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

Posted: 1/14/2020 3:32:11 PM
dewster

From: Northern NJ, USA

Joined: 2/17/2012

"Your playing skills are getting better." - Buggins

Thanks for the atta-boy!  I think my pitch control is finally getting back to where I was a couple of months ago, though it was never all that great in the first place.  I need a more portable D-Lev for vacations and stuff, I'm too early into learning to not seriously backslide during breaks.

"Could you pleas share list of songs you already found?"

Here's a list I keep printed out and in front of me at the Theremin.  Most, but not all, are easy for me to play.  When I don't know the key I usually go with C/Am as I can see that easiest on the LED tuner, though that sometimes sounds weird for the range of a given voice.  I've uploaded recordings of most here at TW:

Key/Start  Title
C/C  Ave Maria
Ab/C Pie Jesu
C/G  Amazing Grace
C/G  Motherless Child
C/G  The Sound Of Music
Gm/A Speak Softly Love
C/C  Over The Rainbow
Bm/B Love Is Blue
C/G  Swanee River
C/B  Danny Boy
C/G  Star Spangled Banner
C/G  Daisy
F/C  He Shall Feed His Flock
D/F# If I Only Had A Brain
D/A  Whistle While You Work
C/E  The First Noel
Dm/D God Rest Ye Merry Gentlemen
Em/E O Come Emanuel
C/C  It Came Upon a Midnight Clear
C/G  Alfie
C/C  What’ll I Do
C/A  The Shadow of Your Smile

One of the real dangers for me is thinking I know a song and playing it for a while, then finding out I was playing certain notes wrong, leaving out whole sections, etc.  It's really easy to reinforce bad memory to the point where I almost can't unlearn it.

Posted: 1/14/2020 6:33:35 PM
Buggins

From: Theremin Motherland

Joined: 3/16/2017

It's really easy to reinforce bad memory to the point where I almost can't unlearn it.

Playing in parallel with original (10-100 times) might help (probably).

Key / starting note information is really useful for theremin playlists (in presence of tuner)


I notice that while playing, I think I'm very close to proper notes. But hearing of recorded shows how far I'm from ideal performance


Posted: 1/16/2020 3:30:42 PM
dewster

From: Northern NJ, USA

Joined: 2/17/2012

"Playing in parallel with original (10-100 times) might help (probably).
Key / starting note information is really useful for theremin playlists (in presence of tuner)"  - Buggins

Yes, I should be more fastidious with my practice, I suppose I've always been lazy about that on every instrument I've ever tried to play. 

The key / starting note is really essential for me on the D-Lev, as I tend to learn things by watching the tuner.

Posted: 1/16/2020 3:44:32 PM
dewster

From: Northern NJ, USA

Joined: 2/17/2012

Librarian Progress

After almost a month (yikes!) the librarian work is winding down.  It works fine in Linux Mint, but I need to port it to MSWin (eek!).  Here are the screens:


Above is the editor screen, where individual encoder values can be manipulated.  The +/- keys increment/decrement the highlighted encoder, or you can enter a number.


Above is the preset file directory listing.  Highlighting a file and hitting enter sticks the file name on the command line below for further manipulation with the various commands.  The highlight position will scroll the page so you can access as many preset files as there are in the directory.  This file list is also used for Tab-based autocomplete on the command line.


Above is the slots page with the default download.  You can view all the slots on the D-Lev this way, using the highlight scrolls them if they don't fit on the page, and the enter key loads them into the editor.


Above is the terminal mode, where you can interact with the D-Lev Hive processor via the HCL command language.  Here I've listed the first 16 Theremin registers (the top 4 nibbles of register 0 are the Hive firmware version, here: 0x1306), the version (last 4 bytes of the EEPROM SW load) and CRC (the CRC is calculated over the EEPROM SW load, and 0xdebb20e3 is the "good" signature).

