Composer, electronic musician, improviser

Analog Ring Modulation Circuit

Above is a video and below are some pictures of a simple ring mod circuit I whipped up last night. The circuit is the classic circuit, and I’m simply running two oscillators from a hex schmidt 6-oscillator IC through the circuit as the carrier and modulator. The frequencies of the hex schmidt are being controlled by a PSR (photosensitive resistor) and an FSR (force sensing resistor) respectively. The video shows fairly well how the PSR reacts to the light. The function of the FSR is a little less clear visually, but you can hear it pretty plainly. I can throw up (!) a schematic of the circuit if anyone is interested, but you should be able to find one by doing a google search.

The project requires a 5V power source (batteries only!) a bread board or project board, some wire (i prefer solid-core) two diodes, two capacitors (0.1uf), 1 133k (or thereabouts) resistor, one PSR, one FSR, one hex schmitt oscillator (mm74c14n) and an audio cable or female 1/8 audio jack to run into a) an amplifier, b) a mixer, or c) your computer.  In this case I have two alligator clips attached to the cut-off and split end of a 1/8 audio cable, the other end of which is running into a mixer and then out to small speakers.

Next on the agenda I think I’m going to build me an ADSR for it. This site has a really great page on ADSRs with diagrams, circuit board patterns, etc.

Filed under: Current Projects, Miscellany, Phase 1, , , , , , , , , ,

El MuCo: PC PicturePhone Janked (plus a little Kidtunes)

On the 27th of June, in the year of our Lord (his Noodliness the Flying Spaghetti Monster) 2009, a PC Picture Phone was janked into greatness. Additional functionality was also added to the KidTunes Keyboard with some soldering and the assistance of “The MegaPot.”

The creation of the PC Picture Phone JankoCircuit ™ on the otherwise uninteresting device yielded splendid sonic results. On this page are pictures of both the Kidtunes setup, and two setups of the PC Picture Phone. Additionally, audio will be added as it becomes available (it’s being pressed onto vinyl as we speak.)

The below picture shows the new “hands-on” wiring of the Kidtunes with the megapot and the necessary switch settings.


Here is a close-up of the switch settings: from top to bottom, the settings are On/Off; Demo; Organ/Piano; High/Low volume.


A close-up of correct hand technique.  Note the left hand holding down a key…


By using the technique pictured above, the kidtunes produces a strange pitch-sweeping effect. Is some capacitor being charged and drained in this short circuit? Who the *?&# knows!

Sweeping Up and Down

And finally, the good stuff!  The PC Picture Phone was harder to get any really interesting sounds out of.  Many connections had to be made before the standard “Call the Doctor” siren call was rendered listenable.

Below is the circuit board for the PC Picture Phone as mod as we could make it after a meal of red meat, two games of Bocce, and 4 boxes of sparklers (and 11 beers).


1: the timing resistor (connected to node 4).

2: many points on the board cause the timing circuit to slow down, here there is a single node 2 shown next to 1, and the blue polygon also marked two shows an area of the board in which all nodes produce this same effect.

3: the JankoNode.  Integral to the JankoCircuit, it is this connection (or another connection on the same path not visible in this picture) that causes the Jank Effect.

4: this is the other end of the timing resistor (node 1), which causes the circuit to either speed up or slow down. The MegaPot is connected between nodes 1 and 4. 

5: i’m going to call this the LFO node as its effect is similar to modulating the circuit with a frequency of 15 Hz or so.  (with the correct resistance)

6: I can’t remember what these do… more Janking I suspect… (Kane: I remember! If you run some alligator clips between nodes 3 and 6, you get the Jank-O-Rama Effect! That’s what is pictured below–check out the audio!)


Jank-O-Rama Warning: Repeated listening may cause psychosis.

Below shows the circuit board of the PCPP with resistors removed and wires soldered into the board for ease of clipping.  Notice the black wire at the lower left hand side of the board.  This is the other JankoNode mentioned in the description of the circuit board above.


Here is a view of the whole mess.


Top view of whole mess.


The pot on the right is connected via the bread board to the timing node on the circuit board.  The pot on the left is controlling the amount of “Jank” from the JankoCircuit. We even captured low, clicky sounds by working these two pots in conjunction–very Kontakte!


Assorted clicks and clacks

The below resistor is the correct resistance for the PWM node (red6) as shown below.


The circuit with Jank pot control.


A close-up of the breadboard connections.  The PWM node is not plugged into this circuit.


Below are some voice notes taken after the session.  Please note they are tedious and mumbly (too… tired.. uh… to … uh… think…) and contain no cool noise.  They’re here more for us than for you ;)

Clip 1

Clip 2

Clip 3

Filed under: El MuCo, , , , , , , , , , ,

G O I N G S O N : L O C A L (ISH)

fritz Art of Fritz Horstman
kane Music of Brian Kane
fritz Hartford Phase Shift
fritz Hartford Sound Alliance
Lique Art of Philip Lique
Lique Music of Matt Sargeant
strycharz Art of Heather Strycharz
uncertainty Uncertainty Music Series

My Other Awesome Sites [•_•]

Assault! 375 Aural Assaults!
About me! About me!
MySpace! MySpace!
Google+! Google+!
My (soon-to-be) Company! My (soon-to-be) Company!

Enter your email address to subscribe to this awesome blog and receive notifications of new posts by email!

Join 81 other followers


P O S T E R S !







INI new haven

Handmade instruments by Scott Petersen and Brian Kane at Artspace New Haven