fit the window, it will be scaled down. The name of the sound input that is
chosen in the settings screen (Menu - Tuner Settings) is also shown in this
window. In this window you can check if the input signal is present.
The detected tone
The detected tone is shown as a character with an octave
number and if applicable a sharp sign in the tone window of the tuner (bottom
right). The frequency of the A4 is shown in the top left corner above this
character. Once the detected tone is stable the word "Lock" will
appear. Now the detected tone will not change to another one anymore. After a
few seconds of silence the next tone can be tuned.
The frequency spectrum of the detected tone
The frequency spectrum of the detected tone is displayed
graphically in the frequency spectrum window. The horizontal axis represents
the frequency and vertical axis represents the amplitude. A sounding reed
causes a peak in the frequency spectrum and the red waveform represents the
frequency spectrum of the detected tone. The tuner detects the peak in the red
line and marks it with a blue vertical line. The vertical grey line indicates
the desired frequency of the detected tone.
The deviation of the reed's frequency
The reed's deviation from the target frequency is shown
numerically in window "Cent 1" and is also represented by a moving
red needle (bottom part of the window). In "2 reeds" mode, the
deviation of the second reed is shown in window "Cent 2" and is
represented by a second red needle. The two sounding reeds produce beats which
are shown in the window "Beating".
When tuning the two reeds of a tremolo reeds pair, always
tune the first reed using window "Cent 1" or the red needle. When
tuning the second reed, always use window "Beating". This is the only
way to tune the beats accurately! Never use window "Cent 2" or the
second red needle.
The desired beats
Every tremolo reed pair needs to beat at a specific speed.
The lower tones need different beats than the higher tones. You can specify the
desired amount of beats in the tuner settings screen: Menu - Tuner Settings.
The desired beats for the detected tone are shown in window
"Desired". When tuning the second tremolo reed, try to equate the
measured beats (window "Beating") to the desired beats (window
The A4 frequency
The A4 frequency used by the tuner can be set in the
settings screen: Menu - Tuner Settings. All other tones are adjusted
Freeze the tuner
The movement of the tuner needle, numbers and graphs can be
stopped, to enable easier reading. Just click the "Freeze" button.
Hitting the spacebar will do the same.
Enlarge the tuner to a full screen
To get full visual access to the tuner window, enlarge the
window clicking the square box, top right of the window (see below). This is
especially helpful when your screen is positioned at a distance.
The maximum accuracy in Hertz and in Cent
The accuracy of the tuner is better (less) than 0.1 Hertz
(waves longer than 10 seconds). The accuracy in Cent gradually changes over the
range of the tuner because a Cent is a relative unit. The interval between two
successive semitones in Hertz increases as the pitch gets higher while the
interval in Cent is by definition always 100. Some values of the accuracy of
the tuner in Cent: C1: 5.2 Cent, C2: 2.6 Cent, C3: 1.4 Cent, C4: 0.6 Cent, C5:
0.4 Cent, C6: 0.16 Cent, C7: 0.08 Cent, C8: 0.04 Cent. So in Cent, the tuner
gets therefore more accurate as the pitch gets higher.
Detectable pitch differences
The smallest pitch difference detectable by the human ear is
approximately 2 Hertz. The accuracy of the tuner of ±0.1 Hertz is of a
different order of magnitude. This high degree of accuracy is necessary to
measure the beatings between two reeds. A change in pitch difference of more
than approximately 0.1 Hertz causes a noticeable change in the speed of the
The tuner uses the sound card for its measurements. To
compensate possible errors in the sound card, the tuner carries out an
automatic calibration. Manual calibration such as those often possible on
conventional tuners (with a screw for example), is not necessary. Because of
this the measurements of the tuner are always accurate.
The internal accuracy
The tuner shows the measured errors to 1 or 2 decimal places
(digits after the decimal point). Internally, the tuner calculates to 7 decimal
places. Immediately before a deviation is shown, the figure is rounded off to 1
or 2 decimal places.
The HOHNER Harmonica Tuner runs optimally on machines
starting from Pentium II, 1 GHz. On less fast machines the tuner also works
fine, but will react more slowly. It will run on Windows 2000, XP, Vista and 7 and uses a microphone input.