Subscope Theremin

Posted: 2/7/2018 8:51:56 PM

From: germany, kiel

Joined: 5/10/2007

JPascal: maybe. Theoretically. But i cannot tell about a 'AHA' difference of behaviour to the normal rod.

Dewster: i am feeling honored, thanks. Unfortunately, whenever i have been asked about solutions and indeed answered or have given away schematics i felt not so good afterwards. I think because it takes that much time for me (who is more into arts than into understanding electronics ~ which i do not understand but: the route is the goal) developing|adapting circuit details (being them a little fancy or nothing but common) and hopp: away..

You were not asking for something to just copy but for a tip. If only i could.. give me some time..

Sensitivity, linearity.. i cannot provide you with data. It behaves like in the videos :) and yes for the EQ coil.

That book would contain more pictures than words. 

Posted: 2/9/2018 6:19:45 PM

From: Berlin Germany

Joined: 4/27/2016

Dominik: This theremin seems to be in design, handling, sound and dynamic one of the bests. I think, tips are welcome, secrets shall not disclosed. For me is your instrument a high level benchmark. May be you are creative and others are business minded. 

Posted: 4/5/2018 3:17:41 PM

From: germany, kiel

Joined: 5/10/2007

Dominik, I've been trying to implement the pizzicato volume thing you demonstrate above with some success, but I haven't been able to get it to a point that I'm happy with.  You're almost certainly doing it on the exponential side of things, and I'm trying to do it on the linear side.  I differentiate the signal to get velocity, only take positive differences (rectify), scale it (strength knob), and then present this to a leaky accumulator, the leak of which gives the decay (rate knob).  It works and everything, but I find that I can "pump up" the accumulator with repeated quick movements of my hand, which I don't like because it temporarily moves the audible threshold around.  Does yours display this kind of behavior?  Are you rectifying velocity?  Any tips you might give me?

it's been a while. And since then you have changed the behaviour of your theremins velocity feature. See here (also interesting videos below that posting).

At least our approaches are different. You seem to be using a specific hands location and a given speed to then trigger attack and decay events with a corresponding max amplitude. Behind that trigger point the normal playing zone starts. So your machine doubles in a theredrum and a theremin :-)

From your posting 1400:

You don't want to have to flick your hand quickly (velocity threshold) to have the envelope generator kick in, you instead want to merely move your hand past fixed positional threshold in space to trigger it, and use the velocity at the crossing to set the attack amplitude.  The position will necessarily be outside the normal playing field (or inside it if you have it set for farther = louder), and you don't want velocity kicking in when you're playing normally, so I believe this is the best approach all around.  Yarg...

Well, if velocity quite generally was a feature.. i think you might want to flick your hand quickly and you might want velocity when playing normal. Because exactly this is what theremin players already do even without a velocity feature. The movements simply follow the players intention. While playing any faster attacks might be comfortable with velocity.

I am not using a trigger to start events, it reacts sort of dynamically. I think it is much simpler than your solution. One possible model (i could be very wrong here.. and i am shure this is not smart):
- let A be the control voltage corresponding to the volume hands position.
- let B follow that voltage, but delayed. Like B'new=B'old+(A-B'old)/2
- A/B'new gives a multiplier to somehow generate the velocity voltage
- *ding*

Don't get me wrong. Your solution is interesting and those supersharp attacks are nice, but one would have to adapt. But there are some unused bits and bytes i guess.

A short video.

Posted: 4/5/2018 3:21:50 PM

From: germany, kiel

Joined: 5/10/2007

Dominik: This theremin seems to be in design, handling, sound and dynamic one of the bests. I think, tips are welcome, secrets shall not disclosed. For me is your instrument a high level benchmark. May be you are creative and others are business minded.

JPascal, thanks!

Posted: 4/8/2018 11:41:25 PM

From: Tucson, AZ USA

Joined: 2/26/2011

Hello Dominik,

Velocity is the word, never knew what to call it but in some of my theremin experiments I used that classic 555 to do a similar simple volume control technique. If the velocity pot was adjusted one way the slower hand movement or voltage rise on the pin 2 that triggered the 555 would bleed off before triggering the output. You then have the normal volume control in a slower volume control window. Higher hand speed would trigger the 555 so the sound would snap off or on, whichever was preferred. Also in my design the outer edge of the volume control window was more aggressive than near the loop for excellent soft sound control. Never had a qualified Thereminst test out my stuff so retired most of it.

D you also have a nice sound, must be analog? Not a che.. ......  .......


Posted: 2/2/2020 12:32:58 PM

From: Praha, Czech Republic

Joined: 7/10/2005

This is a very useful thread and I thank the entire congregation.

I have a query.

