Beta test of pianoscope v2.5

Frank Illenberger

After three months of development, I am excited to release the beta version of pianoscope 2.5 to TestFlight. It comes with some very cool new features which I describe below.

If you are interested in trying it out, feel free to install it via the following link:

https://testflight.apple.com/join/vDuZpHaQ

Note: To use the test build of pianoscope, you'll need to make an in-app purchase, even if you've previously purchased the app. However, rest assured that this is only a test transaction and you won't be charged for it. If you wish to return to the release build, simply re-download it from the App Store app.

I'm curious about your experience with this and would greatly appreciate it if you could share your thoughts.

New Features

Audio

There is a new Audio section in the general settings with options for recording and playing audio.
The new audio settings contain an Input section with which you can control, wether pianoscope should prefer the built-in microphone or allow input from a Bluetooth headset. There is also a new graphical input level meter.

Tone Generation

When using headphones, the tone generator is now automatically reacting to notes played on an instrument and adjusts the generated pitch accordingly. This enables a novel way of electronically assisted tuning or training in which the tuner simply aurally matches the current pitch to the guiding tone played by pianoscope, similar to aurally tuning unisons. By enabling the new As long as piano tone sounds option, tones are only playing while you are actually tuning a note. If you enable the new Headless Tuning option in the audio settings, you can even tune while your device is locked as no visual feedback is needed. I consider the new tone generation features experimental and would love to hear your feedback.
The tone generation section in the settings now allows to control the usage of Bluetooth and the built-in speaker for sound output.
Tone generation can now be started and stopped by tapping on the new speaker item on the left side of the main toolbar. Tapping and holding it reveals a menu for quick access to some of the tone generation settings. The old main menu item for tone generator has been removed.

When using a headset, tone generation can now be paused when playing a note one semitone below the currently tuned note. This is useful if you want to quickly deactivate the tone generation for aurally tuning a unison. You need to enable this feature with the new tone generation setting Semitone Down To Pause. To resume the tone generation, simply play any other than the last two notes.
The tone generation can also be started and stopped via the headset remote buttons.

Partials view

The partials view is now visualising the partials played by the tone generator. By tapping on an individual partial, the generated sound is reduced to the selected partial. When you select a partial bar, its inharmonic offset in cents is displayed in the top right corner of the partials view.

You can now visualize potentially beating partials. By tapping and holding a key on the on-screen piano keyboard you can now tap an additional key with a second finger to define an interval. The partials of the first key are shown in orange and the partials of the second key in blue. If you have activated the tone generator, it will play both tones for both interval notes. If you select a partial collision, you will hear the resulting beat and the beat frequency is shown in the top right corner of the partials view.

The partials view now has its own section in the general settings.
There is a new option Assign To Keys. If you disable it, the partial bars won't be horizontally assigned to their respective key. Instead they are arranged linearly next to each other. This enables showing partial bars independently from the on-screen piano keyboard. If you deactivate the new option Hide With Keyboard, the partials views stays visible if you hide the keyboard.

You can now completely hide the pitch display using the new Pitch on/off switch. This gives you more space for showing the partial bars. On small devices this is a good setup for doing intonation work.

Besides the existing Continuous and Hold modes, the partial view has a new display mode called Expected Values. In this mode, the partials are displayed according to the inharmonicity measurements.
Some of the partials options can be accessed by tapping on the Partials label in the top-left corner of the partials view.

Tuning View

The settings for the textual display of the current tuning state have been overhauled. They now also allow to display the deviation of the currently sounding tone from an unstretched, harmonic tuning in cents. This can be used for all kinds of measurement purposes, for example scoring PTG tuning exams.

Indicator Freezing

The pitch of a piano tone is not always constant during its decay. In the midrange, it can fluctuate by a few cents depending on the force of the keystroke. In the treble, undamped and duplex strings also influence the perceived pitch and the display of pianoscope. As a piano tuner, you decide in such situations which sound phase of the note to focus on. In the midrange, it is common to use a later phase of the tone, for example, from 2 seconds after the strike. In this phase, the pitch variations are less pronounced between different keystroke strengths. Using your eyes, you then determine the center around which the red indicator or the stroboscope moves.

However, tuning according to this late phase does not necessarily lead to optimal results, as it occurs less frequently in played music. Therefore, it is advisable to orient yourself to the pitches shortly after the strike, as our musical perception is particularly sensitive to the beginning of tones.

The new Freeze function of pianoscope allows you to do just that. It fixes the position of the red indicator at a defined time shortly after the strike with a gray line.

Depending on the register, the freeze time varies between 300 and 500 milliseconds.

You can activate the freezing of the indicator under Settings > Pitch > Freeze.

Use the Freeze function as follows:

Dampen all the strings of a unison except for the one you are currently tuning.
Strike the note slowly and repeatedly as evenly as possible in mezzo forte.
Focus exclusively on bringing the gray, frozen indicator to the zero position on the scale.

