Let's Design and Build a (mostly) Digital Theremin!

Posted: 3/16/2022 10:21:18 PM

From: Northern NJ, USA

Joined: 2/17/2012

"D-Lev's linearity is a kind of comfort zone. With a D-LEV properly tuned, the Theremin suddenly becomes easy to play, which is good.  As an average player, I am happy because I can focus on the music and not on how to deal with non-linearity."  - Mr_Dham

Yes, I'm the same.  And I wouldn't be even thinking about it, but there are lots of folks out there who are highly acclimated to analog fields.

"Anyway, one could look at the problem in the opposit way: after a certain time, will I be able to use another theremin?  But this can be resolved by playing an analog theremin from time to time in order to develop appropriate flexibility."

Agree, although the D-Lev might be their only Theremin.

"BTW, Is there two analogue theremin with same linearity and pitch response ?"

Excellent point, what is the target?  Bass coupling aside, all non-EQed analog Theremins have identical pitch non-linearity, but that's about it.

"That said, voulume "drop" is very helpfull in "higher-louder" volume mode in oder to reach silence before touching the plate."

I find it useful it even in the closer=louder volume mode.

"Pitch "lift" would help to copy the effect of frequency that looks like going to infinite when reaching the antenna (I have it on my "no serial inductance" theremax). I used it as an effect but it never helped me for playing music precisely."

I implemented and am playing around with various combinations of analog mode and Drop / Lift on the fields.  I was kinda sorta hoping analog mode would win overall (and make ME blameless too!) but I think Drop is more useful on the volume side because it can be used to enhance the quiet zone with closer=louder as well (but I repeat myself).  And Drop doesn't require the hand to be near the antenna to go non-linear.

I'm a little torn between Lift and analog mode on the pitch side.  Analog mode is certainly authentically non-linear near the antenna, but with Lift the strength of this can be dialed in, which might get one closer to both EQed and non-EQed instruments.  And Lift doesn't mess with the linearity of the far-field, which I think is important too.

I don't think players really care about the "analog authenticity" of the volume side, they mainly want something that works with their style.  Volume responses tend to be all over the place anyway.

So, "blameless" is great goal and all, but I believe utilizing the natural non-linearity of the analog response is probably not an ideal situation for the pitch nor the volume fields in a linearized instrument.  One should linearize first, and then deviate from this with various polynomials.

Posted: 3/20/2022 9:45:38 PM

From: Northern NJ, USA

Joined: 2/17/2012

Employee Of The Month

Here at D-Lev Worldwide Industries, we pride ourselves that our employees are granted full flex time benefits  - which means they have the complete freedom to pick any 80 hours a week they want to work. ;-)

Above: 28 AFE boards all soldered up and tested.  Several wouldn't oscillate without me putting my hand near the antenna, and I traced this back to a different batch of 74AHC04 hex buffer ICs, which presumably have stronger hysteresis (was waiting for that one to bite me).

A jumble of 15 AFE & coil boxes waiting to be assembled.  Need to print another batch once the box clamps are done.  I'm really digging the translucent blue PETG, quite iridescent!

10 control panels and 14 tuner assemblies.  The tuners have been tested but the controllers haven't yet (3 are off camera, and I need to print one more to finally update / overhaul my lab unit).

The corrugated plastic panels have been cut to size and the necessary holes have been poked in them via various soldering irons (heat is generally your friend when it comes to plastics).  The logo plates have been painted but need sanding. 

The shipping department is gearing up for action!

Posted: 3/22/2022 4:58:29 AM

From: Minnesota

Joined: 3/9/2013


Posted: 3/27/2022 12:22:39 PM

From: Northern NJ, USA

Joined: 2/17/2012

Video Nasty

New sleazy video posted: https://www.youtube.com/watch?v=O7Bb-TnZVIY

15 precious minutes of your life will disappear forever as I hector and drone on about the ACAL, the whole ACAL, and nothing but the ACAL.

Posted: 3/27/2022 6:12:49 PM

From: Northern NJ, USA

Joined: 2/17/2012

Flamma Lama Ding Dong

Since the D-Lev resonator will only sorta do ambience, after discussions with a kit owner I picked up this fairly inexpensive pedal to do deep reverbs and such (he bought one too):

Here's a sample: https://d-lev.com/audio/2022-03-27_flamma.mp3.  This thing will get huge!  Like totally lost-in-space, far out man huge.

One slightly odd thing about it is each preset slot also selects the particular algorithm, so e.g. you can only save one "cave" preset in the "cave" preset slot (#4).  I wish the room size was a knob because I often like that little room sound, and this thing only gets but so small sounding.  True stereo I/O though, which is important because the D-Lev has (pseudo) stereo out.

Posted: 3/29/2022 1:46:15 PM

From: Northern NJ, USA

Joined: 2/17/2012

D-Lev Sighting: Rob Schwimmer

Yesterday evening the amazing Rob Schwimmer masterfully played the piano, his Haken Continuum and ondioline - and his P3!  You can stream it for the next few days here (if you enjoy it please consider tossing them a few buckaroo banzais):


Photo courtesy of Rob Schwimmer

Posted: 3/29/2022 3:51:51 PM

From: Porto, Portugal

Joined: 3/16/2017

D-Lev looks cool

Posted: 3/30/2022 1:58:49 PM

From: Northern NJ, USA

Joined: 2/17/2012

Peter Becan's Suitcase Build

Last week local Thereminist Peter Becan dropped by to show me his spiffy suitcase build for the D-Lev kit:

Top: controls & display folded up for action; bottom: controls & display folded for travel.

Peter had the plastic face pieces custom cut and drilled, and he bent them himself (very carefully!) using a hot wire jig, ala the way Roger bent the P3 acrylic panels.  Scary stuff!

There's a complex hinge on the control panel that took a fair amount of design effort, you can see it in action here: https://youtu.be/WdOCceTTY6o

The hole at the upper left is where the floor box unit is stored during travel (not shown here).  It contains the power supply, DAC, and footswitch jacks.

The hinge pins are removable so the top comes off with a little bit of work.  Peter is going to mount a microphone stand in the middle of the top, and rest the bottom on it for playing, which should work out well because the outer faces of the case are designed to interlock a bit to facilitate stacking of one on the other.

Peter is still contemplating how to mount the pitch and volume plates.  He had some transparent front and back panels made with similar dimensions to the temporary cardboard ones provided in the kit.  I gave him a few UHF connectors to think about as possible candidates here as they are rugged both mechanically and electrically, and will accept a banana jack too, so they are quite versatile.

It's always a pleasure visiting with Peter, and I want to thank him for sharing his beautiful build with us!

Posted: 3/30/2022 5:06:55 PM

From: Portland, Oregon

Joined: 2/22/2018

D-Lev Sighting: Rob SchwimmerYesterday evening the amazing Rob Schwimmer masterfully played the piano, his Haken Continuum and ondioline - and his P3!  You can stream it for the next few days here (if you enjoy it please consider tossing them a few buckaroo banzais):https://www.soapboxgallery.org/live-streamPhoto courtesy of Rob Schwimmer

Good show! Schwimmer's a great musician to showcase the D-Lev

Posted: 3/30/2022 6:33:05 PM

From: Northern NJ, USA

Joined: 2/17/2012

"D-Lev looks cool "  - Buggins

"Good show! Schwimmer's a great musician to showcase the D-Lev"  - bendra

I wonder if anyone could tell that it was a D-Lev?

You must be logged in to post a reply. Please log in or register for a new account.