Platterwise: Turntable Speed

Platterwise is a turntable speed test, wow and flutter meter and alignment tool that tells you how far each reading can be trusted. Most phone speed apps read the gyroscope, and a gyroscope's scale can be a percent off. That's why two phones on one platter give two answers. Platterwise times whole laps with the compass, which has no scale to be wrong, so the speed you see doesn't depend on which phone you own. It works on phones with no gyroscope too. SPEED, THREE WAYS • Phone on the platter: no test record needed. 33⅓, 45 and 78 rpm, with a ± on every reading. It keeps running while you adjust the pitch, and buzzes when it has enough turns. • Test-tone record: speed from a 3150, 3000 or 1000 Hz track through the microphone. • Strobe disc: print a disc for 50 or 60 Hz lighting, with rings for dead on and ±0.5, 1 and 2%. Count the drift and it turns that into a figure. WOW AND FLUTTER • DIN-style 4 Hz weighted peak, weighted RMS, wow and flutter bands, drift and a speed trace. • The strongest rates listed, so you can see what is wobbling. • An off-centre record hole is usually the biggest wobble on a test track. Platterwise reports it apart, and shows the weighted figure with it taken out. ALIGNMENT • Baerwald, Löfgren B and Stevenson for IEC, DIN, JIS or your own groove limits. • Null points, overhang, offset angle and tracking error, with curves to compare. • Printable arc and two-point protractors drawn for your arm, on A4 or Letter. • Your printer got the size wrong? Enter what the 100 mm bars measured and the next PDF cancels it, even if it scales each way differently. • Check an arm as it stands from its maker's figures. CARTRIDGE AND SETUP • Arm and cartridge resonance, with the arm mass your cartridge wants. • Phono loading for moving magnet, and step-up transformers for moving coil. • A bubble level that takes out your phone's own error, and platter tilt with no calibration. • Hum and rumble check: a before-and-after comparison. TAPE DECKS TOO • Cassette and reel-to-reel: speed, drift and DIN-style weighted wow and flutter from a 3150 or 3000 Hz test tape, at 1⅞, 3¾, 7½ or 15 ips. • Every steady wobble up to 60 Hz is listed, so a capstan or pinch roller shows up by its rate. • Measure at the start, middle and end of a side to see speed change as the reels fill. • Watch the live reading while you turn a speed trimmer. • Flags a 3150 Hz tone that is really a 3000 Hz tape, which would read as 5% off. A LOG FOR EACH DECK • Turntables and tape decks. Stylus hours, setup notes and every reading, with speed over time. • See what a new belt changed. Share a PDF or CSV. Back up to a file. STRAIGHT ANSWERS A phone is a good guide, not a calibrated instrument. Platterwise says when a compass reading can't be used, when a tone is too noisy to trust, and when a run failed its own checks, and it shows you why instead of guessing. Test-tone readings are against the record or tape you used. The tape mode has been checked on simulated tapes only, not yet on a real deck. Your decks and readings stay on your phone, with no account. The microphone is used only during a tone or hum check, and sound is never recorded to a file. Ads show on the main lists, never while you measure, and an optional one-time purchase removes them.