Tune all strings of a unison in this way.
In the high treble, place the device microphone as close as possible to the string being tuned to capture as little resonance from other undamped strings as possible.
For fine-tuning in the high treble and in areas where the duplex scale resonates strongly, wait between strikes until the resonances of the undamped strings have somewhat subsided.
In the settings for the textual display, you can determine whether the text remains on the frozen indicator, or whether it continues to move with the red line after freezing and displays the corresponding values.

Changes:

When setting up a new document, it is now possible to only measure one note in each octave and already able to use the tuning function. This can be useful for setting up a preliminary tuning curve for large pitch raises, where you now may start by bringing a small number of strings up to pitch.

Fixed Issues:

The tone generator did not respect the current overpull during a pitch-raise.

Burkhard

Hello Frank,

I am very much looking forward to the new functions.
Do you have a new invitation code for Testflight?

Frank Illenberger

The link to join TestFlight is at the top of the post. Here it is again: https://testflight.apple.com/join/vDuZpHaQ

Stefan Borowicz

Wow...lots to unpack here! It will require a few read-throughs and experimentation. I'd love to see a video of these new features in action... (hint hint...) ;-)

MilanDka

It looks interesting and it really tunes up the discant nicely. I was expecting more of a function: when I tune 1 tone - first string - I tune to zero, second string ear to the first and third ear to the previous two. Now if I measure the whole tone, it will be lower on the tuning rod and so I have to tune the first string a bit to get the whole chorus at the right pitch.
When two or three unisons are in unison, the whole chorus is a little lower on the tuning machine.

Translate to Czech: "Allow Bluetooth" = "Povolit Bluetooth"

FloydG

I tried out the process of raising pitch with the use of the tone generator this afternoon. I see some real pedagogical value here, though I'm not sure this feature is practical for regular in-the-field use. Though I could be wrong about the latter. I was very happy about much that I experienced as I went through the process.

One detail to think about. Pitch raising in this kind of context usually involves tuning unisons-as-you-go. I found the tone generator useful for setting the first string of a unision, but since the pitch of a note in larger pitch raises is a moving target almost from the get-go, the tone generator was just in the road when it came to pulling the other strings in to match the first. I was reaching over an turning the tone generator on and off for every note I tuned.

Maybe I am pushing in the direction of too much complexity, but it strikes me as being useful to have the program accommodate this approach.

I use a split mute. I tune the center string of a trichord, then move the mute one note to the right. I can then pull in the left string of the first unison and move on to tuning the center string of the new note. The next time I move the mute to the right I can bring in the left string of the first note, the right string of the second and the middle string of the third. I am aware that there might be other approaches to this task.

If the tone generator could be deactivated by the program when the note below the "current note" is played, and triggered on again only when the note above the "current note" is played, this would accommodate the aural pulling in of unisons without the unnecessary presence of the generated tone.

MilanDka

For me personally, the tone generator is of very little use, I tried it twice - only the center of the piano. The resulting tuning was very wild and runny. It was at a time when it was not possible to connect headphones via bluetooth - I have Airpods Pro.

And the debugging process? The most accurate way is to tune the right string of the piano according to the tuner - it tends to be the least false, and then tune the remaining strings by ear.
Which is better for the freeze function? Tune each string by Pianoscope (very slow for the factory) or tune one string by the Pianoscope and tune the rest of the chorus by ear?

FloydG

I have not yet pursued the Freeze tuning, since my aim is in a completely different direction. I have a young protégé whom I am preparing to induct into the world of aural tuning.

Ed Sutton's post on the Pianotech Forum captured my imagination

https://my.ptg.org/discussion/a-new-way-to-learn-to-tune-a-piano

I understand the Freeze tuning to be a technique that allows for the very accurate visual tuning of unisons within a specific time window after the onset of attack, perhaps most helpfully applicable in the high treble.

The first time I got any real momentum in the field of piano tuning, I embarked on a path that made me over-reliant on visual feedback. I passed my RPT exam aurally, but that dimension of my skill set remains weaker than it ought to be. The thought of using a tuning app to tune the budding technician, rather than simply to tune the piano, is very appealing to me. Pianoscope is offering features that appear to support such an endeavor in a fresh and innovative way.

[deleted]

Today I found a very helpful use of the Freeze to clean up a unison wobble. On my B3, the left string had a little wobble by itself, tending to wobble flat back and forth from zero, coming off the attack phase, while the center and right strings were more steady. When I played them all together, the attack sounded great but the left string was contributing to a group wobble about 1 second later. So I tuned the B3 left string about 0.5 cents sharper off the Freeze attack indicator while leaving the center and right strings tuned at zero on their Freeze indicator. The result was all three strings in unison had very little wobble after the attack and were more in tune on the attack as well. So, Freeze to the rescue! I was not anticipating this benefit for using it as a solution in this way.

