DrooOone Circuits

[PHOBoS]

Recently egasimus asked how to make a common detune control for
multiple 40106 oscillators. One obvious thing that came to mind was
using vactrols. Of course the oscillators won't detune exactly the same
which can be very useful for creating droney sounds.

My initial idea was to take a PWM controlled 10mm LED and place 6 LDR's
around them controlling 6 oscillators (40106). I did some experiments and
eventually ended up with using only 2 vactrol controlled (or is that vactrolled ?!)
oscillators.

So here's the first circuit: "3240106 Droner"
- It has 2 oscillators to set a base drone one of which is slowly and slighty
modulated by a triangle wave provided by a third oscillator.

- Then there are the 2 vactrolled oscillators. The vactrols are driven by
a PWM controller which in turn is also modulated by a triangle wave.
Modulation depth and speed can be adjusted. The 100k trimpot is to set
the offset to get a nice vactrol responce. I made mine from a ordinary
5mm red LED, a LDR and a piece of heat-shrink tubing.

- The oscillators are passively mixed together using resistors and I added
a small cap to make the sound less harsh.

The enclosure is probably temporary as I'm planning to build a couple of
drone ciruits and put them together in a box with a mixer, delay, filter and
what else might be useful to create some nice drones (tips are welcome!)
I'm thinking of adding a cheap circuit bent keyboard aswell.

here's the schematic, a photo and some demos:

---

3240106 Droner.gif
Description:	PHOBoS - 3240106 Droner schematic
Filesize:	62.27 KB
Viewed:	235 Time(s)
This image has been reduced to fit the page. Click on it to enlarge.

---

---

3240106 Droner.jpg
Description:	PHOBoS - 3240106 Droner build
Filesize:	32.26 KB
Viewed:	83 Time(s)
This image has been reduced to fit the page. Click on it to enlarge.

---

---

PHOBoS - 3240106 Droner Demo - hands off (Jun. 11, 2011).mp3
Description:	Letting it drone on it's own	Download
Filename:	PHOBoS - 3240106 Droner Demo - hands off (Jun. 11, 2011).mp3
Filesize:	2.48 MB
Downloaded:	186 Time(s)

---

---

PHOBoS - 3240106 Droner Demo - pots (Jun. 11, 2011).mp3
Description:	Turning some knobs	Download
Filename:	PHOBoS - 3240106 Droner Demo - pots (Jun. 11, 2011).mp3
Filesize:	5.39 MB
Downloaded:	174 Time(s)

---

---

PHOBoS - 3240106 Droner Demo - delay (Jun. 11, 2011).mp3
Description:	delay added	Download
Filename:	PHOBoS - 3240106 Droner Demo - delay (Jun. 11, 2011).mp3
Filesize:	2.14 MB
Downloaded:	153 Time(s)

---

[PHOBoS]

For the second droner I experimented with a XOR ringmod, which resulted
in the following circuit: "XOR Stereo Droner"
- as with the previous circuit this one also has 2 oscillators to set a base
drone, but this time both are slowly and slighty modulated by a triangle
wave. The outputs are attached to an XOR. What I didnt know before is
that if you add an LED to the output it will fade in and out in sync with the
frequency shifting produced by the 2 oscillators. So this is also very
usefull to use in future drone circuits as an indicator.

- I used this fading effect to modulate a third oscillator which is also XOR'd (?)
with the other 2 oscillators.

- with so many outputs and a spare inverter I decided to make a stereo
version. Mixing is done in the same way as the previous circuit but I did
use different resistor values for the XOR outputs and the direct oscillator
outputs.

schematic, a photo and some demos:

---

XOR Stereo Droner.gif
Description:	PHOBoS - XOR Stereo Droner schematic
Filesize:	59.5 KB
Viewed:	181 Time(s)
This image has been reduced to fit the page. Click on it to enlarge.

---

---

XOR Stereo Droner.jpg
Description:	PHOBoS - XOR Stereo Droner build
Filesize:	34.48 KB
Viewed:	77 Time(s)
This image has been reduced to fit the page. Click on it to enlarge.

---

---

PHOBoS - XOR Stereo Droner Demo - hands off (Jun. 11, 2011).mp3
Description:	Letting it drone on it's own	Download
Filename:	PHOBoS - XOR Stereo Droner Demo - hands off (Jun. 11, 2011).mp3
Filesize:	5.02 MB
Downloaded:	164 Time(s)

---

---

PHOBoS - XOR Stereo Droner Demo - pots (Jun. 11, 2011).mp3
Description:	Turning some knobs	Download
Filename:	PHOBoS - XOR Stereo Droner Demo - pots (Jun. 11, 2011).mp3
Filesize:	3.66 MB
Downloaded:	164 Time(s)

---

---

PHOBoS - XOR Stereo Droner Demo - delay (Jun. 11, 2011).mp3
Description:	Delay added	Download
Filename:	PHOBoS - XOR Stereo Droner Demo - delay (Jun. 11, 2011).mp3
Filesize:	6.36 MB
Downloaded:	143 Time(s)

---

[PHOBoS]

If anybody has some nice drone circuits please post them.
here's some that are probably well known:
beavisaudio Heterodyne Space Explorers
Casper Electronics Drone Lab V2

[tjookum]

Awesome stuff Phobos!

Almost missed this one since I rarely venture outside the lunetta forum...

I really like your ideas and your schematics look great, definately going on my backlist. And about controlling the offset, have you seen this?
http://electro-music.com/forum/topic-48083.html
I think that is a beatifull way of making a drone with minimal controls.


I've also been heavily focussed on Drones lately and they are just endless fun. Im working on the second version of my Organ Dronor and Im really learning a lot about filters and mixing. One of my favorites is to mix the oscillators together with diodes instead of resistors, really adds more flavour.

I don't have a finished schematic but I added a little taste of the dronor. Im using some very old diodes from a power supply wich tends to sustain the drone longer but any diode will do. The little added circuitry in grey changes the output from ramp to triangle to saw. You can also add diodes across the variable resistors on the oscillators with the same effect.

here are some of my drone explorations:


and a lot of recordings, some more succesfull then others:
the Organ Dronor by Tropical Benny

---

organ dronor V2.1.png
Description:
Filesize:	15.45 KB
Viewed:	154 Time(s)
This image has been reduced to fit the page. Click on it to enlarge.

---

[v-un-v]

Thanks very much for posting these Phobos. I've been lusting after a nice drone box ever since I clapped ears on the Drone Commander. I'd love one of those, but not at that price