Thursday, December 22, 2011

cd4046 as Pitch Tracker

I have been experimenting more with the 4046 PLL chip after finding some great projects in Nic Collins' book, "Handmade Electronic Music": http://www.nicolascollins.com/books.htm

I adjusted some of the values in the schematic to utilize the parts I had on hand. I also removed the 4049 gain circuit used in Collins' design.  It had minimal effect in my Lunetta and there's no need to use it unless you are trying to square up the incoming signal; like from an electric guitar.


SpaceNuts by Draal

Galaxian by Draal
In the tracks above, I fed it the output of my 4052 module (4 inputs where A and B select which input is 'on').  SpaceNuts uses a 22n cap while Galaxian uses a 1uF cap.  The larger cap doesn't track as acurately as the smaller one,  but does offer a great "dive bomber" effect!  Having a switch to choose between two caps like this sounds like a fun idea.

Updated version for Lunetta Use
The effect is quite nice; turning barely audible clicks into a richer pitch making endeavor.

Tuesday, December 20, 2011

A Rather Unique Mixer: a 4X4 Matrix Mixer to Be Exact!

Tired of your run of the mill mixer for your creative endeavors?  Then please have a look at my friend, concretedog's beast.   Here is a shot of the schematic from his November 2010 archives:
http://concretedog.blogspot.com/2010/11/finishing-off.html



MATRIX01 by concretedog
Head over to his excellent site for more of his experiments as well as checking out his awesome music he's making.  http://concretedog.blogspot.com

4051 CV Generator Module

The 4051 is an analog multiplexer otherwise known as a digitally controlled analog switch.  Three controllers, A, B and C decide which of the 8 channels turn 'on', making it perfect for lunetta use.  You can simply wire the ins and outs to a panel and connect them to the other  modules in your machine and be quite happy.

But I want to show you how to make something even cooler: The 4051 CV Gen.  It's a variant of the 1 Bit Custom Waveform Generator posted here.  I used individual SPST switches instead of the DIP switch idea and I brought AB and C of the 4051 out to the panel to make em' patchable of course.  Big shout out to RFeng over at the "forums" for his suggestions!
Inside 0ut by Draal


 The recording above was done live straight to my Ipad and recorded with the Soundcloud app.

Connect a few oscillators to the AB and C controllers, adjust their respective speeds, and flip a few switches until you are pleased.  Then mix it up by substituting one or more of the oscillators with the outs from some of your other modules.


Tuesday, December 13, 2011

The 4015 Shift Register Continues to Surprise

While experimenting with the fun 4018, I decided to unplug all the various gates and oscillators and start fresh. I asked myself what else haven't I tried connecting to those Jam inputs? Then it dawned on me that I could use 4 outs from one half of my 4015 shift register.



Results: Awesomeness.  Awesome in its simplicity.  I have 2 oscillators going into the clock and data pins of the 4015. I connect the 4 outs into the jam inputs of the 4018. It also has clock and data pins connected to 2 oscillators. Output this to your mixer/amp and tweak to your heart's content.

More on the cd4018

By connecting some of the outs of a 4017 counter to the jam inputs of the 4018, you can get some very interesting patterns quite easily.  My setup for this track:
  • 1 oscillator to clock the 4017
  • 2 oscillators for the Clock and Data inputs of the 4018
  • 5 outs from the 4017 (pins 3,2,4,7 and 10)
  • Pin 1of the 4017 is connected to the Reset pin of the counter
  • Pin 13 of the 4017 is tied to ground; pin12 no connection
There is the addition of the 4040 and 4052 to add some texture to this track.

This track uses a modded Danelectro Slapback Delay pedal which then goes out to my Vox Pathfinder amp, and then Line Out to my Mac running Audacity.

Here's is a stripped down example of the 4017 and 4018 without any other cmos action other than clock and data sources for the 2 ics.

Sunday, December 11, 2011

Using the 4093 as PWM Part 2

Here's an example of the PWM with an added LFO into pin 4 of the 4093.  The addition of the LFO, or any slow oscillator into the PWM creates plenty of sonic mayhem to experiment with.  The PWM circuit will work perfectly fine without the added modulation in your lunetta however, bringing an input jack from pin 4 of the 4093 to the panel is easy enough to do.



