Excuses and Misinformation
Over the years we have heard many excuses for why the piano inharmonicity formulas don't work. But we know they do and our competitors continually come up with their own theories in an attempt to debunk our formulas that have been working perfectly for years. When the first software competitor made the claims, Al Sanderson created a tool to electronically stimulate the strings to see if there were errors in our formulas. As it turned out, the formulas were fine and are used by many string manufacturers to create better sounding scale designs for pianos. The errors were in the measuring instruments used by the competitor. In response to the false claims, we gave a class titled "Inharmonicity - Fact and Fiction" in order to present our findings. So, our embarrassed competitor threatened us with lawsuits and a lot of other nonsense.
We Are the real Deal
Al Sanderson and his son have been very involved in scale design, bass string manufacturing, and other piano-related studies for a very long time. Al was the first scientist to study and uncover the mysteries behind inharmonicity and created the mathematics necessary to predict it. When the right measurement equipment is used and the inharmonicity formulas are used correctly, there is very little variation between our predicted inharmonicity and the actual inharmonicity.
This was proven almost thirty years ago by the highly-respected Steve Fairchild. Steve would measure the physical strings, calculate an 88 note tuning with the inharmonicity formulas, tune the piano and the tuning would be "perfect" to Steve's ears. Steve essentially a full circle: physical (measure the strings) to theory (inharmonicity formulas) back to reality (tuning the piano and aurally verifying the results).
MAYBE What you think you know is wrong
There is much misinformation on inharmonicity, spread by competitors with less accurate devices. It reached the point where no one questions the misinformation and accepts it as fact.
The easiest method to learn the truth is to match the tuning accuracy of an Accu-Tuner against a competitive device. We are confident that the tried-and-true original ETD provides a better tuning in less time.