Gary, If you have already tried "two cheap ones" from Radio Shack without good results, the problem may be with your laptop rather than the microphones. To find out if your laptop sound system is in good shape, record something using the Microsoft Sound Recorder utility that comes with Windows (or with any other record/playback software). Record some voice and some music. Then play back those recordings through some fairly good speakers or headphones. Listen to the sound quality. Listen for excessive hum or distortion or extra sounds that were not there during the recording. If the recording sounds good, then you can be fairly certain that it will work fine for tuning as well. Sometimes a soundcard can fail in such a way that it still sort-of works, but it adds noise, perhaps even at a specific frequency, which will mess up certain measurements. Also, extreme distortion will produce true harmonics. If these distortion harmonics are stronger than the partials from the piano, then the inharmonicity measurment will think those harmonics are the partials, and you may get poor measurements. Robert Scott Real-Time Specialties
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