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CHAPTER 4-1 CHAPTER FOUR TUNING THE REMAINING "75" The temperament has been set and we must now proceed to tune the rest of the piano by tuning BEATLESS OCTAVES. On the surface, it seems that octave tuning will be relatively simple compared to setting the temperament, since our goal is to just tune all octaves up and down beatless. This is true up to a point, and that point begins for most of us when we get above D-54 or below C-28. There are numerous reasons for this problem, and the situation varies from one piano to another. When you reach the point in the treble or bass where you are hearing harsh or false sounds, you must rely on certain tests to ensure the octave is properly tuned. There are many tests available and tuners must understand and use them on every tuning. Do NOT rely solely on the octave interval. You will find this insufficient. Please read this entire chapter before beginning prac- tice. MUTE ENTIRE PIANO I recommend you mute the entire piano as a first step for all tunings. This is simply to use your muting strips and individual mutes to mute off all but one string of a note. The previous explanations on how to use the mutes should be sufficient except for possibly a couple of points. The top note (C-88) usually cannot be muted off in the same way as the other three string notes. You will have to place a mute between the left and center string or the right and center string. Also, on the other ends of the middle and treble sections (on some pianos) you may have to do the same. Pianos are strung differently, so there is no one way to mute a piano that will work for all. The important thing to remember is that only ONE string per note should sound when a key is struck. When you are tuning a note that is muted off differently, be aware of which tuning pin you are turning. It is easy to place your hammer on a muted off string out of habit and turn it until the string breaks. If you ever turn a tuning pin and hear no difference in the sound, always check to see if you are on the right pin. I usually use two muting strips to mute off the treble and tenor sections (three string sections) and individual mutes for the ends of these sections and the bass. The correct way to insert the muting strip is to use either the end of a wire rubber mute or a screwdriver to push the felt CHAPTER 4-2 between the strings. Make sure you make the fold high enough so the middle string is not muted. The only problem you may have is in using the muting strip on the lower part of the extreme upper section. The dampers must be pulled back and the strip inserted between them and the strings. Push on the right (sustain) pedal and also help with your hands to accomplish this. Care must be taken to not tear off any damper felt. After you have muted the entire piano, play each note and ensure that only one string is sounding and you have not somehow muted off all strings of a unison by not making the loops in the muting strip high enough. Now, you can proceed to tune the remainder of the piano by tuning beatless octaves. The first octave to tune is C#-41 to C#-29. Then tune all octaves up until you reach C-52. Then tune all the notes from B-27 to the bottom of the piano. Return to C#-53 and tune up the entire scale. Keep in mind that since the temperament was set from C-28 to C-40, When you tune octaves up and down the piano you are automatically adjusting the temperament by tuning BEATLESS OCTAVES - C# to C#, D to D, D# to D# and so forth up and down. If this still sounds confusing, review the beginning chapters once again. I will now present numerous octave tests and you will have the opportunity to decide which ones appeal to you and serve you best. ONE WORD OF CAUTION! Don't bog yourself down by using more tests than necessary. You may find a normal 90 minute tuning turning into over two hours very quickly. Tests are necessary and must be used, but try to find a happy medium between too few and too many. It will come WITH TIME - With Time - with time... TESTS WITHIN THE OCTAVE BEING TUNED Refer to Appendix A while studying the following examples. A) When tuning B-27 from B-39, you can compare the beat rates of the MAJOR THIRD G-35 to B-39 and the minor sixth B-27 to G-35. They should be the same. B) The minor third B-27 to D-30 will beat the same as the MAJOR SIXTH D-30 to B-39. Also, the FOURTH/FIFTH test explained previously is very helpful between F-33 and C-52. This test requires that in any octave, a perfect fifth above a perfect fourth will beat the same as the fourth. EXAMPLE: C-28 to F-33 (a perfect fourth) will beat the same as F-33 to C-40 (a per- fect fifth). CHAPTER 4-3 The tests described so far can be used in any octave, but unfortunately they become increasingly less useful when reaching the high treble and the low bass. The FOURTH/FIFTH test is usually effective above F-33 and below C-52. This will vary from piano to piano. The minor third/MAJOR SIXTH test described above is useful between C-16 and C-64. When tuning DOWNWARD, if the minor third beats FASTER than the MAJOR 6th, the lower note of the octave is sharp. If the minor third beats SLOWER than the MAJOR 6th, the lower note is flat. Conversely, when tuning UPWARDS, if the MAJOR 6th beats faster than the minor 3rd, the upper tone of the octave is sharp. If it beats slower, the upper tone will be flat. In other words, the two intervals should have the SAME BEAT RATE. TESTS EXTENDING BEYOND THE OCTAVE BEING TUNED MAJOR THIRD/TENTH TEST A very good test in tuning up to C-64 is the MAJOR THIRD/TENTH TEST. For