Piano World Home Page Forums Our Most Popular Forums Piano Tuner-Technicians Forum Don Gilmore's thermal tuning system

Perhaps Don is measuring period by counting, using the system clock--no A/D required.

You appear to be a EE, so I can answer most of your questions with a few cryptic phrases:

FPGA.

264 counters.

32-bits.

300 MHz.

PWM.



Don A. Gilmore
Kansas City

Don, as long as the piano stayed in relative tune to itself, wouldn't your system be able to tune it even if it went quite flat? (Albeit not to concert pitch)

Wow. What a concept. If there are any photos or videos of the current prototype I sure would be interested in seeing it!

I suppose that's true...and quite brilliant! As long as you don't mind if the piano is tuned to A-439 or perhaps a little less, the standard values themselves could be universally detuned to keep it in range no matter how flat it goes! If a person did not have the need to play along with other instruments, or recorded music, then this would ensure tuning basically indefinitely.

This is a very interesting concept.

Don A. Gilmore
Kansas City

Don, yes, the piano would tune to the lowest acceptable pitch. I don't really see a lower limit except by increased inharmonicity.

Another approach along those lines would be to deliberately tune the new piano to a sharp standard, like A-444. Then, as the piano strings stretch over time, lower the tuning until it eventually reaches concert pitch.

I wouldn't necessarily have increased inharmonicity either. Rather than offset the original tuning mathematically, I could simply store several different real manual tunings. One sharp for the new piano, one concert pitch tuning, and perhaps an intermediate one.

Don A. Gilmore
Kansas City

Would the components of your system have the ability to make a note sustain indefinitely?

It would be interesting from a musical point of view if there were some mechanism like a sustenuto pedal that not only could allow certain notes to be sustained until they decayed, but stop those note's decay until the pedal is released.

So a pianist could - by using this special pedal - sustain certain notes as long as he wanted (like a violinist), eliminating a major limitation of pianos: their limited sustain compated to other instruments.

It's late and I'm tired, so I'm not sure that my question is perfectly clear; but I think you get the idea.

Hi frank,
I'm glad someone else suggested that. It'd be a bit like the pedals on an Organ. I'm sure Liszt would have loved it! (he had a piano/organ combo especially made)
I'm sorry if it's been answered already, so ignore me if it has, but what's the total Wattage of the system and will it give off detrimental quantities of heat? Could the heat change the voicing of the hammers?
Just for the record, it's a great idea in my opinion. I hope you suceed.
There will always be the need for quality technicians for voicing and regulation. It'd be nice to think that the money people save not paying for tunings would be spent on regulation and voicing, but I know that's quite naiive :-)
James

I believe i read that the power consumption is in the neighborhood of a household incandescent light bulb (~100 watts), and the strings are heated just enough to be about 20 degrees F warmer that standard room temperature, to allow for raising pitch as well as lowering pitch. So, the strings don't get hotter than human body temperature.

Yes, the sustainers will prolong the vibration of the strings indefinitely as long as they (the sustainers) have power. The system only uses them during the tuning process when the piano is switched on.

Actually, the sound of a sustained string is not quite as complex as a played string. The sustainer forces the string to vibrate at its fundamental frequency only, so it sounds more like a sine wave.

Don A. Gilmore
Kansas City

Don,

Do you have a link for the article that was posted in the Piano Technicians Journal?

It was published in the July 2002 issue. Here is a link to the original draft:

http://home.kc.rr.com/eromlignod/Se...uit%20of%20the%20Self-Tuning%20Piano.doc

My illustrations are at the end. Please note that the design has changed quite a bit since this article was written.

Don A. Gilmore
Kansas City

could it be pushed to 100 cents. key change.

You can get virtually any pitch change with enough power. But there is a practical limit to how much power you can get from an ordinary 120-volt household outlet (about 1800 watts). There would also be a limit, at some point, when string temperatures would get too warm. I'd say that 100 cents would probably be a little excessive.

Don A. Gilmore
Kansas City

Hi Don,
is it possible that a system which constantly adjusts its string tension between tuned and de-tuned may have new fatigue type problems?
For example, could the pins work loose?
I'd be interested to know who you've tried to develop this with. I'd imagine that with the backing of the likes of yamaha - who already have huge quantities of elecronics knowledge, engineers etc, the whole thing could be completed and implemented quickly. They sell tens of thousands of these things to schools - if a piano is tuned three times a year at £40 a pop, then they would argue that a tuning system of £1200 would pay back in ten years. I think that'd look quite attractive economically. If they can sell clavinovas for £700 with profit, I'm sure your device could be made for much less than £1200?
Or am I totally wrong?
good luck,
James

Well, it's actually easier to justify than that. Your payback estimate is correct...um, that is, as long as you only push the button three times a year! Remember that with this technology you can tune every day (like other instruments).

Your fatigue question is a common one. Fatigue only occurs when an object is subjected to cyclical stresses above its endurance limit, and even then only over millions of cycles. The pounding and vibration of the strings during normal playing is much harsher than these tunings would be.

I originally teamed up with Story & Clark (QRS) to produce the device in their pianos (Prelude grands). Unfortunately, due to financial problems, etc., they sat on the contract for five years and never "got around to it". That's why there has been a vacuum since 2003.

They were, however, paying me minimum yearly royalties the whole time. I finally terminated the contract and now I am using that royalty money to build a production-quality prototype myself. Steinway, Petrof and Estonia have all expressed interest in it over the last year or so. We'll see who picks it up.

Don A. Gilmore
Kansas City

Congratulations Don!

I believe that will be a major step in the evolution of the instrument which has changed so little in 300 years.

It sounds unbelievable! Just push a button and have your piano tuned in two minutes!

I don't fear about beeing puted out of bussiness. I guess our bussiness as tuners will evolve as the piano does.

That's amazing. You won't have to be an accomplished great pianist to have the benefit of playing always in well tuned pianos.

Even students in music schools will play pianos in tune all the time.

That's wonderful!

Perhaps one day we will see pianos with this self tuning system and maybe glass sound boards as being the norm, and if they work like advertised, I'm all for it and may even buy one. Gibson made a guitar recently that tunes itself..

http://www.gibson.com/RobotGuitar/story.html

I do believe it is the bridge that is used to change the strings pitch but a friend of mine recently bought one and is very pleased with it.
Anyways, congrats Don and I wish you all the best in your endeavors.

Hi Don,

How is it going...any news on when we might see/hear your invention?!! Looking forward to it!