Thursday, December 8, 2011

Guitar or Mic Input: Draal's Take on the PWM

I found a great and simple circuit for making a guitar signal "square" and thought it would work in my lunetta.  It's based off of Tim Escobedo's PWM and I used parts I had on hand.  I used a 4093 instead of a 40106 and I also replaced the 500k pot with a 100k.  The .005 cap was replaced with a .0047 as well.  No need for the DPDT switching:  Just run a banana jack to pin 3 of the 386 and your out jack right after the .1uF cap on you cmos chip.



You can add the LFO that's shown in the layout if you want to take advantage of the unused pins of the 40106.  This clip doe not have an LFO modulating the effect.  I will demonstrate that addition soon!

Why all the excitement?  Well, how about using a guitar, keyboard, or circuit bent toy to add some interesting sounds to the mix?  I like using a mic to add vocals to my sessions as well as to provide pulses to "clock" other modules. The Pulse Width pot helps find that sweet spot to trigger other modules.

It works very well as a clock source for the 4040 for example and offers a simple way to create a sense of randomness in our jam sessions.  You could for instance, place a sensitive mic near the dishwasher or open the window when the garbage truck comes, smash around some pans....

From Tim Escobedo's Circuit Snippets

You get the idea.  This module has a ton of versatility in bringing other instruments into the experience as well as providing a pulses to manipulate other ics.  Try it!

Wednesday, December 7, 2011

The 4018 Divide By 'N' Counter

Here's a track featuring the 4018

 
I like this chip. The cd4018 is a Divide By 'N' counter in which you can preset how it divides: by 2, 3, 4, 5, 7, 8, 9, etc.  For even numbers, you're just connecting one of the Q outs back to the Data input.  For odd number of divisions, you're adding another cmos chip into the mix; the 4011.  The data sheet will help you figure out the right count you are after.  Study it :).


For my purposes, I tend to use the Jam inputs instead of just connecting a Q back into the Data slot.  I connect oscillators or outs from my gates to the Jam Inputs to get some nice patterns out of this chip.  Output can be any of the Q's:  each one may sound a bit different so let your ears decide.
  • 1 Clock input
  • 1 Data input
  • 1 Preset Enable Input (I tie High to use the Jams)
  • 1 Reset (Put on a switch or bring out to a jack to disrupt/change/gate the data flow)


All the above ingredients spell for fun times in our lunettas.  All those outs from our other chips are looking to party and chips like the 4018  are the "meeting grounds".


There will be Noise: Lunetta Jam 01

Here is a spur of the moment jam using a few oscillators to control other modules.  It shows how much of a racket you can get by mixing ;).

One oscillator goes to my divider (cd4040).  A number of outs from the divider go into a couple of 4011 gates.  The outs of the gates go to the ins of the 4052.  Two more oscillators go to the A and B controllers on the 4052.  Those inputs will determine which of the 4 channels on my 4052 gets heard.  That output goes to one of the mixer's 4 inputs.

I also have some outs from other ics going into my resistor ladder and that goes to a separate mixer input.  So I'm able to have two different sounding outputs that I can bring in or out of the mix.
Here's the video:

Saturday, December 3, 2011

Adding Effects to the Lunetta

One of the most satisfying feelings comes when you have a few modules under your belt and you start recording or jamming with your new 'instrument".  Even more satisfying, is when you start adding effects to the mix.  Enter effects pedals!

What works well with our machines:
  • Delay/Reverb
  • Phasors
  • Chorus
  • Tremolo

Overdrive, fuzz, and distortion pedals often have a less noticeable vibe at the output in my tests but your mileage may vary.  I have had some success using a fuzz to square up a weak signal;  a current project that involves mic input is calling me back to the bread board!

One of my favorite pedals is delay.  This type of effect really open up the possibilites in how you "play" your lunetta.  When looking for one, look for long delay times or at least one that can be modded to give longer repeats.

My second choice is my trusty MXR Phase 90.  The best way I can describe it: chewy!  Seriously, this effect adds a ton of character to these square waves.