[deleted]

Before I had Frank implement the Freeze indicator, I used PianoScope in a pseudo-freeze mode by tuning each individual string a few tenths of a cent sharp on the attack and letting it settle a few tenths of a cent flat, then when the unisons were unmuted and played together they would typically strike the attack at zero and settle nearly a cent flat. The degree of overshoot and undershoot would vary, of course, depending on the register of the piano. The higher the register, the more variance. Now with Frank's Freeze indicator, this can be done with a far greater degree of precision. If I find one string of the unisons with more variance than the others (typical), then I tend to tune that one a little sharper on the attack than the others. Then it washes out in unison.

Johnny

I would like to see some video demonstrations using the audio feature. I see it useful for learning...any practical application, i.e. pitch raise.lower? Curious how others are using this.

FloydG

Johnny,

This is not a video, obviously, but yes, the audio feature can be used for pitch raising and lowering. I've outlined one limitation I have experienced above, but beyond that, it does provide some practical utility. Once measurements have been taken for inharmonicity and existing pitch levels, the generated tone can be activated as a reference pitch to which each note can be tuned. I'm not sure how accurately I can tune monochord unisons -- I made use of the visual display there -- but given a decent set of headphones, it is possible to correct pitch pretty accurately using aural targets that reflect the idealized tuning curve and the existing inharmonicity characteristics for the instrument at hand. Certainly useful in a situation where there is a desire to minimize visual dependence and cultivate aural skills.

[deleted]

I went back and re-tuned my Fazioli F308 to ensure that unmuted unisons as an ensemble did two things:
1) Hit the Freeze indicator to within 0.2-cent
2) Slow wobbles (as seen in the red indicator and heard audibly) should be minimal coming off the attack. The wobbles are not to be confused with the natural decay in pitch (as amplitude decays off the attack) which occurs in all pianos, especially in the mid and upper registers. This is not the wobble but the FM decay as amplitude decays. I tune out the wobble by taking the single string that moves the most coming off the attack and over compensate for it by stretching its tuning a 0.2-0.3 cents in the opposite direction of the wobble range. This usually works well. If that does not do the trick, then I check string leveling for any phasing that may be happening. I also check any string termination issues at the bridge and A-graf. This is well worth the time spent to get the most stable unisons possible.

I then play parallel 12ths through the whole range, esp. low-mid and mid-upper, and listened for a beatless clean sound that is clear and brilliant on the attack and sustains well as both amplitude and pitch decay. I was able to find one 12th which I perceived as just a little bit less than perfect, and it led me to one of the 6 six strings that was just a little off by a few tenths of a cent. This '12th Test' is what I call it, and it is a really great 'acid test' of achieving near perfection.

Then I played the ‘chorale’ section of the Chopin Nocturne Op. 48 / No. 1. It is full of a very rich ensemble of chord combinations and some of which greatly expose anything that is even the slightest bit off in the piano.

FloydG

MilanDka proposes a different approach for tuning unisons-on-the-go that does not seem to involve the kind of backtracking I described above. Even in that case, if hitting the note below the active note (or any note below it) turned off the tone generator, that would constitute a very simple switch enabling the pulling in of the unisons without interference. Striking the next note above for which a tone has not yet been generated could serve as a simple “on” switch.

Frank Illenberger

FloydG This is an interesting idea. Let me think about this.

Frank Illenberger

FloydG I've implemented your idea in build 1116. There's now a new option under Settings > Audio > Tone Generation > Semitone Down To Pause
If you activate it and you are using a headset to tune, the tone generation is paused when you switch to the note one semitone below the currently tuned note. By playing any other than the last two notes, the tone generation is resumed.

FloydG

I like it!

MilanDka

"Freeze" is an absolutely great feature. As I wrote in another discussion, I would add an enable/disable "Freeze" button to the status bar, as it's not as important in Pitch Raise since the capabilities of the indicator are not such that significant differences are visible.
Therefore, it would be good to have this quick option in plain sight.

Frank Illenberger

MilanDka Thank you for the feedback. I will be thinking about it.

I see two other possibilities for solving this:

Having an option for automatically switching off freeze during pitch raises. (Rick suggested this).
Having an option for the pitch raises to choose between two display modes:
a) The current mode: Using a linear indicator scale with overpull marker triangles
b) A new mode: Using a non-linear indicator scale with the overpull target being in the middle at zero, and marking the original tuning target with a thin line.

Mode b) would have the advantage of having more precision and the freeze would work nicely. You would not have to switch it off. A downside would be that it would be not as intuitive to grasp how much you are overpulling.

What do you think?

Burkhard

Frank Illenberger Mode b) would have the advantage of having more precision and the freeze would work nicely. You would not have to switch it off. A downside would be that it would be not as intuitive to grasp how much you are overpulling.

Moin Frank,
have you already implemented this option?

MilanDka

Automatic unfreeze on Pitch raise - maybe . But it does show differences in the high notes.

Probably a better choice would be B . It would be worth trying both options.