This is an interesting project. It isn’t immediately obvious to me how the visualisations aid the tuning process. Please can you say a little more about how you expect a user to interpret those as they perform tuning work?

Pitch is an estimate based on sampled audio. Sometimes, it is not always accurately detected. Here, we have an additional visual cue that produces a stable/stationary waveform when the detected pitch is in tune with the selected reference note. A plucked tone has a slight variation in pitch from start to end; it rises and falls slightly. You can see this in the visual display. This would be very useful for fretting work, where each fret's tone is expected to have similar pitch variation.

I see. Was there an example of that in the video? Perhaps I missed it.

In what way does the visualisation vary when the note is not in tune? How does the visualisation indicate flat or sharp?

No. When sharp even by 0.5Hz the waveform rotates right and left when flat.

Perhaps it lets you get that last 1-1/4 of a hz that might otherwise get lost?

Its also probably really good for beginners trying on their own to train them selves so they can spot when they are over/under tune

It's just easier to quickly notice a pattern moving or standing still than the needle moving by a few degrees. The needle can also appear twitchy or jump around and lag, making it harder to tune accurately.

Pitch detection is computed and can sometimes be influenced by external noise or sampling limitations.It can jump. However, the visual display is based on the period of the reference note (or set frequency), allowing it to function independently of the detected pitch.

I guess this is a similar idea to the Peterson Strobe tuner? I think they have a rotating object which presents dark and light regions at the chosen frequency, which is a similar idea to building a visualisation on a set of samples whose length is the period of the chosen frequency.

Same basic idea, like an untriggered oscilloscope tuned to a fixed frequency/period.

This is a great answer. If I understood correctly: The feedback you give the user is different than a usual tuner in two ways: it is framed by the reference note, and is two-dimensional.

Yes. The pitch displayed and needle interface is based on measured frequency. It also shows the nearest note name based on this measured value. The visual waveform interface's stability is based on reference frequency set. There is still scope for improvements to detect the pitch variation of plucked strings and provide an analysis. The tuner supports Just intonation which are based on ratios. Here fundamental, fifth and octave have perfect ratios (1, 3/2, and 2) and they can be visualized. Kindly try if you have an Android mobile. There is also a play button to sound the reference note.

You can't tune an instrument to 1/4 of a hz. Temperature, humidity, mechanic impacts all constantly keep working on the instrument, changing it's tune. Instruments are not high precision tools.

Whatever features this app has, they're just visual fancy with no value.

Some of us use chromatic tuners to fast (lazy) check our CNC speeds and feeds. 1/4Hz matters to me, go Korg!

CNC machines ? Chromatic mode should definitely be useful. The visual feedback requires an accurate reference frequency. You may play with A4 value or ratios to get desired non musical frequency value.

If the weather is stable, my violin drifts less than 1/4 of a Hz over the course of a week, let alone a single playing session.

Wow, impressive stability. In case of violin (bowed instrument), the waveform stability is visualised very well. Closer to sine wave. I tend to see less harmonics than plucked lutes like South Indian Veena. Please select 2 or 4 waveform periods in settings, set the desired reference note and try.

Thanks. I've been looking for a new app to give me immediate feedback on my pitch accuracy while I play, because the violin has no frets and my ear isn't good enough yet to identify whether I'm a little sharp or flat on each note. I think realtime feedback could really help me train my fingers.

I'll post more detailed feedback in a day or two when I've had time to experiment. Hopefully you'll still be checking the thread.

Post your detailed feedback when you have time or e-mail us. Will be checking the thread. If there is even a slight variation of pitch w.r.t reference note the visual feedback will rotate. But, the feedback would give an idea about the deviation.

There are also tuning apps that draw the cent deviation as a line, I think the T1 tuner is one such app, you can see a line graph moving and vibrating as you play your note. A similar app to veena is the airyware tuner that shows the soundwave graph moving left or right.

> me immediate feedback on my pitch accuracy while I play

The visual feedback needs manual reference note settings. That is the only limitation.

> You can't tune an instrument to 1/4 of a hz

I mean you can, but for stringed instruments keeping it to an absolute is hard. its the relative that you care about, at least for an instrument with a static fret. pretty much everything other non-keyboard instrument is down to you to adjust on the fly.

when you are within 1hz you get a beat at roughly 1hz, which is normally fairly easy to pickup.

Its part of the reason why brass instruments are never "wide" in stereo on recordings, because they tend to phase like a mother fucker. (there are ways around it)