Thirdly, a wah wah pedal is essentially a bandpass filter that's adjustable with your foot of course.  Sweeping from low to high easily allows for more expression during jam sessions.  Extra bonus points:  we don't have to dig into a lot of theory to achieve filtering effects.  ( We'll discuss some simple voltage controlled filter concepts in the near future though).

Sound samples:

With delay:
http://soundcloud.com/draal/cosmicreign

With phasor:
http://soundcloud.com/draal/stormtrooper

With wah wah pedal:
http://soundcloud.com/draal/submarinelost


Thursday, December 1, 2011

Build 4 Oscillators Out of a 4093

Besides the 40106, we can make a set of 4 oscillators using the 4093 ic.   We just tie one of the inputs on each trigger to power.  Or you can set up a chain where Oscillator A triggers Oscillator B when A's output brings one of B's inputs High.

A switch works great too;  just wire a SPST switch between power and input 1 in this example.  If you had a momentary switch, you can "play" or gate each oscillator to your liking.

A number of people have built "nand synths" around this principle.  When you're done with your lunetta, you will have 10 times the mojo ;)!



4093 Pinout

Wednesday, November 30, 2011

Using Leds

Lunettas and blinky lights go hand and hand.  How you go about using them depends on your personal tastes.  Most builders like to have them brought out to the panels to see how the ics interact with one another.  Usually they are mounted with the aid of those little plastic panel mount led holders at your local electronics store.

I went the other route. I'm a big sci- fi nut and I kept my leds within the housing.  I used a big sheet of acrylic from my hardware store for the back of my lunetta box.  I painted it with a semi-transparent Payne's Gray acrylic paint mixed with a clear gel medium.

The front has a fluorescent light panel that diffuses the leds very well.  With the light turned down, I enjoy a light show that doesn't focus on the perceived need to see what each ic is doing.  It's an individual thing, so go as nuts as you like.

The set up in my lunetta:
  • I use superbrights for my leds since I'm using them behind acrylic panels.
  • I connect 10k resistors to the outs of my ics and then connect the other end of the resistor to the anode of the led.  The cathode goes to ground.
  • Since I'm running my machine off a regulated wallwart, I can add as many leds as I want without the worries associated with battery only power. 


4015 Shift Register and 4046 VCO Track

Here's a track that shows how the 4046 vco sounds when three of the 4015's outs are connected to an R/2R ladder and then sent to the 4046's vco input.  Pin 14 of the 4046 gets one of the 4 outs from the 4015.  Pin 3 of the 4046 is connected to one of the outs of the 4040 divider. 

Recorded through the line out of my Vox Pathfinder and then to a mac running Audacity.  Only post work was a fade In/Out.




Monday, November 28, 2011

R/2R and VCO Usage in our Machines

We can make a large amount of sounds with the modules I have described so far, and love every minute of it. But there are some other modules worthy of your consideration: an R/2R ladder and a VCO or voltage controlled oscillator.

Think of the R/2R ladder as a simple digital to analog converter. You connect any number of outs from your gates, shift registers, and counters to the R/2R and that output will provide a voltage to send to your VCO. There is an order to the R/2R in which you have the Most Significant Bit all the way down to the Least Significant Bit. Playing with this order alters the output quite a bit.

Need a VCO? Take the easy way like I did and have something quite versatile: buy a couple of cd4046 ics.  The drawings below can be done on separate panels or on the same one.  You could get interesting results just taking the R/2R output straight to your mixer but running those voltages through the vco offers another variation on the sound.
Version 2.0

Notes:  Pin 3 and 14 are comparator and signal inputs.  These pins,when brought out to the panel, play a huge role in the variety of sounds this vco makes.  Pin 9 is where you will connect the output of your R/2R to.  The 10M resistor on pin 12 is what I had lying around.  You can experiment with other values if you like.  Same goes for the 22n;  experimentation is worth your time :).

Here's an audio sample

Saturday, November 26, 2011

Beat Beat featuring the cd4052

Beat Beat featuring the cd4052 ic at My Rockin' Basement


This is a track showing how the cd4052 works in a lunetta. There are two controllers, A/B, that decide which of the four inputs gets sent to the output. Inhibit and VEE pins are tied to ground.  The inputs can be outs from the 4040 (as in this sample), or any of the outs from your other ics. What is extra nice is that this chip has two sets of four inputs (x and y) and therefore two outputs. This recording only uses the x channel.

