tunelab_pro_manual

TuneLab Pro 1. What is TuneLab Pro? 1 - basics and definitions of terms used in later chapters. 2. Normal Tuning Procedure 11 - how to tune your first piano with TuneLab. 3. All About Offsets 17 - five different kinds of cents offsets used by TuneLab. 4. Over-pull (Pitch-Raise) Tuning Procedure 19 - how to make a pitch raise more accurate. 5. Calibration Procedure 23 - something you need to do only once when TuneLab is first installed. 6. Special Functions 27 - split-scale tuning for spinets, tuning exam mode, making temperament files, measuring voicing and sustain time, aural sequences 7. Advanced Custom Settings 33 - TuneLabSettings.txt options: keeping the Basic Offset and showing an alternate interval in tuning curve adjuster, etc. 8. Menu Items and Options 35 - a complete listing of menus and options. © 2008 Real-Time Specialties (734) 434-2412 www.tunelab-world.com 1 What is TuneLab Pro ? TuneLab is software that helps you to tune pianos. This software comes in various forms - TuneLab Pro (for Windows laptops), TuneLab Pocket (for the Pocket PC), and TuneLab for Smartphones (for Windows Mobile Smartphones). Although these platforms are quite different, most of the features of TuneLab are implemented similarly in all versions. This manual describes TuneLab Pro. There are separate manuals to describe TuneLab Pocket and TuneLab for Smartphones. Visual Tuning TuneLab is one of the class of devices or software programs called “Visual Tuning Aids” or “Electronic Tuning Devices”. These are devices or programs that provide a piano tuner with real-time guidance during tuning. The sound of a note as it is played is picked up by a microphone and analyzed. The results of the analysis are displayed in a visual pattern. In the case of TuneLab, there are two main visual patterns that are displayed - the phase display and the spectrum display. Both of these displays indicate if the pitch of a note should be raised or lowered, but each display has its own unique advantages. Having both displays visible simultaneously gives the piano tuner the best of both worlds. Phase Display The phase display is the horizontal band shown above. This display is used for fine tuning. The black squares move to the left if the note is flat and to the right if the note is sharp. The closer you get to the correct tuning, the slower the black squares will move. The goal is to make the black squares come as much to a stop as possible. If the piano string has any false beats then the black squares may appear to move in an irregular fashion, sometimes moving back and forth. When there is no note playing, or when the note being played is far from the correct pitch, the black squares will disappear or move randomly. This display is called a phase display because it displays the phase of the sound from the microphone as compared to the phase of an internally generated reference pitch. The movement of the squares can be compared to listening to beats between a tuning fork and a note on the piano. For the bass and midrange, when a square makes one complete trip around the display, that corresponds to one complete beat that you would hear when comparing two tones. For higher notes the display is artificially slowed down in order to keep the speed of the display in a reasonable range. Chapter 1 2 Spectrum Display The spectrum display is the graph shown above zoomed-in to ±130 cents around the desired pitch. Using the Edit Options menu, you can choose to make the traces thicker (as shown) for easier visibility, at the cost of a slight loss of resolution. This display shows how the sound energy is distributed across the frequency spectrum. If TuneLab is listening to a pure tone, then the spectrum graph will show a single peak. The example seen here was made from a A-440 tuning fork that was actually a little flat. The red line in the center of the display marks the correct pitch. The green lines nearest the center mark the points that are 10 cents above and below the correct pitch. The green lines far from the center mark the points that are 100 cents above and below the correct pitch, i.e. the previous note and the next note. The object in tuning with the spectrum display is to tune the note until the peak of the graph is centered on the red line. The spectrum display has several advantages over the phase display. One is that it shows where the pitch of the piano is, even when that pitch is far from the correct pitch. The other advantage is that the spectrum display can show several peaks at once. This is what you would get when playing a poorly tuned unison: Here the piano note C7 is being played with one string tuned nine cents higher than the other two strings. By looking at individual peaks it is possible to tune notes in the high treble without mutes! You simply tune one of the strings and watch which peak moves. You can move that peak to the red line and then that string