And, if the piano is already 1/4 tone flat? Which happens here in Michigan every winter. It would heat the wires and tune it flat, apparently, leaving the piano flat of pitch?

I can't help but wonder what heating the strings might do to the felt of the hammers and voicing, eventually, after many hours or days of use.

This is an awesome idea and I'd LOVE to have it on my piano.

I tune my piano myself and am very aware of how quickly they become 'imperfect'.

To be able to have it perfectly in tune every time I play it would wonderful.

Mr. Gilmore has been working on this a long time and I feel certain he has the majority of the bugs ironed out. I expect a few additional problems could crop up if it's put in full production somewhere. The questions here are definitely valid to help me understand how this works.

Mr. Gilmore can feel free to install it on my piano free and I promise to demo it for anyone

Good job.

For someone who is worried about the heat issue, it would presumably be possible to tune the piano less sharp, and so require less heat for it to be in tune when the system is activated.

The drawback would be that the tuning would fall below A440 more quickly, and so would require a manual tuning more frequently than otherwise (but still much less frequently than a standard piano).

Don Gilmore, you have a PM.

Wow, this is a brilliant idea!

Not sure if it will remove the need of a conventional tuning from time to time in areas where seasonal temperature and humidity changes are big and piano is in a room where they are not controlled, but anyway, it looks very promising.

Regards,
Kurt.-

You could have the system alert you when an individual string is flat. Then the user could raise that one string enough for the piano could maintain 440. With such a system, the end user need not be a great tuner, just don't break any strings

By the way, I also am of the camp that needs to see a better end result before I become convinced.

Yes, the alert would be a nice addition. It's an innovative idea, I'm still not sold on the idea of needing to continually run a current through each string. I think for the system to be more effective it needs to be augmented and I have some ideas. One feature I would like to see is the ability to continually correct the tuning of the strings during a performance if need be. But like I said, I think the system really requires an extra component that it's currently missing.

I am still waiting for a system that will play the notes I meant to play, rather than the notes I did play!

It's been done -- it's called MIDI!

Never in my life have I wanted to play like MIDI plays.

All of these mechanical methods just suck the life out of music.

MIDI is "perfect" in the sense that everything is correct -rythm, pitch, etc- but is too mechanical. Therefore, you can say music is never perfect, but it can get close.

It will also perfectly reproduce a real performance that you record to MIDI format - with all its imperfections in timing, velocity etc. Of course, if you just use a sequencer to create your MIDI stream, then it could seem too mechanical - except all modern programs have algorithms to put imperfections back in to make the performance sound more human. A MIDI recording of a real performance is just like the piano rolls of years gone by.

Paul.

Actually, some of piano roll manufacturing methods are JUST like step-MIDI recording:


(Video shows real-time entry method as well... a good little vid!)

I don't think it would be practical to "tune on the fly". One of the keys to the system's accuracy is the fact that the strings are always sustained steadily at the same constant volume, both when recording the hand-tuning and when performing the automatic tuning. Striking a key causes a sudden spike in volume, followed by a gradual decay. There is actually a small difference in pitch between the loud and soft volumes. Louder tends to be sharper.

It is important for many reasons for a tech to tune striking firmly and softly and comparing harmonics between notes, etc. But when he's done, each string is sustained at a given volume and the fundamental is carefully measured. When the self-tuner sustains again when it tunes, it sustains at this same volume and the pitch is adjusted to precisely the same frequency as when the original hand-tuning was done.

It also makes the system simpler and faster, since the musician doesn't have to play through all the notes, one at a time, and wait for each to tune.

Hi Don,

Don't get me wrong, I think you're invention is brilliant! I was just thinking out loud here. You obviously know volumes more about what can and can't be done. Have you had any requests for your system to put the piano into various pythagorean tunings depending on what key a piece is being played in? I think your system would really shine here, as I understand that the way pianos are normally tuned is a bit of a compromise so that a piece will sound good in any key.

Don -

You said your first patent used a servo to tune the three unisons at once. Was it the expense of the servos and control boards that caused to to seek another method? Are very strong motors needed to be to handle the tension?

Actually, I did with an ordinary gearmotor. Here is the patent:

http://www.google.com/patents?id=bW4eAAA...ved=0CDQQ6AEwAA

It was slow and clumsy. The self-tuner is much simpler, faster and easier.

Took a quick look at the patent list. This is staggering - first filing date December 29, 1980.

You are a very patient man. I wish you all the good success in the world.

There are a few comments which are questioning or perhaps even a bit negative, but I personally think they are based on misunderstanding the physics principles involved so it would be neither prudent nor productive to address them.

I'm convinced this will work.

Can't wait to discuss with my technician/rebuilder friend - he is very open minded and will understand this concept immediately.

Glenn

Don,

You apply a dedicated current (voltage) to each string in the piano. The current is applied at the pinblock end of the string, flows through the string to the tail end, where the hitch-pin of the plate acts as "ground".

While the bridges are electrical insulators, the front termination of the speaking length is not. The strings are connected electrically at the front end, because the agraffes / V-bar / capo bar are all connected to the plate.

So, how do you control each string's current (voltage) separately if
... the two ends of each string are connected via the plate?
... the pinblock end of one string is connected with the next via agraffes, V-bar, capo bar etc.?

Does the plate not cause a short circuit across the string, and shunt currents from one string to the next?

If the cast iron is sufficiently conductive to act as "ground" at the tail end of the piano, why does it not short-circuit the front end of the strings?

Very good questions. In the text of the patent he says that the strings need to be isolated everywhere except at the hitch pins. So the agraffes and/or capo bar have to be changed to something else or modified? Won't that change the piano tone?

