RPM - Turntable Speed Accuracy

The best turntable speed and accuracy testing mobile app available.

See the RPM speed variations, wow/flutter, of your turntable in real time graphics like you've never seen before.

Test the RPM and wow/flutter accuracy of your turntable, whether 16, 33 1/3, 45, or 78.

Now with the Worldwide RPM Turntable Accuracy Database you can research what other RPM users are finding out about their turntable's accuracy and what they think of them, + Stats of the most popular TT makes & models

● RPM is proud to be recommended by Rega Research Ltd, makers of some of the best turntables in the world.
● Great review by top tech vlogger Techmoan on Youtube
● Used in high end TT reviews in Stereophile magazine

Save all your rpm tests in My History for reviewing or sharing later.

RPM uses the gyroscope in your iPhone to determine the rotation speed of your turntable, automatically determines which speed setting you're on, and reports how accurate it is.

Simply place your iPhone on your turntable, close to the centre but doesn't have to be over the centre spindle. As the iPhone rotates the display will remain stationary from your perspective for easy reading.

The UNIQUE feature of RPM is that it shows a scrolling graph of the rpm accuracy variation over time, this shows wow/flutter effects, especially those associated with the turntable not being level, belt wear, etc. You can even detect the small drag caused by the stylus resting in the grooves.

You can even visualise wow and flutter variations plotted actually around the vinyl centre to show a heat map of exactly where in the turntable rotation the inaccuracies occur.

There are many ways of testing the average RPM of your turntable, some turntables even have this built in, however there is no other practical way of showing the wow/flutter variation over time than RPM. The average RPM may look great however a large wow/flutter will make the sound terrible, RPM will help you identify the problem and visualise improvements you make.

For Upgraders the history graph parameters can be customised to:
- Set the moving average sample size.
- Accuracy at which to turn the rpm circle sold green.
- Set a duration after which the display updates will freeze so they can continue to be read after the turntable is stopped, this is also required to save sessions to History and upload to the World TT DB
- detect and graph 16, 45, & 78 records.

Calibration Mode is here! (Upgraders only)
The RPM realtime display is reliant on the iPhones gyroscope accuracy, which is normally very accurate, if you suspect yours isn't quite right then you can now use Calibration Mode to auto test and then apply any necessary correction in real time.
This auto calibration uses the compass to count the turntable revolutions, if you have an older iPhone (not iPhone 6S or newer) then this may be unreliable, in this case you can still add your own multiplier if you have done an independent calibration.
Extensive testing means we're now confident that using RPM can help you setup your turntable to be within 0.1% of its target RPM, assuming your turntable can be adjusted and is itself stable within that tolerance of course.
Use 33 1/3 rpm for auto-calibration as at 45 and 78 rpm the compass simply won't be able to keep up.
Note that calibration isn't normally required, and that only uncalibrated sessions may be uploaded to the World TT DB to ensure all data is comparable.

Now with the World RPM Turntable Performance Database, accepting submissions from RPM users worldwide to build the ultimate resource for researching the most accurate turntables out there. Upgrade to join in and upload your own TT data, go to Settings and make sure you have the Freeze time set then do an RPM session as normal. At the end of the time you will can name your session after which you will have the option to upload it to the World DB. You can always upload from History later too.

Download for free and give it a try.