System and method for tuning an instrument to a meantone temperament

The meantone temperer external device is used in conjunction with a keyboard or other musical instrument. The meantone temperer is used to temper the connected musical instrument to any desired meantone-tempered scale, which is selected by the user. This device is operated by simply entering the desired temperament on the input keypad and pressing the "temper" button. Calculations are then made and the results are stored in RAM. When the user strikes a note on the musical instrument, a value is pulled out of RAM corresponding to the note struck. This value is then multiplied by the corresponding octave multiplier in ROM and the tempered note is sounded.

FIELD OF THE INVENTION 
The present invention relates to tuning a musical instrument and more 
particularly to tuning a musical instrument in accordance with the 
meantone of such an instrument. 
BACKGROUND OF THE INVENTION 
Musical instruments are tuned in a variety of manners. For example, a 
typical tuning for an instrument is through an equal temperament 
arrangement in which each of the notes in a particular device is equally 
spaced apart in frequency. 
Another type of tuning is tuning in accordance with the meantone scale. 
This type of tuning has been utilized typically to precisely tune a 
particular instrument to a particular type of user. Hence, for example, 
many of the great classical composers' music are played utilizing 
instruments that have been tuned in accordance with the meantone 
temperament to provide music which is precisely tuned to the particular 
music being played. 
Typically such meantone tuning is accomplished, for example, in a wind 
instrument, such as a flute or the like, by drilling holes in precise 
spots within the wind instrument to provide the proper tonal quality. In 
another example, a piano would be tuned by providing specific adjustments 
to the piano for the particular song or set of songs being played. Up 
until the present time, to provide this type of tuning required physical 
modification of the particular instrument to ensure that particular 
instrument has the proper tonal qualities. 
For electronic devices such as a MIDI device and the like, this meantone 
tempering has heretofore not been utilized because of the physical 
modification required of such devices. Accordingly, what has been 
typically done is to tune many devices and the like utilizing an equal 
temperament, thereby not ensuring the tonal quality that be obtained 
utilizing a mean tone temperament type device. 
Accordingly, what is needed is a system for allowing for electronic musical 
devices to be tuned in accordance with meantone temperament arrangements. 
The system should be simple and easily adaptable to such systems and 
should be cost effective. The present invention addresses such a need. 
SUMMARY OF THE INVENTION 
A system for tuning an instrument to a meantone temperament comprising an 
input key pad for providing a desired meantone temperament; a computation 
means for receiving the desired temperament and for providing exploded 
digital data representative of a cycles per second of the desired meantone 
temperament; a memory means for receiving the exploded data from the 
computation means; and a processing unit coupled to the memory means and 
the instruments for processing, relaying and routing data to and from the 
musical instrument.

DESCRIPTION OF THE INVENTION 
The present invention relates to an improvement in tuning a musical 
instrument. The following description is presented to enable one of 
ordinary skill in the art to make and use the invention and is provided in 
the context of a patent application and its requirements. Various 
modifications to the preferred embodiment will be readily apparent to 
those skilled in the art and the generic principles herein may be applied 
to other embodiments. Thus, the present invention is not intended to be 
limited to the embodiment shown but is to be accorded the widest scope 
consistent with the principles and features described herein. 
The meantone temperer external MIDI device is used in conjunction with a 
MIDI keyboard or other MIDI musical instrument. The meantone temperer is 
used to temper the connected musical instrument to a desired 
meantone-tempered scale, which is selected by the user. This device is 
operated by simply entering the desired temperament on the input keyboard 
and pressing the "temper" button. Calculations are then made and the 
results are stored in RAM. When the user strikes a note on the musical 
instrument, a value is pulled out of RAM corresponding to the note struck. 
This value is then multiplied by the octave multiplier in ROM and the 
tempered note is sounded. This is all done using MIDI messages within a 
fraction of a second. 