will be at the correct pitch. However, tuning this way is not as accurate as tuning by sounding one string at a time, because the multiple peaks tend to become blurred as they merge into one another. The Spectrum Display can also be zoomed in on the center ±10 cents in the center, while still showing ±130 cents or ±260 cents overall. When one of these “dual-zoom” modes is selected, the numbers at the bottom show offsets in cents rather than frequencies in Hz. Here is one such setting of the Spectrum Display showing two simultaneous notes - one at A6 and the other at A#6 (+100 cents higher than the target pitch): 3 As shown in the upper right corner of the previous Spectrum display, if a tone is recognized close enough to the target pitch, then there will be a numerical display of the tuning error in cents - this case, -0.6 cents. One advantage of the phase display is that it generally provides more resolution than the spectrum display, except in the highest octave where the resolutions are about the same. For this reason the spectrum display is used for rough tuning and the phase display is used for fine tuning. False beats can confuse the phase display, though. So the spectrum display is preferred even for fine tuning in the high treble. In any case, both displays are available; so you can use whichever display seems to be giving the clearest indication. Toolbar TuneLab Pro uses a toolbar for many functions. Here is the toolbar from TuneLab Pro: New Tuning File - prepares for creation of a new tuning, and may start auto measure sequence Open Tuning File - selects and load an existing tuning file Save Tuning File - saves the current tuning in a file so it can recalled later Sound On/Off - toggles the sound generation mode on and off Note Lower - switches to the next lowest note. (Í on the keyboard also works.) Note Higher - switches to the next higher note. (Î on the keyboard also works.) Zero Offset - clears the offset to zero. (Z on the keyboard also works.) Lock Mode - begins locking onto the note by automatically adjusting the offset (“.” also works.) Zoom Out Spectrum Display - zooms out to show a wider range (“-” also works.) Zoom In Spectrum Display - zooms in to show a narrower range (“+” or “=” also works.) Auto Note Switch, Both Direction - enables auto note switching in both directions Auto Note Switch, One Direction - enables auto note switching in just one direction Measure Inharmonicity - measures inharmonicity or current pitch in over-pull (pitch raise) mode (M) Over-pull - enables/disables over-pull (pitch raise) mode (F2 also works.) Historical Temperaments - selects optional non-equal temperaments Tuning Curve - displays the tuning curve for adjustment or review (T also works.) All these toolbar buttons have associated tooltips. To see a tooltip, merely move the mouse cursor so that it rests on one of these buttons. After a short pause a box will appear with a reminder about what that button does, as shown to the right. If there is a keyboard key that performs the same function, the tooltip will tell you about it. 4 Current Settings Display In the middle of the main TuneLab display screen in large letters there is a display of the currently selected note. Above the phase display is a display of current settings. Usually most of these fields are blank; but here is an example with all the fields active: Here is a description of each of these fields, reading down the left column and then the right column: 1. Tuning File Name - the name of the tuning file currently in use 2. Temperament Name - the name of the temperament file (if one is selected) 3. Over-pull Percentage - the current over-pull percentage (if over-pull mode is selected) 4. Tuning Partial - which partial (or fundamental) is used for tuning the current note 5. Frequency - the calculated frequency, taking into account all offsets 6. Over-pull - the offset due to over-pull mode (or the temporary offset if over-pull is not selected) 7. Custom Stretch - the offset (if any) manually programmed for the current note 8. Template Stretch - the offset calculated from the tuning curve 9. Temperament Offset - the offset from the optional historical temperament in effect 10. Basic Offset - the offset (if any) applied to all notes uniformly 11. Note Switching - “Auto up” in this example, tells which form of hands-free note switching is in effect Microphone Level Indicator To help verify that your microphone is working properly, TuneLab provides a display of the microphone level in the upper right corner of the main screen. When all is quiet, the level should be below 1%. Normal talking into the microphone should produce a level of at least 50%. If the reported level is nowhere near these levels, then check your microphone and check the multimedia settings in your computer’s Control Panel to see if some system volume control is improperly adjusted. Tuning Curve Adjustment The following image