And here are the commands:

Code:
COMMANDS:
- Command line return status: OK = successful; ? unsuccessful, followed by error
- The general format is parameters (if any) first, separated by spaces, 
  terminated by the command, followed by a white space (space, return, etc.)
- Preset file extension *.dlp automatically added / removed.
- "cla" on the F1 screen sets all encoders to 0.
- "r" refresh screen (and update directory listing but not slot listing).
- "quit" quit program.
- "help" display this file.
- file "delf" delete file (file mandatory).
- file file "renf" rename file (files mandatory).
- file "rf" read file (file optional).
- file "rsf" read system file (file optional).
- file "wf" write file (file optional).
- file "wsf" write system file (file optional).
- file "owf" overwrite file (file optional).
- file "owsf" overwrite system file (file optional).
- file "pf" print screen to text file (append, file optional).
- name "ren" change preset name in editor (name mandatory).
- slot "dl" download single slot, send to editor (slot mandatory).
- slot start slot end "dl" download array of slots (slots optional).
- slot file "dlf" download slot to file (slot & file mandatory).
- slot "ul" upload editor to slot (slot mandatory).
- file slot "ulf" upload file to slot (file & slot mandatory).
- slot "ed" previously downloaded slot data to editor (slot mandatory).
- filename.spi "pump" upload D-Lev SW load to EEPROM (file & ext. mandatory).

It has all the subroutines and such to upload and download all of the presets in a given D-Lev, and a command that can download them all, but no equivalent "upload them all" command, nor commands to save / load an entire bank to / from file.  I'll implement that once a few more changes are made to the D-Lev SW regarding the presets.

Posted: 1/16/2020 7:19:05 PM
tinkeringdude

From: Germany

Joined: 8/30/2014

Playing melodies you think you know, haha. I have excactly the same problem, just with singing. Hard to unlearn.
At least with singing one can learn it on piano first, and then practice to sing sync'ed to that, your hand positioning while playing also helping the singing, as you are clocking everything and can do "clock stretch" (vs. a play-along recording, where you are not) .
With theremin, your hands are virtually tied. And if hitting the right pitch is difficult, learning a song is more difficult. Maybe it's still helpful to learn it on another instrument where getting the correct intervals to memorize is "easy", and then play it on the pitch-challenged instrument.
At least as long as one can't play that instrument in one's sleep...


Posted: 1/18/2020 3:36:56 AM
dewster

From: Northern NJ, USA

Joined: 2/17/2012

"Maybe it's still helpful to learn it on another instrument where getting the correct intervals to memorize is "easy", and then play it on the pitch-challenged instrument."  - tinkeringdude

I don't mean to go on and on about it, mother's love etc., but the D-Lev tuner has made me more aware of absolute pitch and key more than any instrument I've ever "played" and in a fairly painless way.  With trumpet it was relative to b flat and fingering, so that wasn't a lot of grounding.  With guitar it's all relative to easy to play patterns that aren't all that absolute (particularly once you toss a capo into the mix).  Piano is all key of C/Am, so unless you're pretty trained the other keys and intervals are kinda foreign.  I don't think any instrument should be as biased to a key as piano is, though I suppose it gives you a base to notate from (along with a butt-ton of chord and scale variations to teach your spine).

Kelly Joe Phelps (a god among us) inspired me to butcher this one today: [MP3]. The ersatz dobro voice is interesting because it's a blend of attack and legato/vibrato decay.  You can sort of fake a "slide vibrato excited" longer decay sound with your left hand.

[EDIT] I encountered the "Eton Boating Song" tune first as the theme song (with much more subversive lyrics) to the movie "Society": [MP3].  IIRC the movie soundtrack has a really lame "General MIDI on a toy keyboard" type oompa/waltz accompaniment to the operatic singer.  This is maybe my 10th time through it (sorry!) but it's a simple and easy to play tune that's fairly recognizable (at least to some horror fans!).

Posted: 1/18/2020 11:03:27 AM
tinkeringdude

From: Germany

Joined: 8/30/2014

Piano is all key of C/Am, so unless you're pretty trained the other keys and intervals are kinda foreign.  I don't think any instrument should be as biased to a key as piano is, though I suppose it gives you a base to notate from (along with a butt-ton of chord and scale variations to teach your spine)

Ok, I totally agree with that. It's one major thing actually, that held me back from really committing to learn the piano. The whole note system based on that... because of a lack of ideas to uniformly layout stuff and still make notes identifiable, I presume, ugh...
I once found a pretty neat, and hundreds years old, "symmetrical" piano scheme,  no weird alterations of how many half tones are between two given keys, and it even managed to still kinda highlight the usual piano C key for orientation, to get used to. Alas I forgot the name of it. There were some youtube vids, can't find them. Some of the "big" keys where black, and some of the "small" ones white, in some alternating pattern, IIRC, but it's blurry. (but it was with regular key layout otherwise, not that weird stuff with multiple rows of keys or hexagonal things) There was a page explaining it in detail: Learning 2 shapes instead 12 for everything (or really just 1, which is shifted between starting with a big vs. small key). Wouldn't that be nice.
Obviously, it never took on. Perhaps once people are entrenched in a complex system and infrastructure of teaching between generations is in place, there's not enough appeal in a more logical system, the other stuff has too much weight.