The simple lunetta I posted about earlier with the 4512 could easily be done with the 4052 as a substitute. I like to set this module up as my back beat, with low thumping beats and run that output to my 4 input mixer.  Then I add other modules to layer the final sound.

This recording is as simple as it gets again: recorded in one take using the soundcloud app on an ipad as recorder.  Output of lunetta is a vox 15watt amp.   No editing or effects are used in these demos.

Here's the Function Diagram of the 4052

Build a Mixer for Your Lunetta

Running all of the outs of our cmos to just one output is not much fun.  Let's build a mixer to give us greater options in creating wicked rhythms. I use an active mixer (op amp based) as opposed to a passive mixer (just resistors tied together).  The op amp of choice is a TL072 and the main advantage in using the op amp has to do with buffering.

Buffering in our lunettas will help bring all the various levels "up to snuff" so to speak.  Here's a drawing of the mixer in my lunetta.

There are many different designs for mixers out there as you know.  I built this one based off of a few different ideas I ran over with other builders.   This is my version of mixer number 3 on The Electric Kitchen's Mixer Page.  http://www.all-electric.com/schematic/simp_mix.htm
 I haven't run into any issues with this design and I think you'll like it too.

I've used the TL074 with similar success.


Here's the pinout of the TL072:



Friday, November 25, 2011

Tenuous Web. Lunetta track featuring the 4512 ic.

Just a quick demo of the simple lunetta I posted a few days ago.   This was recorded live, with no added effects or editing with the Souncloud App in my Ipad.  Record and upload:  it doesn't get any simpler than that!

This patch shows what you an do with 3 ics.  Once you cut your teeth on this basic setup, you can add more variety and depth by using a few more ics such as the 4011, 4001 and 4070.  These gates can alter your sounds with a little experimentation.

For instance, you could run 2 different oscillators into the 4070 XOR ic and then run that output to one of the ABC controllers of the 4512 or the clock input of the 4040.  How much of a web you construct is entirely up to you.

I promise you it gets harder and harder to stop adding modules :).



Thursday, November 24, 2011

Power Distribution for Your Lunetta

Here is a simplified diagram showing how to connect your modules to the centralized power bus.  I call it Master Control for short.  As you finish each module of cmos goodness, you run  a positeve and negative wire from the module to the Master Control.

Master Control gets it power from either a power supply that is bought or built or quite easily from a battery snap.


Starting your First Lunetta Module: Tip No. 1

Diagrams, schematics, datasheets are important tools to get you started for sure.  But nothing beats a simple photo in regards to construction methods.  If I showed you a pic of a finished module, the message may get lost in a sea of wire.  So for simplicity's sake, let's have a look at this photo.

I first figure out how many ics I can comfortably place on the size of perf I have.  Then I use sockets in place of the actual cmos chips.  Why, you ask?  This prevents the chips from being fried due to excessive soldering, for one.  Secondly, if something goes wrong with an ic, you can just pop in a new one.

First, I connect a 0.1uF cap as close to the power pin as possible and ground.  That's going to ensure that all our chips have a reserve of power.

Next, I use my datasheets to figure where my power and ground pins are.  I use jumpers to tie the power pins to the power bus of the perf board and all the ground connections are wired to the ground bus.

Note: While many of the ics will share similar pinouts, there can be exceptions.  Some ics use 14 pins and some use 16 so I use 16 pin sockets to take care of both sizes.

The next steps are to place pulldown resistors (100k) on the inputs of each ic.  I use a simple drawing next to me to make sure I know what each ic is which when I'm working on my board.  One leg of the resistor goes to the pin and the other leg goes to ground.

After the resistors are in place, I use green wire for the inputs and black for the outs and connect them to their respective spots.

Before I wire up the wires to the jacks, which are already mounted on the panel, I run a long black and red pair of wires that are attached to the positive and negative rails of my perfboard.  These long wires are connected to the Main Power Board, which is a board that supplies power to all the modules.





Wednesday, November 23, 2011

Simple Beginner's Lunetta or Stand Alone Gizmo

I drew up a basic diagram for a great sounding, simple lunetta that can grow as much as the builder wants.  This setup stands very well ot its own as a noise machine as well.  I am building one without the patch points exactly as I have drawn.  I wanted a small machine that I could take with me anywhere, show people the essence of what I make, etc.

