Vinyl Rules!
Well-Known Member
Mobile phone apps have come a long way and now there’s one for audiophiles who still spin vinyl. With the app “RPM Pro” (Android/IOS 11.1 or higher) you can now measure the speed accuracy and stability of your turntable. It’s available for $15 and there’s a free version you can try a few times to see if you like it.
This app uses the gyroscope in your smartphone to read the rotational rate of your turntable platter, and variations in that rate. The conventional alternative is a test disc and a frequency counter, which could run $150 or more.
IMPORTANT USER NOTE: The simple peak-to-peak value the app delivers is more than twice as high as the weighted peak values from a Wow & Flutter meter, so no turntable will meet its manufacturer’s specs. In this respect the app is a bit misleading though it is accurate in itself. The value displayed is computed from data of speed (variation) over time and the app displays this as a waveform.
This is an extraordinary app, using the gyroscope in your smartphone to measure turntable speed and variation. Just remember it delivers a high peak-to-peak wow/flutter value that will be at least twice the quoted value.
Placement of the phone on your platter can affect results. The ideal location is to “center” your phone directly over the spindle on top of a record weight or clamp that is flat on top. A small plastic Scotch tape dispenser will also work. And the app is very sensitive: When I used it I found that a platter mat sometimes affected results.
This app uses the gyroscope in your smartphone to read the rotational rate of your turntable platter, and variations in that rate. The conventional alternative is a test disc and a frequency counter, which could run $150 or more.
IMPORTANT USER NOTE: The simple peak-to-peak value the app delivers is more than twice as high as the weighted peak values from a Wow & Flutter meter, so no turntable will meet its manufacturer’s specs. In this respect the app is a bit misleading though it is accurate in itself. The value displayed is computed from data of speed (variation) over time and the app displays this as a waveform.
This is an extraordinary app, using the gyroscope in your smartphone to measure turntable speed and variation. Just remember it delivers a high peak-to-peak wow/flutter value that will be at least twice the quoted value.
Placement of the phone on your platter can affect results. The ideal location is to “center” your phone directly over the spindle on top of a record weight or clamp that is flat on top. A small plastic Scotch tape dispenser will also work. And the app is very sensitive: When I used it I found that a platter mat sometimes affected results.