I participate a bit in a Facebook Harpsichord group (enormous, 5600+ members, but amazingly congenial), and have found that the almost universal tuning app of choice is PitchLab. Since I get asked by harpsichord customers for a recommendation from time to time, I decided to investigate. WOW! It's a great app!
The full name might put you off: PitchLab Guitar Tuner, a free app. But don't let that fool you. An "in-app" purchase to unlock all features (@$2.99) makes it an amazing tool. It has multiple displays, from meter type to an electronic emulation of the multiple partial strobe display, with some very inventive and intuitive options. It finds the note anywhere as soon as you play it (though not so good in the lower notes of octave 1 and apparently missing C8), and starts measuring. Together with the display, it gives you Hz to the 0.1, cents off to 0.5, real time - i.e., changing as the pitch produced by the string changes (not damped as on the devices we mostly use). It has pre-loaded temperaments, courtesy of Paul Poletti (from his http://www.just-say-do.com web site - which I recommend - and he has a review of PitchLab there).
I used it to tune a harpsichord, and found it very user friendly and accurate. I checked it against my SAT: I'd tune the note with PitchLab, then check with SAT, found it spot on. I wouldn't use it for tuning pianos, but I could if I used a Railsback chart like the ones they provided with Strobe tuners. IOW, it will only read at zero offset, no provision for measurement, storage, or other ability to deal with inharmonicity. Still, I think it will be useful for a lot of things.
In the first place, coming to an unknown instrument in unknown condition, with PitchLab open you can just play notes anywhere on the keyboard and get a quick and accurate overview of how far off pitch it might be. (That's a problem with RCT, for instance, where the standard tuning window is limited to 25¢ either side of target, so you can't readily see what you are facing without going to a bit of trouble). It will be particularly useful for my fleet of harpsichords at the university, which can go 100¢ and more from standard pitch seasonally - well, actually I usually just use a fork and tune aurally those times, but this would assess just how far each section is off, etc. Could be used for chipping, etc., hands free - note-switching is automatic at 50¢ intervals. Finding any pitch in Hz when that is needed.
Anyway, even as a toy, at $3 it is a steal, any practical usefulness is a bonus. It's a fun toy, lovely graphics ;-)
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Fred Sturm
University of New Mexico
fssturm@unm.edu
http://fredsturm.net
http://www.artoftuning.com
"We either make ourselves happy or miserable. The amount of work is the same." - Carlos Casteneda
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