Build it - It will make you happy!

This makes an awesome sounding foundation to understand the basics of lunetta building and help motivate you to even more experimenting.


The 40106 is used to build 4 oscillators: 1 for clocking the 4040 Divider (pin 10) and 3 for the AB&C control inputs of the 4512.  Tie pin 11 of the 4040 to ground.  Connect 8 outputs of the 4040 to the 8 channel inputs of the 4512.  Tie pins 10 and 15 of the 4512 to ground as well.  Output from pin 14 can be used to clock other ics, but I tend to enjoy it straight up - out to my amp.  Enjoy!

Constructing our Modules

A module can be made of just one ic on a small piece of strip board or a few.  We want all the INs and OUTs brought out to the panel, maybe add some leds and connect the module to our power source.  Choose a material for the panel:  metal, thick plastic, cardboard, etc.  There's an option for any budget.

Not into starting from scratch?  Some creative folks have recycled containers to house their lunettas.  Make a suitcase lunetta or a cookie tin machine.  

Decide on the type of interconnection you want with your lunetta first.  You can use banana jacks and cords like I have in mine or use nuts and bolts.
Lunetta and a mass of cables:  like PB&J!




 My first lunetta (above), was built with a simple wooden frame, sheets of styrene, nuts and bolts and of course alligator clips.  Cheap to build with easy to find materials. 

Here's a banana jack in comparison. You drill your panel holes, secure the banana jack with a nut, then solder your input or output wires from your perf board.
I like to look online for bulk buys with these guys.


Tuesday, November 22, 2011

Truth Tables Help Us Understand Cmos Functions

 Sometimes the information on datasheets can be overwhelming to even those of us that have worked with them for a while.  For our needs, the Truth Table will often "decode" the jargon.  Let's take a look at the 4512's truth table found on the first page in this instance.


By studying the table above, we see that depending on which combination of AB&C are High (1) or Low (0), one of the eight channels will be "heard"; that is, present its voltage to pin 14.  If Inhibit is High, we disrupt this process, bringing the output Low.  Unless I want to run the Inhibit out to a jack to gate the output, I tend to tie it to ground.  The 3 State Disable is also brought to ground in my usage to make the chip play its tune.

Here's a truth table for a bigger cmos ic, the 4043 shift register.

Here's an example:  This ic can be configured in many ways but I want it to recirculate the data I put in.  Five steps down I see my answer!  There are 4 controllers that will dictate what state the chip is in (A Enable, P/S, A/B, A/S).  For recirculation that is in sync with the clock, I tie A Enable Low, P/S High, A/B High and A/S Low.  This is a fairly complicated chip but it shows you can use it in a lunetta with a little truth finding ;).










U3F75KGRCAGK

CD4512: A Simple 8 Channel Selector

It's hard to pick the best ic in your growing collection of cmos. but the 4512 is one of my favorites.  One of the goals in patching the lunetta is to make interesting beats or sequences that have the ability to morph.  The 4512 does this without needing a ton of switches and diodes to make it work.


The pin layout is very straightforward and easy to implement.  Pins 1 through 7 as well as pin 9 are the channel inputs.  Pins 11,12 and 13 are the controllers that select which of the 8 channels is heard or "on".  Pin 15 when High, disables the ABC controllers.  Pin 10 is Inhibit.  Output is pin 14.

How to interpret this?
  • For the 8 channel inputs: connect any oscillator, gate outputs or divisions from the 4040 to them.  I like to use divisions because they have a decent pitch/octave range.
  • For the ABC controllers, connect 3 oscillators
  • Tie pin 15 to ground.  We want the 3 state selection to work!
  • Inhibit can also go to ground or can be brought out to a jack so you can decide when you wish to inhibit the effect
  • Your output can be used to clock another ic or can be sent to your mixer/amp. 
A simple lunetta using 4 oscillators (40106), the 4040 for divisions and the 4512 to select from those divisions, can make a great first machine.  The ABC controllers play a huge role in the variety of sounds that are available.

