Intentional Interference?

Posted: 7/2/2019 9:53:18 AM
luxxnatura

Joined: 7/2/2019

Hi all,
I dont have a theremin, but I am conducting academic research that points a little in this direction. I wonder if there is a way to intentional interfere with the electromagnetic field of the theremin? For example, if you were to place a copper plate or similar near the antenna, would it sound different than if it were a human hand? What are the glitch possibilities here?

Thoughts?

- Luxxnatura

Posted: 7/2/2019 1:34:30 PM
DreadVox

From: The Lower Lands (East)

Joined: 6/18/2019

Hi Luxxnatura,
a conducting object within the reach of the pitch field will only produce a steady pitch and change the geometry of the field to some extent. If the object would move (like something positioned off-center on a rotating record player) or vibrate, this would modulate the property of the antenna it influences (AM for the volume antenna, FM for the pitch antenna). A nearby plasma globe or tesla-coil can interfere with the fields around the antennae, too close could be risky and possibly fry sensitive components in a (solid state) theremin without explicit ESD protection, wich means most/all commercially available models.

Touching the volume loop antenna/plate can cause glitchy sounds, for solid state theremins that don't have ESD protection there is some risk of frying something inside, if one's body has an electrostatic charge, so it's a good idea when one is going to touch the metal of one of the antennae, to touch a screw that connects to the chassis or other point that represents earth/ground on the theremin or in the connected amplification chain, or to put sufficient isolating material around the bare metal (electrical isolation tape, PVC/silicone tubing/shrinkwrap) where one intends to touch it.

Posted: 7/2/2019 3:18:57 PM
oldtemecula

From: 60 Miles North of San Diego, CA

Joined: 10/1/2014


lux & Dread you two have very refreshing thinking. Here is a theremin sound I generated 20 years ago and abandoned it because the method was too freaky and the digital people said it could be done (any sound) easily in digital. Then they showed up with the Theremini 10 years later. Never experimented with a Theremini so wonder what magic they can do with that.  Angel of Death.wav 

My Pitch antenna has a DC resistance of 5 ohms directly to ground and my volume loop is protected with 40kv wire as seen below.

My own research benefits using the EWS wood box so I am happy it was engineered or designed with the fatal static flaws. visit  Hwy79.com

Christopher   


Posted: 7/2/2019 5:10:04 PM
dewster

From: Northern NJ, USA

Joined: 2/17/2012

"I dont have a theremin, but I am conducting academic research that points a little in this direction. I wonder if there is a way to intentional interfere with the electromagnetic field of the theremin?"  - luxxnatura

You certainly can interfere with the Theremin fields, unfortunately.  A high voltage oscillator operating nearby and at the same (or slightly different) frequency will disrupt things.  FM modulating it can reveal the gestural bandwidth of the response.  I believe you can also mess with the fields by modulating the Theremin ground, though I haven't tried this.  So the first approach is high impedance, the latter low impedance.

For example, if you were to place a copper plate or similar near the antenna, would it sound different than if it were a human hand?"

The "sound" or timber produced would be the same.  Capacitance is capacitance.

"What are the glitch possibilities here?"

I don't understand the question?

Posted: 7/2/2019 5:21:32 PM
rupertchappelle

From: earth

Joined: 5/8/2017

When I used the Etherwave, sometimes it just refused to be tuned, so placing a can, coin or some metal object on the Etherwave case would make things workable. Also attaching tinfoil to the antenna would also adjust the pitch field. Finally I started using a spring antenna that I could stretch or compress depending on the vagaries  of the pitch field.

So, objects are passive unless you have one rotating for vibrato - very doable.

To interfere with the theremin, a strong radio broadcast cuts through occasionally but the most reliable external source for messing up your waveforms is another theremin - close by, preferably being played Two humans play and the two theremins produce "enhancements" not unlike a ring mod sound. ?Not all pairings will produce this effect. Arthur and I have theremins that do not interfere, because Arthur.

What you really want are guitar pedals. Effects are controllable and repeatable.

Mel9 - mellotron it. Strings, vocals and sweetness and everything pretty.
WMD Geiger Counter - yeah, that's the ticket for you! that should ugly things up swell.

I use both of those pedals for "National Electrophonic" on youtube.

But you do not have a theremin . . . you don't want a theremin that is easy to play, no one does. I prefer an easy instrument to play that I don't have to use vibrato with and can play staccato as well as legato.

so you buy whatever everyone else buys because I don't relish any competition.

And remember PRACTICE, PRACTICE, PRACTICE 

Something I would never do. I just play.

Posted: 7/2/2019 5:25:15 PM
rupertchappelle

From: earth

Joined: 5/8/2017

Dewster:

[color=#008e02]"What are the glitch possibilities here?"[/color]

I don't understand the question?

Remember traveling in a car late at night listening to the AM radio in the middle of nowhere and the stations fade and cross fade with each other and static???
Why don't they make a pedal for that?

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