My name is Steven Norsworthy, professional engineer and professional musician. I hold advanced degrees in both fields. My engineering background is in Signal Processing. My musical background is in instrumental performance.

I invented the new device named PianoSens, an electronic sensor that directly measures the motion of a string without sensing the unwanted byproducts from the ‘Piano’s Acoustic System.’

PianoSens is not a microphone. It reads the direct motion of a string. A microphone, however, picks up an acoustical waveform related to its specific location in the piano. There is a ‘myth’ that the microphone type and location does not matter in piano tuning. This is far from the truth. A microphone feeding an electronic tuning device (ETD) app measures many partials and comes up with a net assessment of tuning offset from its overall ideal value.

Using a microphone, my studies show that the overall frequency assessment can vary as much as 1 cent from location to location, not so much from variances of the fundamental but from inaccurate measurements of the upper partial frequencies. These variances are caused by several factors. Firstly, variances may come from undamped strings interfering with the desired upper partials, so that the desired upper partial frequencies are blurred and cannot be accurately resolved. Secondly, variances may come from acoustical nulls and peaks related to the physical location of the mic with respect to the wavelengths of the desired partials,  such that a desired partial is nulled out and effectively missing. Tuners experienced in using ETD’s have noticed that if they just move their mic a small bit, that they can easily see a change in frequency measurement. They also know that the measurement indicator (strobe or needle) in the user interface can have a lot of jitter, making it hard to know what number to read and at what timeframe to read the number after the hammer strikes the string! PianoSens is able to significantly reduce these variances to within a fraction of a cent, typically 0.1 cents, depending on the ETD’s own accuracy. ETD apps will have to improve and revise their algorithms to take advantage of the increased input accuracy from PianoSens. This raises the bar on the ETD app makers to start using the most modern advanced signal processing algorithms for frequency accuracy.

Some ‘false beats’ are ‘heard’ from acoustical interference unrelated to the individual string vibration, while some false beats occur within the physics of the string-to-bridge coupling. PianoSens is able to ignore all acoustics by only ‘reading’ an individual string vibration. PianoSens is ‘deaf’ acoustically. Using PianoSens, the human piano tuner could have hearing deafness and yet outperform the best aural tuning, as our ears are essentially microphones suffering from the same acoustical issues.

Therefore, PianoSens becomes an essential tool to the piano tuner. The tuner does not have to dampen the undamped upper strings and duplex strings of the piano to get accurate tuning. Often, beanbags or felt strips are used. This is now unnecessary with PianoSens. Tuners are often tuning in a noisy environment, and since PianoSens is acoustically deaf, it does not matter how much acoustic noise there is going on during tuning!

PianoSens is mounted on a sliding ‘sled’ and is easily and quickly repositioned from note to note so that it may focus on the note to be tuned. This sled uses a magnet to hold its position securely over the desired strings. The bottom surface of the sled is smooth and nonabrasive to the strings. PianoSens has just enough dynamic range to cover one unison set away so that it may be used with upright pianos and not interfere with the hammer striking the current unison set.

PianoSens is shipped with an XLR-to-USB interface. The interface is essentially comprised of a preamplifier, followed by a 24-bit analog-to-digital converter, followed by a USB format converter which is universally compliant with most computers and portable iOS (or Android) devices. This allows the ETD apps to recognize the signal as an external microphone even though the physical device is not a microphone. The interface comes with several cables for universal device applicability.

PianoSens devices are produced by a manufacturing partner in their state-of-the-art aerospace facility in the USA. The devices have the highest level of manufacturing compliance and quality.

PianoSens devices are currently made to order, and take about 4 weeks to ship once the order is placed. PianoSens orders are initiated on this website http://PianoSens.com. Order fulfillment is through PayPal. PianoSens orders may be initiated with a 50% deposit. Once the deposit is placed, the device will be made and a final invoice will be sent once the device is ready for shipment.  The final invoice will reflect the remaining balance, plus applicable sales tax, shipping, and handling. PianoSens price is $600. Typically, shipping and handling within the 48 states is around $50. State sales tax is applicable to California.

The parent company of PianoSens is my engineering corporation, RF2BITS, Inc.

I’m here to answer your questions and help you purchase product. You may write me at [email protected].

Thank you.

Steven Norsworthy