 

How to Power Your Lunetta

There are many pages describing power supplies but what works best for our needs?  Cmos are very frugal in their power consumption typically.  This makes battery power a simple and effective way to juice your machine, especially if you are designing with portability in mind.  You can even have a few leds on the outputs to go blinky blinky as long as you don't get crazy.

If you do go nuts with the leds, or simply despise batteries, you can buy a simple single supply in kit  or completed styles from your favorite electronics store or build one from scratch if you have the skills.

When building your own power supply, decide on what voltage you want your lunetta running at.  Cmos can run a 5v and up to 18v, but I never like to push things too far so I like 12v.  I happened to have a spare wallwart that was 15v and with the 7812 regulator, I can have a regulated 12v of power.  My lunetta has a few vcf's (voltage controlled filter) and i find they run great at 12v but crappy at 5v.

I built this one from PAIA: http://www.paia.com/proddetail.asp?prod=K60&cat=50

Mandatory Warning:  Whenever you deal with electricity and bare hands, there's the opportunity for accidents.  To cover my own arse, I have to state clearly: I am not responsible for any shocks or blown equipment that you may encounter if you wire up stuff wrong.  If this is your very first project, I recommend you buy a premade unit or go the battery route.

OK, that's as scary and Darth Vader -like as I get.

Sunday, November 20, 2011

The 4015 Shift Register

Shift registers like the 4015 are perfect for our builds because they have a Clock input, a Data input, a Reset pin and 4 outs.  Data enters Q1 and gets shift over during the Clock cycle.  This is a dual ic, so you can have 2 independent clocks and data inputs.

What this means kiddies:  the more we move bits around and different intervals, the better the bit crushing!  Here's the Intersil datasheet (the relevant bits anyway):

Connect an oscillator to the Clock input.  Connect another one to the Data input (or use one of the outs from a gate).  Then run the 4015's outs to other logic inputs or connect them to an R/2R Ladder which then connects to a vco.  I will talk about that set up soon!

General Practices in Building Your Lunetta

General practices with the ics you use:
  • connect a small cap (0.1uF ceramic) between the power pin and ground on each cmos chip (think of it as a little energy bottle for the ic)
  • place 100k resistors between input and ground
  • super important:  Tie all unused inputs to ground  (in some cases, an unused input needs to connect to the power supply to have a function work on the ic)
  • LEDs:  If you're using leds, just attach them to the outs of your ics and connect them to a resistor to ground (I use Superbrights and use 10k resistors on mine)
  • work with small perf boards/strip boards instead of 1 large one (easy to debug)
  • try to use color coded wire to aid in building each module (red for power, black for OUT, green for IN for example)
We place a resistor on all inputs and have them reference to ground because we want stability.  Cmos chips are sensitive little buggers when their inputs are left floating. Our lunettas are patching machines at heart, so when an ic's input isn't being connected to anything, we want to bring that input LOW through the resistor that's referencing ground.  I mention 100k resistors because I am a creature of habit, but I've had great results even using resistors as low as 22k.

The little cap between the power pin and ground helps ensure each ic in your lunetta gets enough "juice" to work its magic.  I generally add a larger cap as well between the power rail and ground when I occasionally use larger perf boards.

A 0.1uF cap between the power pin and Ground ensures that chip has spare power.

In the photo above, I did not use both halves of the 4015 to aid in clarity.  The data sheet will show you which pins are for power, ground, outs, etc.  In this case, power needs to connect to pin 16 and pin 8 goes to ground.











Thursday, November 17, 2011

Channel Selectors, Counters, Shift Registers For Lunetta Mashing

Got oscillators - check. Got dividers - check. Got Logic - check. The real fun part in building lunettas (or any sound making device), is personalizing it with ics that are seldom used by the masses.  Forget the 4017 Baby 10 sequencers or the box full of oscillators droning on and on. What will be YOUR unique machine?

There are many different types of counters, electronic switches and data selectors that really mash up these signals in interesting ways.  Head over to Jameco.com  or Mouser.com and search their CMOS pages.  As long as the ics have IN/OUT's, Clock and Data connections, you can make them work in your lunetta.