The use of the meantone temperer will benefit the user in a number of ways: 
1. Users can very quickly change from one temperament to another. This will 
allow the user to eliminate the wasting of expensive studio time and will 
also create a delay-free performance when using the meantone temperer 
during a live show. 
2. Users can experiment with different intonations. 
3. Users will be able to hear classical compositions exactly as they 
sounded when the composer wrote them. Since the meantone temperer is a 
MIDI device, it can be used along with other MIDI devices in a network. 
Referring now to FIG. 1, what is seen is a meantone temperer 10 in 
accordance with the present invention that can be utilized in conjunction 
with a MIDI device 50. The meantone temperament system 10 includes an 
input keypad system 12 which is coupled to a meantone computation system 
14. The computation system 14 in turn is coupled to a first memory 16 
which receives exploded computations from the computation system 14. The 
first memory 16 is coupled to a second memory 18 for multiplexing the 
octave level of the exploded computations. The meantone temperer 10 also 
includes a MIDI processing unit 20 which receives tonal signals from the 
MIDI device 50. The processing unit 20 sends and receives data from the 
first and second memory. Each of these components will be described in 
more detail hereinbelow. 
Input Keypad 12 
The input keypad includes two components, a temperament component 13 and a 
normalizer component 15. The temperament component is one in which the 
desired temperament is entered. This desired temperament can be entered in 
a variety of ways. Then the correct pitch is entered by a normalizer. This 
pitch can be provided in a variety of ways. Next, these two inputs are 
then used to compute the proper meantone temperament. Both of these inputs 
can optionally be viewed on the output LCD 30. 
Computation System 14 
The computation system 14 receives the inputs from the input keypad 12 to 
compute the proper meantone temperament for the device 50. Referring now 
to FIG. 2, what is shown is a flow chart of the operation of the 
computation system 14. Accordingly, as is seen, initially a fifth value is 
computed via step 142. The value is then utilized to compute the 
appropriate cent value, via step 144. The cent value for each scale degree 
are computed in accordance with a meantone temperament procedure. 
To more particularly describe such a procedure, refer to the following 
discussion which explains the proper procedure for finding the thirteen 
chromatic notes of a given meantone-tempered scale. Starting with a circle 
root (CRT), the cent value of the tempered fifth (f) is added to the value 
of CRT, which yields the value of one of the notes in the desired 
(user-selected) meantone scale. Then, f is added to this sum (CRT+f), 
which yields the value of another note in the desired meantone scale. 
Then, f is added once again to this new sum (CRT+f+f), which yields yet 
another note in the desired meantone scale. This cyclic addition procedure 
is used for the desired (user-selected "cyclic steps upwards." Counting 
the addition of f to the initial CRT as the first step, this addition 
procedure is carried out (cycled) for the amount of user-selected "cyclic 
steps upwards." 
This same basic procedure is performed again, although this time 
subtracting the tempered fifth (f) cyclically from the initial circle root 
(CRT). This time, however, it is repeated in order to carry out the 
user-selected "steps downwards." After this downward (subtraction) process 
is completed, the note values obtained from both the addition process and 
the subtraction process will equal thirteen notes (number of notes in a 
chromatic scale). The first twelve of these thirteen note values (C to B) 
are the values used by the meantone temperament system to temper the 
connected musical instrument. 
Thereafter, a ratio is computed from the cent values, via step 146. 
Finally, the cycles per second are computed from the ratio, via step 148. 
This cycle per second information is utilized to determine the meantone 
temperament of the particular song to be played. To convert this cycle per 
second frequency into a unit that can be digitally utilized an explode is 
required such that the tempered base frequencies are separated into whole 
number units, via step 150. 
For example, if the cycle per second is 100.265 cps, then the exploded 
cycle per second to be utilized in digital format would require 100 to be 
sent first in one memory location, next the 2 which represents two tenths 
in a second memory location, next the 6 which represents six 
one-hundredths in a third memory location, and 5 which represents five 
one-thousandths in the fourth memory location. This separation is 
necessary because only integers not factors can be stored in the location. 