shows the tuning curve adjuster. The tuning curve adjuster contains two different graphs. The upper graph is called the tuning curve. For each note from A0 to C8 it shows the calculated stretch in cents. It is this calculated stretch that appears in the current settings display under the name “Template”. The arrows below the tuning curve are for adjusting different aspects of the curve. There are three adjustment modes: fully automatic, semi-automatic, and fully manual. Normally we recommend the fully automatic mode. In fully automatic mode, the four inner arrows will all be replaced with the word 'Auto', and clicking on any one of them will make the fully automatic adjustment. There are three buttons at the top of the display that 5 select among the three adjustment modes. The display shown here includes just four adjusting arrows because the Auto-A0-C8 (semi-automatic) option has been selected. The lower graph is called the deviation curve. It displays information about the two intervals that are selected in the selection boxes just above the graph. As shown we have selected 6:3 octaves for the bass and 4:1 double octaves for the treble. Other intervals may be selected, depending on the kind of tuning you want to achieve. The deviation curve is divided into a left half and a right half. The left half is based on the interval selected for the bass (6:3 octaves in this case) and the right half is based on the interval selected for the treble (4:1 double octaves in this case). The deviation curve shows how these intervals work out in the tuning. Where the deviation curve shows zero, the selected interval is beatless. Where the deviation curve shows a positive number of cents, the selected interval is wider than beatless by that many cents. Where the deviation curve shows a negative number of cents, the selected interval is narrower than beatless by that many cents. When you use the adjuster arrows to adjust the tuning curve, you are directly affecting the tuning curve. As a consequence of your adjustment of the tuning curve, the deviation curve will also change. Therefore, even though you are directly adjusting the tuning curve, you may assume that you are adjusting the deviation curve as well. Generally, you make your adjustments to achieve a certain appearance in the deviation curve. The procedure for making these adjustments is described in detail in Chapter 2. 6 Partials Each note is tuned according to its fundamental pitch or the pitch of one of its partials. The current settings box shows which partial is being used. The selection of partials comes from a table of partials. This table may be modified from the screen shown to the right. The table shows the partial number for each note from A0 to B6. (C7 through C8 are assumed to be using the fundamental.) Using the < and > buttons you can lower or raise the partial for the highlighted note. You can highlight a different note by clicking on the partial number for that note. Since the same partials are generally used by a group of notes, the Duplicate button is provided to duplicate the highlighted partial into the next note and move the highlight. In this manner you can quickly set an entire section of notes to the same partial. The table of partials is stored along with the tuning curve in the tuning file when you save a tuning. So it is possible to customize the table of partials for each piano that you tune. Whenever you begin a new tuning, the table of partials is initialized from the special tuning file, DEFAULT, which is installed when you install TuneLab. If you want to make a change to the table of partials that will apply to all new tuning files that you create, then you can explicitly load DEFAULT as a tuning file, edit the table of partials, then save the modified DEFAULT, which will replace the original DEFAULT. Partials can also be changed on-the-fly using the function keys F3 and F4. These on-the-fly changes are not stored in the table of partials and are canceled when a new note is selected, unless you have enabled “Persistent Partials” under Edit Options, in which case changes made on-the-fly are immediately incorporated into the current tuning file. Inharmonicity Inharmonicity is the name given to the phenomenon whereby the partials of a piano string are not exact multiples of a fundamental frequency. TuneLab assumes that the partials are offset from their exact whole- number multiples of the fundamental by an amount that increases with the square of the partial number and is proportional to the inharmonicity constant for the given string. When TuneLab measures inharmonicity for a string, the pitches of all the partials of that string are analyzed and an inharmonicity constant is generated for that string. The inharmonicity constants are stored in the tuning file when a tuning is saved. You don’t need to be concerned with the actual values of the inharmonicity constants that you