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

Pongo

Cross compiling is fairly trivial with Go.  A short code snippet that reports open serial ports compiled on my Linux box ran fine on my Windows 10 laptop.  A Go implementation of Pong also ran OK-ish on Windows, but much better on Linux (the post XP Windows terminal is a total dog).  Go is very similar to C/C++ so maybe it won't take too much work to convert the D-Lev librarian functionality to Go code.

12TET

The 12 tone equally tempered system freakily amazingly maps simple frequency ratios almost perfectly to our logarithmic ears:

https://github.com/aguaviva/articles/blob/main/why_12_notes.ipynb

No wonder everyone pretty much abandoned other tunings when it was invented.  Call me crazy, but I kind of like the residual interbeating of the not quite exact ratios.  And you don't have to retune your piano (or buy a series of flutes, oboes, clarinets, etc.) to play in other keys.  It must have been a huge relief to early musicians, freeing them to explore higher levels of music.

Katica & Rob

Had the immense pleasure to have both Katica and Rob Schwimmer together at casa del dewster Wednesday:

They played standards, folk tunes, and generally jammed the house down!  Rob was absolutely fantastic (as usual) on the piano!  Katica played a mock-up D-Lev and Rob's P3, then switched to violin, a total master of both!  I'm still coming down from it all!

Great! There would be some space on the wall besides the painting showing exactly a still of that video.

"Great! There would be some space on the wall besides the painting showing exactly a still of that video."  - DOMINK

I should have asked Rob and Katica to pose like in the painting! ;-)

D-Lev Tour Kit Build

I just completed a build of the D-Lev kit components! You can read more about it here: https://d-lev.com/support/D-Lev_Tour_Kit_Build.pdf

New Command Line Librarian

The new command line based D-Lev librarian is now posted (on the D-Lev site Support page), along with slightly new software and almost all presets slightly edited to match. If you don't use pitch correction you probably don't need to do the update anytime soon. Anyway, I made some cheesy videos, updated the manual, quick reference, yadda, yadda.

Also wanted to mention that the OpenSCAD files I used for the Tour build (antenna mounts, mike stand trim ring, etc.) are now posted there as well.

https://youtu.be/hmMrWFP2QxE - intro, help, and port setup
https://youtu.be/_hpXTA81WH0 - view and slots commands
https://youtu.be/6mxakcC88Ig - ktof and ftok commands
https://youtu.be/mTUGFVOo7Jg - stof and ftos commands
https://youtu.be/8BbR_sDC4lM - stob and btos commands
https://youtu.be/-CnDFTUuMTg - dump and pump commands
https://youtu.be/-P931goMytE - update and factory reset

Boom Boom!

When Jeff was visiting at one point he was using a boom microphone stand that was smaller than normal, but not one of those ultra shrimpy deals that are only good for miking bass drums and such.  I asked him what make and model and he directed me to the Samson MK-10:

https://www.amazon.com/dp/B003CLIPHO

I ordered one and received it today.  Not the strongest thing in the world, particularly with plastic leg hinges, but it should work pretty well for holding almost any Theremin at sitting or standing height.  Quite inexpensive and lightweight too, and folds up fairly small to 640mm (25") long, would be great for busking, etc.

I cut the handle end of the boom pipe off, leaving a couple inches of pipe to grasp with a locking pliers.  Removing the plastic handle was fairly difficult, I tried boiling it in water, freezing it, and finally applying a scary amount of heat via a heat gun and torquing it with a soft rubber pipe wrench did the trick.  The pipe extends into the handle 50mm.

Top to bottom: The box, boom pipe I cut in two separate pieces, the resulting stand.

Then I cut off more of the pipe, a total of 440mm including the handle cut above, and left a little for in and out movement of the residual boom.  For the D-Lev tour I just built, one would angle the boom somewhat, and for EW, Theremini, etc. one would not angle it.  It's really handy having a handle to spin to thread the thing on rather than spinning the entire stand and/or the Theremin itself.

 
Left: Fully retracted, height is 650mm (25 1/2"); Right: fully extended, height is 1185mm (46 1/2").  I don't know why these heights aren't included in the product descriptions, they're fairly critical things!

Big thanks to Jeff for discovering this ultra rare intermediate height boom mike stand!

This is what I used for my wine box cabinet: https://www.amazon.com/LCD-Mount-Standard-Microphone-Stand/dp/B008I5QEP4

Works pretty well with a short mic stand and doesn't require any engineering. 

I also found this, which looked smaller/nicer and probably would have worked fine: https://www.camcor.com/cat/MIC-STAND-ADAPTER-FOR-MXA710-A710-MSA.html#

Nice bendra, thanks for those pointers!  I like the boom approach because it makes screwing and unscrewing the Theremin easier, but the downside is there is possible rotation about the boom axis.