More importantly, the digital values are necessary in order to provide the 
proper tonal information to MIDI device. 
RAM 16 
First memory or RAM 16 comprises a plurality of bytes, typically, in a 
preferred embodiment in the case of a piano, 352 bytes, four bytes for 
each piano key. The RAM 16 receives the stored tempered base frequencies 
in exploded form. 
ROM 18 
ROM 18 second memory or ROM 18, consists of eighty-eight bytes, one for 
each piano key. The ROM 18 is used to store octave multipliers, and the 
octave multipliers are used in turn to multiply the notes from RAM 16 by a 
particular octave. 
MIDI Processing Unit 20 
The function of the processing unit 20 is to process, relay and route 
information to and from the MIDI Device 50 and to and from other connected 
musical devices. 
Accordingly, the present invention operates in the following manner: 
By entering desired temperament and normalizer on the input keypad and 
pressing the temper button, calculations are then made by the computation 
means system and the results are stored in the RAM. When the user strikes 
a note on the musical instrument, a value is pulled out of the RAM 
corresponding to the note struck by the info processing unit. This value 
is then multiplied by the octave multiplier in ROM and the tempered note 
is sounded. Through the operation of the present invention, a user can 
quickly change from one temperament to another. 
The present invention can be utilized in a variety of instruments and is 
not limited to a MIDI device. Referring now to FIG. 3, another embodiment 
of a meantone temperament system 100 for telescoping organ pipes is used 
to temper a pipe organ 300 to a desired meantone-tempered scale, which is 
selected by the user. The system 100 is powered by a power supply 154 
which is activated by a switcher 156 (key operated) in this embodiment. In 
a preferred embodiment, the system would include a power outage/premature 
shutoff protector 158. This system 100 is operated by simply entering the 
desired temperament on the input keypad 113 and pressing the "temper" 
button similar to that shown in FIG. 1. Calculations are then made in 
computation system 102 and the results are stored in RAM 104. These values 
are then sent to gearboxes 106 connected to each set of organ pipes 108 in 
order to determine how many seconds the gears are to rotate in order to 
telescope the pipe extensions 110 to the correct settings. When all the 
extensions 110 are telescoped, the user may play the organ 300 which will 
reflect the new temperament. Because of the analogue movements, the user 
must wait a little while longer when using the meantone temperer 100 for a 
pipe organ 300 than when using a MIDI musical instrument as described in 
relationship to FIG. 1. However, this short wait comes only during the 
initial mechanical movement of the pipe extensions 110 via data 
transmission unit 120. When temperament is finished, the organ 300 will 
play exactly as before; only the lengths of the pipes have been altered. 
Accordingly, the use of the meantone temperer will benefit the user in a 
number of ways: 
1. Users can very quickly change from one temperament to another without 
interrupting or delaying a concert or church service. This will also 
eliminate the wasting of expensive studio time when making full pipe organ 
recordings. 
2. Users can experiment with different intonations. 
3. Users will be able to hear classical compositions exactly as they 
sounded when the composer wrote them. 
The meantone temperer telescoping organ pipes system requires virtually no 
cosmetic alteration to the existing layout of the church or cathedral in 
which it will be used. Cosmetic alterations would be necessary only if the 
church or cathedral has pipes that are visible from the sanctuary; even 
then this alteration would be virtually unnoticeable. This should be a 
very positive point when selling this system to a prospective buyer. 
Accordingly, the present invention provides for tuning an instrument in 
accordance with a meantone. The system can be utilized with a variety of 
instruments and can adaptably adjust the tuning of the instrument in 
accordance with a particular meantone reliably and easily. 
Although the present invention has been described in accordance with the 
embodiments shown, one of ordinary skill in the art will readily recognize 
that there could be variations to the embodiments and those variations 
would be within the spirit and scope of the present invention. 
Accordingly, many modifications may be made by one of ordinary skill in 
the art without departing from the spirit and scope of the appended 
claims.