Precision Strobe Tuner 1.63

A General Purpose Chromatic Musical Instrument Tuner App with special Piano Tuning Functions.

The Precision Strobe Tuner main screen features are the Spectrum Display, the Note Dial and the Strobe Display.

The central Spectrum Display shows the input spectrum wrapped around the Display, with each Octave drawn in a separate color. The Note Dial is marked like a clock with the twelve notes of the Scale. All overtones of the input are shown as peaks in the Spectrum Display pointing towards their corresponding Notes. The Fundamental Indicator Tic on the Spectrum Display shows the Note of the Fundamental along the Note Dial, with the color designating the Octave. Use the Spectrum Display for coarse adjustment by tuning the Fundamental to the center of the desired Note Indicator.

As the input approaches the desired Note, a Two Group pinwheel pattern becomes visible rotating in the Strobe Display. Fine tuning is accomplished by adjusting to stop rotation. The Strobe Display responds instantaneously to changes in pitch and is extremely sensitive. The outside Strobe Display works just like a classic rotating disk strobe tuner. The Two Group pattern rotates CCW when the input is flat, and CW when sharp. When the rotation is stopped, the note is in tune.

The first screen shot shows the display tuning a Guitar Low E string. The Fundamental appears as an Orange peak in the Spectrum Display. This string rings bright, so the overtones are also dominant in the Display. Several other screenshots show the display for other Guitar Strings.

The second screenshot shows the display for an E 440 Tuning Fork with the Calibration Dial enabled and set. This Fork is 1.3 cent Flat.

The third screenshot shows the Input Signal Scope/Spectrum Display Page.

The PST also includes a Programable Temperament Function with 5 user definable banks. The final screenshot shows an example of a Temperament Bank setup to a typical Piano Stretch Curve. This can also be used for tuning alternate temperaments, pedal steel guitar setups, or special guitar intonation systems.

In addition, there are several Special Measurement Banks used for String Inharmonicity characterization and Piano Stretch Curve Calculation. Individual strings are characterized by measuring the Fundamental and 2nd Harmonic separately. By careful selection of a few representative measurement points, a reasonable smooth fit Piano Stretch Curve can be generated. Any number of measurements up to C7 can be used.

The Detailed Operation Manual can be viewed here:

The Precision Strobe Tuner Lite version is available for free download to evaluate and verify operation before purchasing.

What’s New

Version 1.63

Improved Note Tracking Stability.

Added Low Frequency and 60Hz Noise Rejection Setting to Note Tracking Settings Page. Useful in some situations on newer iPhones with improved Low Frequency Sensitivity.

Show additional information in the new Input Signal/Spectrum page to the far left of the Settings section.

Previous update fixed a major bug which caused the Strobe Display to malfunction for notes lower than about A440 due to a change in hardware audio sample rates on new iPhones.

Previous update fixed a bug involving the microphone permission request on IOS10.

Ratings and Reviews

4.8 out of 5
6 Ratings
6 Ratings
H.V.Information ,

Fun but

It is theoretically possible to indicate a pitch more accurately than an instrument can dial in or a string can make. This tuner makes us think that it provides that means and compels you to try, to play with the app like the cool toy it is. The bottom like though is how it all sounds when you're finished and how easy it is to use.
It doesn't sound that good and endless fiddling required.
I've checked out all my instruments learning what I can do and how to do it. I give this app 5 stars because it's fun to play with, not because it's a good functional tuner. I haven't tried a strobe tuner before so I have nothing to compare it to.
The down side is it's not a practical option during a live performance.
The fact that it uses the audio microphone is problematic. It's only useable in a quiet place. It rather needs a contact pickup able to clip on your instrument. According to the instructions there's a pickup that plugs into the charging port and you need that because the headphone/microphone jack feeds in through a band pass filter that ignores frequencies below 150 cycles which means the iPhone or iPad is designed to be deaf to bass notes. I haven't found a pickup configured with a plug which uses the charging port.
The manual octave selector pops out of lock every time the note is tested. When it does, the band pass filter drops out and then the display is momentarily chaotic and you reset and try again; lots of playing around. I can't make the custom profile feature work, so maybe it doesn't.
So, try this app, it's free to try.

jovino ,

Worth the price.

It saved my butt in the studio. Worth the money just for that.

Fgyjgfdhccfv ,

Had for years, some issues

This tuner has been great over the years, but lately, maybe it's the iPhone 7, it's been harder to use. I bought the "big one" and it's so easy to tune, albeit probably 5 times the price. This is a good tuner, I've just had problems with it as of late. Hate to say it.


James Campbell
1.2 MB
Requires iOS 6.1 or later. Compatible with iPhone, iPad, and iPod touch.
Age Rating
Rated 4+
© James Campbell


  • Family Sharing

    With Family Sharing set up, up to six family members can use this app.

More By This Developer

You May Also Like