I am counseling a young Russian woman, a fine classical pianist, who somehow fell in love with my humble Burns B3 theremin. Her professor in St. Petersburg actually knew Lev Termen, to which I say wow. Though I quietly mention that I met Mr. Theremin during his US tour in the early 1990s. 

Anyway, now she wants to obtain a theremin. Since she's a real musician, I want to advise her on what's both good enough for a real musician while also being the most affordable (funds are limited). She lives in Europe, so some local purchase options are also scant.

Decent linearity is a priority, since my B3 cannot claim as such.

My research concluded that the Moog Standard is probably the best option in the affordable theremin category, and the Moog Theremini is an option even though purists might disagree.

So my query:
Is the Moog Standard indeed a good basic choice for professional play?
Does the Mood Theremini have decent linearity? Is there any concern that it's more of a digital synthesizer, with all those bells and whistles?
Are any of the Subscope theremins anywhere near the price range of the Moog Standard? (I assume they have good linearity, yes?)

Etherly yours,
Rev. Feedback

Posted: 2/2/2020 4:06:40 PM

From: Minnesota USA

Joined: 11/27/2015

You should contact Dominic Bednarz either by personal message here or through his website if you are interested in learning more about what he offers. I am not aware if he publishes any prices, but he seems to have a pretty defined price structure for the different models and options if you ask. 

Dominic built a custom Subscope for me after I had been playing an Etherwave Plus for about a year, and it was my favorite theremin until recently.  It had some really nice features and a somewhat different range of voices from those of the EW.

Being custom built though, it will be more expensive than the EW, and since it has more knobs it could be considered a touch more intimidating to start on.  Since the EW is so widely available new and used, it would probably be the least expensive instrument that would be suitable for a musician.  That said, I would highly recommend the Subscope as an instrument to move into later.

Regarding linearity, the Subscope and the EW have quite similar linearities at the mid- to high-end if you play with a Caroline Eyck style of open-closed hand fingering. Other playing styles may show some differences between the two, but for simplicity I would say that neither is better than the other in all cases.  Both compress slightly at the high end compared to the mid range.  The stock Subscope has a much more linear bass range down to zero-beat, where the EW tends to compress a bit and lock up near zero beat.  But many people have Thierry Frenkel's ESPE01 mod or something similar installed that greatly extends the range into the lower octaves while also improving some of the harshness of the sound.  A well-tuned EW can have very good linearity and a pretty good size pitch field that doesn't feel cramped at higher pitches.

Another thing that I really like about the Subscope is a telescoping brass tube that slides over the pitch antenna for making large (sometimes seasonal) adjustments to keep the pitch knob range centered.  This allows coarse, less frequent adjustments to be made with the slider while allowing the pitch knob on the front panel to perform as a finer adjustment.  By contrast, the pitch knob on the EW covers a wider tuning range to be able to reach proper tuning with the natural variations that occur over time or with changes in humidity, but this wider range means that the control can be overly sensitive to adjust day to day.  And even with the wider range the EW can sometimes go out of tune beyond the range of the knob and require removal of the cover and adjustment of the internal inductors to recenter the tuning of the front panel knob.  It is possible to make an antenna slider for the Etherwave as well that will in may cases prevent having to go inside the cabinet to retune, although without modification the pitch knob will still remain touchy.  And there are actually more variables to consider for keeping any analog theremin optimized other than simply keep the pitch knob tuning within range.

Short answer:  An Etherwave Standard or Plus is an inexpensive and quality product that is good for starting on as well as for playing professionally.  There will always be other theremins out there to expand into later. Others will have to offer opinions on the Theremini, but my impression is that you may be better off going directly to an Etherwave.

Posted: 2/3/2020 6:33:56 PM

From: earth

Joined: 5/8/2017


Harrison Instruments Model 302  - 8 octave range, 9v battery operated, plate antennas make for easy and steady play, inverse volume mapping makes staccato play easy and pizzicato possible. Affordable. Concerning linearity - just aim for the corner of the plate and that stretches out the upper range, but hey 9 octaves without flipping any switches.

Arthur demonstrating the 302 at Chuck Leven's

opening the model 302

Me playing the 302 with a few pedals

Posted: 2/3/2020 7:23:23 PM

From: Portland, Oregon

Joined: 2/22/2018

I'll just say on the issue of cost: Theremins are cheap compared to most musical instruments. On the occasions when an Etherwave Pro becomes available and people get sticker shock that it sells for $5-8k, that's actually within the range that an advanced amateur (not even professional) violin or cello player might expect to pay for a high quality instrument.  Professional string players might pay more - sometimes much more.  rev.f mentions a friend who plays piano - what kind of piano can one get for less than $1000?

If you don't have the money you don't have it, I get it, but really on the issue of cost we thereminists have little to complain about.

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