example, if you are tuning G-35 from G-47, the interval from D#-31 up to G-35 will beat the same as the interval (tenth) D#-31 up to G-47. IF the tenth beats faster than the MAJOR THIRD, the upper note of the octave is sharp. On the other hand, if the tenth beats slower than the MAJOR THIRD, the upper note of the octave is FLAT. This test is similar to the minor third/MAJOR SIXTH test in that the beats of the intervals are alike. This test is useful when tuning downwards by ensuring that the beats of the descending tenths become SLOWER as you proceed towards the bottom of the piano. USING DOUBLE OCTAVES When tuning in the upper treble it is useful to check your upper note by comparing it with the note two octaves below. OCTAVE TENTH TEST When tuning the high treble, another useful test inter- val is the OCTAVE/TENTH. This is simply the tenth extended by an octave. This test is applied in exactly the same way as the MAJOR THIRD/TENTH test. EXAMPLE: When tuning C-64 to C-52 you would compare the beat rates of G#-36 and C-40 with the beat rates of G#-36 and C-64. They should beat the same, in this case, approximately 8 C.P.S. This test is also useful in tuning the low bass in the same way as the MAJOR THIRD/TENTH test - by listening for gradually decreasing beat rates as you descend. CHAPTER 4-4 OCTAVE/MINOR SEVENTH TEST One more test to use in the extreme low bass is the OCTAVE/minor seventh test. EXAMPLES: C#-29 down to d#-7 = 5 beats per second A-25 down to B-3 = 4 beats per second G-23 down to A-1 = 3 1/2 beats per second TIPS TREBLE TUNING When tuning the upper treble, you must be aware of the fact that the tone will fade rapidly after the string is struck. It is sometimes necessary to strike the string repeatedly and loudly to overcome this problem. FALSE BEATS are prevalent in the treble beginning as low as D-54 and continuing upwards. Some pianos will have many, others very few. Refer to the section on false beats (below). The extreme upper treble can be tested by running two octave arpeggios up to the note being tuned in addition to the double or triple octave tests. BASS TUNING Elsewhere in this course we discussed the fact that the upper partials of a fundamental are not necessarily equally tempered, but the tuned piano IS. Therefore, since the upper partials of the low bass notes are low enough, they will clash with higher notes on the keyboard and WIll be heard. It is for this reason that we tune the low bass notes to the TEMPERED intervals of the TENTH (octave and a third) and the SEVENTEENTH (two octaves and a third). Also, the interval of a TWELFTH (octave and a fifth) can be used in the same way, although the twelfth will beat so slowly as to almost seen beatless. This makes it a good test to ensure you are not way off course. FALSE BEATS You have been taught to tune unisons and octaves beat- less and of course this is the goal. However, you will find that even though you have muted off all but one string of a unison, that one string will sometimes produce beats when struck. It may be the center string, or either of the two outer strings. CHAPTER 4-5 If you have ten piano technicians discussing the problem of false beats, you will probably have ten different solutions to the problem. Solving this problem is beyond the scope of this course, but coping with the problem is something you will have to do. False beats usually occur anywhere above C-52. When you are tuning a unison and one string of the unison beats when sounded alone, your only recourse is to tune the other strings of the unison so the least amount of beats are audible when the note is struck The higher the quality of the piano, usually the fewer false beats are present. However, I must say that as of now (1991) I have been tuning pianos for over 30 years and in can recall very few pianos that were completely free of false beats. One was a concert grand and the other surpris- ingly was a medium priced console. Causes for false beats are many, so I will only list a few of the most common. 1. A twist or kink put in the wire on stringing 2. Faulty bridges and/or bridge pins 3. Wire of uneven thickness 4. Rust on the strings 5. Poor scaling This is a problem you will live with throughout your tuning career. You now know how to detect false beats so you must learn to compensate as best you can. Just remember, if you are trying to tune a beatless unison, and you simply cannot stop the beats, check each string of the unison and see if a false beat is there. BASS STRINGS BUZZING Occasionally, you will find a definite buzz when tuning a bass string. This buzz is usually a result of improper installation or a break in the copper winding. Rather than immediately replacing the string, loosen the tension enough to slip the bottom of it off the hitch pin. Then twist the loop a full turn in the direction in which the winding points. Replace the string on the hitch pin and tune. If the buzz is still there and you can deter- mine that it is not coming from another source, you should replace the string. Follow the instructions in chapter six and remember to twist the bottom of the string as described above before tuning. It will save having to do it a year or two later. CHAPTER 4-6 In this chapter, you learned: 1. How to mute the entire piano 2. Tuning tests to use within the octave being tuned 3. MAJOR THIRD/TENTH TEST 4. Double octave test 5. Octave tenth test 6. Octave/minor seventh test 7. Important tips on treble tuning 8. Definition of "False Beats" 9. Why bass strings sometimes "buzz" & how to stop it Press P to print out this chapter, or ESC for the menu