Theremin-guitar Idea

Hey,

I've got a cheap guitar that has virtually no use anymore so, trying to give it a new life I have been thinking of ways to make it a bit more interesting. I was thinking it would be pretty cool to route a strip down a portion of the back of the neck then install a theremin antenna into it then covering it with wood-filler to smoothen the neck out again and sanding back to shape. The rest of the system would be installed in the body of the guitar. I am completely new to theremins so only know a little bit of online theory. To my understanding the theremin forms a capacitor using your hand as a grounding plate. I therefore assume any other nearbly ground connections will interefere and give a sound. Other than this, are there any other issues I have overlooked?
Thanks!!

Hi tgalea, welcome to Theremin World. :-)

Theremin/guitar hybridisation is an idea that pops up quite regularly - hit the search link to see how my opinion of this has changed over time.

I'm not sure about burying your antenna under wood filler - it [i]might[/i] work once the filler has dried out completely if it is non-conductive. But there is a more fundamental problem if your intent is to play theremin and guitar simultaneously...

It's a common misconception that I see a lot when people first encounter a theremin - for some reason they seem to think that gliding your hand up and down the length of the pitch rod is a good idea. To be sure it is amusingly suggestive, but does little musically; giving a tone of fairly constant pitch. What changes the pitch of a theremin is how far your hand is away from the pitch rod - not whether it is near the top or the bottom of the rod. Embedding the antenna in the neck will ensure that your hand is a constant distance (very close) from the antenna. A constant high-pitch whine will ensue.

Here comes an assumption - that you're not looking to play a melody on the theremin - if you are, put your guitar away for a while and get y'self a moog etherwave for example.

So you're looking for something that is more rhythmic than melodic, with a healthy dollop of f*ckedupness to boot. Cool.

The best arrangement I have seen (courtesy of Mark E Pitt of Not Rocket Science) is mounting a short one-stick theremin into the body, not the neck, with the rod sticking out at right angles, so that it reacts to the movement of your strumming.

Even better is to ring-modulate the sound of the theremin against the sound of the guitar. It's the sort of sound that puts the mental in experimental.

Or get one of those little pitch to midi boxes and use the midi output to control a band pass filter for example. (And yell "SpeedWah!" from time to time while you're playing.)

Or, to avoid doing woodwork on your guitar, just stand a funky little one-stick theremin on a mic-stand nearby and play it with the head of your guitar by swaying rhythmically like The Shadows (http://youtu.be/_GTPyVmkKpo). (The dorky grin is optional.)

Thanks for the reply! You're correct that the plan is more for interesting sounds than playing proper molodies. As for the sound I was considering using a metal plate on the body as a volume antenna placing it where my arm usually rests. This direct contact would (to my understanding) mean that there was no sound from the theremin unless I moved this (my strumming) arm away from the guitar body. Other than that I planned to use it fairly seperate from the guitar maybe doing some pick slides with my strumming hand while using the other hand to waft around the neck creating the wonderful theremin sound! Does this use of the volume control and such make sense? Sorry, complete novice to the theremin world!

P.S. Shall get working on that grin!!

OK, I'm starting to get the picture.

Well, pitch [i]and[/i] volume sensors are [i]theoretically[/i] possible, but I've never seen it done on a guitar. It is deffo going to punch up the cost and complexity. TW's electronics wizards are probably nodding their heads solemnly by now. The short form is: theremins have to be ultra-sensitive to tiny environmental changes (your hand movements) which makes them pernickety by design.

In an ideal world you could pick up a cheap pitch-only theremin (for example: http://theremaniacs.com/ (*)) and a cheap volume-only theremin (no such beast :-( (**)) and Bob would be your uncle, but unless they were carefully tuned to not interfere with each other they wouldn't play nice together.

(*) Theremaniacs. I thought of this one not because of the words on the website - for all I know that could be pure advertising fluff, but because I like the audio and video clips at the bottom of the second page, and because you can buy it without an enclosure for fifty quid.

(**) No such beast. Well, there is this: http://zvex.com/trem.html but almost two hundred quid ain't cheap.

I would suggest, rather than a capacitive volume sensor, mount a kill switch on the body of the guitar and augment it with a volume treadle if you want. Check out Taubman's Electronde to see how this works out in practice. http://youtu.be/6HSH7OTgt4U


P.S. You are going to have so much fun feeding it through all your guitar effects pedals. I do that quite a lot. ;-) http://www.youtube.com/gordoncharlton

There is also this experiment where the strings of the guitar actually become the antenna:

Guitar Theremin (http://www.youtube.com/watch?v=LuvI-_0Zwno)

I don't think an instrument of this sort would be any use for anything except fun.

Believe it or not....IT WORKED!!! Using basically the idea I started with but the theremaniacs pitch only theremin (thanks to suggestion) I can now play guitar, theremin or a odd combination of both at the same time!! I've also added a series of controls for playability and its really great fun :) Thanks for the advice guys!

Great. Video required...

Maybe soon, still doing some minor tweaks to get it perfect

If possible, could you write a detailed report about your proceedings and tweaks? I'm sure that other TW members will be inspired by that!

Hello, I stumbled on this while I was searching for more ideas to upgrade my Git-o-min.

At the moment I am trying to make it a more playable guitar instrument with the theremin giving an added element.

My design is purely functional, the guitar was destroyed in my last gig with The Flaming Spastics (we supported John Ottway so all our instruments got sacrificed to try and upstage him!), the headstock was broke and the lower horn on the body snapped off (its a single cutaway gibson shape originally). So I cleaned up the head by putting a hard bridge next to the nut so it could be strung 'backwards', I cut a shelf in the lower body behind the bridge to facilitate grover tuning pegs and threaded the shafts through the body.

For the theremin part I use a No1derland single aerial mini-theremin, its small, works on 9v batter and only has a pitch aerial. This is perfect for my needs. I cut a reactangular space where the broken cutaway was to facilitate the theremin, I rigged a short right angle phono lead into the pickup circuit so it clips into the unit so sound is then mixed with the guitar output. Along the edges I used velcro so the unit can be still used as a stand-alone theremin, this also helps with changing the battery and playing position.

Playing wise it works well by either sweeping your hand as Gordon said earlier when strumming strings, another way is as you pick solo strings rest your hand on the body and you can roll your hand towards the aerial also getting an effect.

For now I am going to put a Floyd Rose style locking nut to try and stablise the tuning, truss rod is getting readjusted, new bridge arrangement and the electronics will be tidyied up. When I have done it I will post some pictures of my progress ;)