But you're not "sorta on pitch" and in places maybe give your ear wrong impressions of intervals of a melody, you're dead-on with a keyboard, as far as equal temperament goes.[/color]

Posted: 1/18/2020 2:39:42 PM
dewster

From: Northern NJ, USA

Joined: 2/17/2012

"I once found a pretty neat, and hundreds years old, "symmetrical" piano scheme,  no weird alterations of how many half tones are between two given keys, and it even managed to still kinda highlight the usual piano C key for orientation, to get used to. Alas I forgot the name of it. There were some youtube vids, can't find them. Some of the "big" keys where black, and some of the "small" ones white, in some alternating pattern, IIRC, but it's blurry. (but it was with regular key layout otherwise, not that weird stuff with multiple rows of keys or hexagonal things) There was a page explaining it in detail: Learning 2 shapes instead 12 for everything (or really just 1, which is shifted between starting with a big vs. small key). Wouldn't that be nice."  - tinkeringdude

Would that be the "Balanced" AKA "6-6" or "Six-Six" keyboard?: http://balanced-keyboard.com/PeopleAndResources.aspx (god I love old school web sites!)

I like the idea implemented on this accordion, where three rows allow the player to learn just two major scale types (one for each hand if it were laying down horizontally to play like a piano), two major triads, etc. instead of four:

I had a cardboard prototype from years ago where I had a similar arrangement, but the keys were arranged on facets of a long flat prism, and you would hold it between your arms more or less vertically to play (imagine the accordionist above reaching his left hand over to play with the right hand).  With that arrangement one would only need to learn a single major scale, a single major triad, etc. as the hands are vertically symmetric (though of course they could get in the way of each other).

"Obviously, it never took on. Perhaps once people are entrenched in a complex system and infrastructure of teaching between generations is in place, there's not enough appeal in a more logical system, the other stuff has too much weight."

I feel in my bones that someone will do it though.  Make an instrument that is really easy to learn, fun to play, highly portable, and can be studied in a classical fashion.  It could be the next guitar (can you imagine walking into a Guitar Center and seeing your creation lining the walls?).  Stick a section of actuators at the bottom of the prism arrangement I described above for strumming and such:

The "Balanced" layout already packs an octave smaller than normal (good for the generally smaller hands of women and children - the bulk of the piano playing community!), but the keys could be made fairly thin with a lot of space in between (think monster guitar frets), which would enable one to pack even more keys into a smaller space without negatively impacting playability.  I think the "flattened prism" shape allows the player to better "feel" where they are on it, as opposed to an entirely flat keyboard, and it may allow the hand to be more relaxed when playing it too.  I would probably aim for as flat a prism as possible, while still being able to feel one's way around.  Also, you can do a chromatic slide on this by running a finger down either of the middle two prism corners, where all the key ends congregate (chromatic slides are really important IMO).

Posted: 1/19/2020 5:59:46 PM
tinkeringdude

From: Germany

Joined: 8/30/2014

Ah! Thanks. That page contained this link:
http://www.le-nouveau-clavier.fr/english/

Which was what I had originally stumbled upon.
And this:
https://www.youtube.com/watch?v=6fqMKI4AJwA

This looks like a CNC router project... Well, some guy just bought extra keys with the right parts missing to augment his MIDI keyboard to form this, but he has no black big keys. Made of wood... one could just wood stain and then a finish.

Posted: 1/20/2020 9:05:21 PM
dewster

From: Northern NJ, USA

Joined: 2/17/2012

tinkeringdude, those are fantastic links!  I've seen the first one before but it was really nice to read it over again, really clear train of thought as to ergonomics, why it hasn't caught on, etc.  And the videos are super interesting too.  Thanks!

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