measure; but you can see and edit them from the Edit menu. In a well-scaled piano you can expect to see the lowest inharmonicity constants somewhere in octave 2. From there the inharmonicity constants increase slightly as you move down to A0 and they increase substantially as you move up to C8, as shown below. TuneLab uses the specific samples that you 7 collect to find a best-fit inharmonicity model for the entire scale. Using this model, TuneLab makes all the calculations regarding how partials relate to one another. Typical Inharmonicity Values for a Kawai Grand Over-pull Mode When raising or lowering the overall pitch of a piano by a significant amount, you will find that the notes that you tune first are changed by the time you are done tuning. This is due to the interaction of the string tensions, primarily through the bridge and soundboard and the flexing of the plate. When an entire section of notes is raised in pitch, the result is that the notes that were tuned first will tend to drop in pitch. Even the notes that you tuned last will drop somewhat due to the delayed settling of tension in the wire. Over-pull tuning mode compensates for this change by setting tuning targets that are a calculated amount beyond the desired pitch. In this way the change that occurs will leave the notes right where you want them. In many cases using just one pass with over-pull tuning can take the place of tuning the piano twice. Over-pull mode accomplishes this goal by making a quick one-second pitch measurement before you start tuning each note. The collection of these measurements is called the “over-pull history”. The most recent portion of the history list is displayed to the left of the selected note as shown below. The main purpose in displaying this list is to provide verification that the over-pull calculations are based on valid measurements. Sometimes during a pitch raise extraneous noise can trigger a false reading to be entered into the history list. The false reading can be corrected by re-measuring the current note. When in over-pull mode, the field normally used for the temporary offset is used to display the over-pull offset as shown earlier in the current settings. Temporary offsets are not permitted in over-pull mode (although you can use the basic offset for the same purpose). When over-pull mode is first entered you have an opportunity to adjust some parameters that affect how over-pull is calculated. The parameter that is most often changed is the over-pull percentage, and this can be done quickly while you are tuning using Functions keys F7 and F8. 8 Calibration TuneLab should be calibrated before you trust its absolute pitch. Without calibration, TuneLab assumes a nominal crystal oscillator frequency in its sound system and makes all pitch calculations from that assumption. By doing a calibration you are refining that nominal value based on a comparison to a trusted pitch source. You can do a rough calibration using a tuning fork, but your final calibration should be with some more precise source, such as the NIST phone service described later. The result of a calibration is a revision of the actual sample rate of the sound system, which is shown in the About box. Normally, calibration is done only once when TuneLab is first installed on your computer. See the chapter on calibration later in this manual for details on doing a calibration. Hands-Free Note Switching Using the menu or the keyboard you can enable different forms of hands-free note switching. There is auto note switching, which listens for and switches to nearby notes when it hears them. There is timed note switching, which switches to the next note after a certain delay time. And there is Auto Measure, which switches notes to sequence through a pre-defined list of notes that you want to measure for inharmonicity when starting a new tuning file. When any of these forms of hands-free note switching is in effect, note switches are performed just as if they had been done manually. The current note switching status is shown in the bottom center of the Current Settings box. . Auto Measure is initiated by starting a new tuning file. After the inharmonicity measurements are made, the note switching mode returns to whatever it was before. In TuneLab Pro, the different forms for hands-free note switching are most easily enabled with the keyboard. Shift-Right-Arrow and Shift-Left-Arrow enable auto note switching in the indicated direction. Press both arrows at once to enable both directions. Alt-Arrows enable timed note switching. There are also menus for making these selections. Auto Measure is initialed by starting a new tuning file. After the inharmonicity measurements are made, the note switching mode returns to whatever it was before. Auto note switching will switch up to three notes away from the current note. It can be enabled for up, down, or both directions. When over-pull mode is also e