Special Project! Need a Theremin with a big radius of sensitivity and MIDI output!

Open Theremin V3 or V4 has a reasonable field if you want to play music with it but it is not that sensitive at a 8 feet distance...

A continuous pitch nulling (like in D-Lev's sculpture mode) would be required for sure. The automatic calibration involves some external component that are set through a "trial and error" process which is activated when you push a button. Making it continuous would require some important changes in the program structure, maybe a project on its own...

The MIDI version of the software can do plenty of things. Depending on the function you want, I can probably provide some support. 

This is too funny!For the translation:We live in a time where intelligent people are being silenced so that stupid people won't be offended.

I was hoping this would be a place without juvenile memes and dogmatic attitudes.  "Smart" comes in many flavors, and more often than not I am disappointed to find my technically minded friends deeply lacking in social and spiritual development.  This is a kind of myopic and dogmatic issue we all too often see in engineers and scientists. Hence we see engineers struggle to understand why their work is unappreciated by their user base, overlooking the fundamental human experience.  I generally chalk this up to things like isolation, social trauma, bad parenting, and even autism. It just never ceases to amaze me that process-minded adults never consider this worth learning about.  The first quote is an unattributed meme.  Why put it to Denzel?  I also read a lot of Einstein. He was quite the humanist, and I believe he would be dismayed to see his visage used alongside a statement as crude and silly. I don't think he would have ever said this. Are you in the age range of 10-14?

Not being a native speaker, it's hard for me to judge the presence of rudeness, but everything Christopher said was on point and correct.1. The teremin is not designed for the kind of tasks you suggest, and Christopher offers an adequate alternative.2. It is sacrilege to use a termenvox for anything other than music. It's like asking violinists on a specialized forum how best to scare cats with a violin.And I'd also add that Christopher has been around for a very long time and has a lot of experience.

I respect your skill and love your enthusiasm.  But it's my understanding that Theremin discovered this phenomenon whilst trying to invent a burglar alarm.  Is that inaccurate?  I came to this forum instead of an industrial capacitive sensor manufacturer  because I simply love my teremenvox.  I find its elegance and history would fit this particular art project well if I can integrate it.  Other sensors are boring and pedestrian.  I'm seeking to do something special with a bit of grace and mystery.  It may not work as desired, but I will learn some things and adapt my thinking in the process.  Is this not the scientific and dare I say human journey?  We must begin at a place of not knowing and leap into investigation.  If we are comparing intellect, education, wrote memory, and experience, are we not trapped in a mythology of egotism and insecurity?  I prefer to continue my investigation and see where it leads, especially if it fails.

Personally I've come to think that the different origin stories about the invention of the theremin might all me more myth than history. Theremin being a radio officer and setting up a few transmission stations for the army must have familiarized him with the heterodyne effect, when a regenerative receiver started to oscillate by itself and cause a howling sound. Similar to Maurice Martenot, who because of his trying to make music with the radio equipment, being fascinated by the heterodyne sound, was called "le chien Mexicain" (the Mexican Dog). In Dutch this kind of radio interference is called "de Mexicaanse hond" (wich also translates to the Mexican dog). The stories about the burglar alarm and the apparatus to measure the densities of gasses, that must have all been after encountering the heterodyne effect. It was cool how Leon Theremin went about to find multiple applications for what in the radio world was regarded as an error condition. Leon Theremin might also have been aware of Lee De Forest's concept of the audion piano and his description of how physical proximity and touching parts of the circuit (so Lee De Forest also invented circuit bending avant la lettre) would influence the sound. De Forest didn't complete his idea of the instrument but I think he did make some (partial) prototypes that he experimented with himself.

I think a theremin circuit could work in the setting of reacting to the presence and proximity of spectators, the circuit just needs to be tuned differently than for playing music on it by a thereminist. What you want is that the zero beat point/zone is some meters around the pitch antenna instead of being aproximately 60 cm from the antenna. With a theremin that doesn't lock the oscilators beyond the zero beat, the field inverses and the pitch goes up again after passing the zero beat zone.

Dominik Bednarz (Subscope.de) has also used theremin circuits as part of his kinetic art installations, that might have even be the thing that got him into building theremins in the first place, I'm not sure.

To help get this thread off of a lifesaving feeding tube . . . three well informed theremin researchers said what the original poster is trying to do is not something by nature that the Theremin Phenomenon can do, only in juvenile fantasy.

Two people that have a theremin product to "sell" know that the theremin won’t work well outside of 18” for a controlled unimaginable 5’ to 8’ or 1.5 to 2.5 meters but are still encouraging this failed approach, why? 

The OP is at risk of destroying a working theremin to learn the approach does not work for his need.

An alternative was suggested that the intelligence of the OP interpreted as using space lasers. 

This explains why this thread became stupid?

As I said, I do wish you the best of success.

"I was hoping this would be a place without juvenile memes and dogmatic attitudes."  - JSPorter

Ah, you've met our resident troll.  The tiresome thread derailing memes are likely being used to track your IP address.

Theoretical papers on capacitance often dispense with absolute dimensions because capacitance scales geometrically.  So a large enough plate with a large enough high Q inductor should be able to easily detect a human body more than a meter away.  One paper described a system of capacitance sensors to determine human occupancy and movement in a room, and it used lowly 555 timers for oscillators, along with a boatload of averaging and other methods for noise & drift reduction.  Not "selling" anything here: the D-Lev detects my body movements out past 1.5 meters, but when you get that far out you're in the femto-Farad measuring business, where things like flaky grounds and external interference (as well as internal interference like power supply noise, etc.) tend to place limits on the whole endeavor.

An Etherwave could probably be adapted to this sort of thing, but it would take some work.  Extra circuitry would be needed to buffer the oscillators in order to prevent lock around null (this is easy), but also to maintain null long-term without overly intruding on the operation (this isn't so easy as it involves frequency measurement and some sort of bi-modal filter).