And if the agraffes have to be changed or altered, does that make installation to an existing piano more difficult?

Sam

Just getting back to the computer.

OK, first of all, I didn't start in 1980 (I was in high school then!). You were probably looking at some of the "prior art" dates. I developed the mechanical tuner in the late nineties, then the idea for the self-tuner came to me in about 2002. There has been a lot of development work since.

There are two basic ways to insulate the strings and I have done them both. Originally, I used plastic (Delrin) agraffes and string rests. This worked and the tone was unaffected, but it didn't hold up over time. I then went through a series of different agraffes including Garolite, bone, antler, brass with several different coatings including diamond, and several different designs that involved ceramic inserts.

The second way is to apply current at the hitch pin end. This requires the string to be split into two separate, independent strings (rather than just hooking around the pin). I did this with a brass anchor that slipped over the hitch pin and had two ceramic-insulated holes. The string passed through and then I crimped a bit of the end over against itself and silver-brazed it. This was like a knot to keep it from pulling back through the hole. Bass strings were strung with a small piece of Garolite tube slipped over each hitch pin and the string loop around that.

This way worked as well, but was not very practical for a field installation. I finally found a suitable agraffe material: PEEK (poly-ether-ether-ketone) that works great.

Ah, so there's more to it than installing the sensors, actuators and pinblock electrodes...

Interesting that you should end up with PEEK. I use a functionalised version of this material in my work, but for completely different applications (ion-conducting membrane with high thermal and chemical stability).

I find it interesting that your system can significantly change the tension of the strings by raising the temperature slightly, whereas the tension of the strings doesn't vary much when the room temperature changes. As someone said earlier, this is probably explained by the frame expanding to compensate for the strings' expansion.

But does this mean that if you were to enclose the piano in a thermally insulating box and turn it on for a long time, the frame would gradually heat up, prompting the system to heat the strings even more to maintain a temperature differential, causing the frame to heat even more and so on, leading to thermal runaway?

Of course nobody would put their piano in a box, but the thermal conductivity of wood is rather low so it might be a real issue when the lid is closed: it's not easy to get rid of 1000 W power (especially for smaller pianos), so in order to avoid reaching harmful temperatures is there a practical limit to how long the piano can be turned on?

http://www.gizmag.com/gilmore-self-tuning-piano-system/21425/

Hi Don,

Great article...I hope it's a go for you, and that you can have one for existing pianos at some point in the future. What I wouldn't give to have your system in my M&H Grand, along with the LX and Ampico...I could have concerts everyday and not worry about the piano going out of tune!

Looks like it is starting to evolve into something quite nice. I still do not understand how the device can increase the natural frequency of a string since apparently the only adjustment is to the amount of current flow, that is, there appears to be no way to increase the tension by cooling.

However, best of luck and I am looking forward to continued postings on your progress.

Mr. Gilmore:

Excellent!

I have an electrical/electronic background in addition to a piano tuning background and kept wondering how you would be able to apply the current to each string individually when they were electrically common at the upper termination and the hitch pin. You don’t explicitly say so, but it must be that only the upper, non-speaking lengths from the tuning pin to the upper termination is conducting individual currents. And just like in manual tuning, as this segment’s tension is changed, the string’s tension renders across the termination to the speaking length. I have to wonder what sort of algorithms you use, or might develop in the future, to deal with one of the most important parts of tuning, the rendering of the strings. It may shed light on what manual tuners do.

It does bother me a little bit when you keep referring to “5 volts” when it is really current that does the heating... But I agree that the tuning pin would see hardly any direct heating. No more than a very heavy extension cord would when plugging in an electric toaster.

Some of the arguments against the system are interesting but do not have merit:

The first has to do with resistance to losing employment in tuning pianos. Well, are piano tuners interested in servicing the piano or servicing the customer? I mean, isn’t having a piano stay in tune their job? Besides those that are tuning now will have plenty of ordinary pianos to tune for as long as they may tune. And those that may otherwise get into tuning would just find other employment. But then again, imagine John Q. Public walking into a showroom and listening to pianos that are all wonderfully in tune! There could very easily be a piano boom similar to when player pianos were first introduced.

Yes, the contact boards underneath the pinblock would be in the way when removing the action. But inserts and thumbscrews could make the contact boards easily removable.

Will an automatic tuning be as good as the real thing? Well if not as good as an hour old tuning, certainly better than a month old tuning! But with time and the right algorithms to deal with rendering, it just might be better.

And I see no reason that this system would not work on uprights as a retro-fit. The contact boards would simply be installed at the head of the pins.

I do wonder about the resonators affecting the tone of a fine piano, though. Anything added inside the piano does have some kind of muffling effect.

Anyway, I wish I had a few millions to invest in this. (Heck, I wish I had a few millions period!) Best of luck.

[Edit:] Oops, I didn't read all the pages and didn't know about the electrical insulation at the upper termination. But I am not so sure it is necessary. Without the insulation, only the upper non-speaking length would be heated. But as the string renders, it would need less and less current to change the tuning.

It would work as a retro-fit, but it wouldn't be a simple retrofit. If the piano has agraffes, then they have to be changed to something non-conductive, which means restringing the piano. If it's just a capo bar change like an upright, then all the strings have to at least be loosened so that electrically insulating material can be added.

So it's not as simple as just buying a kit and bolting it on.

Am I right, or am I totally confused? (Wouldn't be the first time).

Sam

AMEN!!!

Here's a self tuning guitar:
http://www.youtube.com/watch?v=6Qw1j2CLdwo&feature=related

Any long term effects from heated strings on the bridge, tuning pin torque, etc. ???