Some of my current favorite mash up ic's:

Cd4512 8 Channel Selector

Cd4052 switch (Think of it as a dual 4 channel selector)

Cd4018 Presettable N Counter

ANY type of Shift Register cd4015, cd4094 for example (I'll talk about them very soon)

Some of these chips may sound mysterious: adders, latches, flip flops, multiplexers, etc.  Don't hesitate to buy some because you don't have a clue about them.  In lunetta building, we are using (or abusing) these chips in ways that the developers didn't necessarily envision.


How to Use Cmos Logic In Lunetta Design

Okay, once you build some oscillators you are going to want methods of controlling or dictating when things go bleep and bloop. Enter CMOS logic. NOR/NAND/OR/AND/XOR may sound intimidating at first but are pretty similar in this regard. These are various Gating ics.  The High and Low state of a chip's outputs are at the mercy of the logic built in each type chip. Think of it as a set of conditions have to be met before a beep can well, beep.

Take the cd4070. It's a quad 2 input XOR chip. According to the data sheet, when both inputs are Low or High, the output is Low. When either input is High, the output will be high. By choosing your logic with the emphasis on variety, more interesting patterns emerge. Pick a few NAND and XOR gates (think of a gate as an open/closed, on/off ic) and you're ramping up the complexity in sound design without being overly complex to build. You don't need a ton of these in your lunetta to make cool sounds so add as much as your time permits.

One of the super cool things about some of these logic chips is the number of inputs. The 4012 for instance, is a Dual 4 input NAND gate, while the 4011 is a Quad 2 input NAND gate.  The 4000 is a Dual 3 input NOR gate plus inverter!  So, by mixing up the number of IN's as well as the type (NOR/NAND/XOR), the path to your sonic visions becomes a personal one.  Some sounds will be fairly gap free while at other times, there will be interesting pauses and patterns the longer it plays.

For me, it's about getting as close to the V'GER concept from Star Trek the Motion Picture as possible. 


How to Build an Oscillator




Without further delay, let's make what I like to call Master Control: our clock sources. I like to use the 40106 because you get 6 oscillators from one ic. You could also use a 4093 to make 4 oscillators; we'll look at that another time.
Essentially, we are creating an oscillator by connecting the output of each schmitt trigger (there are 6 on the 40106), back to the input. This creates a beautiful feedback loop. Add a pot and a cap and you have yourself a clock source that can be in the audible range to low frequency/LFO range.

  • Connect a capacitor between pin 1 and ground
  • Connect lug 1 to lug 2 of your potentiometer (use a bit of wire)
  • Run a length of wire to lug 3 and connect it to pin 1 of the 40106
  • Run another wire to lug 2 of the pot and connect it to pin 2 of the 40106
  • Pin 2 is your output, so add another wire here.  
Connect this output to a mixer or portable amp and you can twiddle away!  Use the data sheet to make sure you're wiring up everything correctly and build 6 oscillators if you like.  In lunetta building, you can never have too many :).  I have 8.

I recommend experimenting with the capacitor, which along with the pot, determines the frequency of the oscillator. Generally, I like to use 0.22uF, 0.47uF, 0.1uF for the audible ranges and 1uF to 10uF for the LFO. 


Why Cmos Datasheets Are Essential in Building Lunettas


In planning a lunetta or any noise box, cmos datasheets are essential. This is where you'll decide which ics to experiment with and what each pin does. We need to know where the power and ground connections are for starters. Then we need to know where the INS and OUTS are.

You'll find all types of logic in the 4000 series cmos collection. From counters and dividers to electronic switches, you'll be in heaven.

In this example, we are looking at the 40106. The datasheet describes what it does and what each pin is. We can see that pin 14 is the power connection and pin 7 goes to ground.

This chip is at the heart of many lunettas because it can give you 6 oscillators to act as sound sources or better yet, as CLOCKS for other ics.

Bottom line is: search the internet and start saving datasheets - you're a mad inventor and you're on your way!

Wednesday, November 16, 2011

My Lunetta

This is a video of my lunetta playing a tune I patched. That is the key to the lunetta experience: you connect various 4000 series cmos ics to each other via patch cables/banana jacks, screws and alligator clips - whatever your fancy.

Connect an oscillator to the CLOCK input on the 4040 for instance, and you will get divisions of that on/off state to use to connect to the ins of other ics. Take the OUTS of those ics and repeat till you are happy.

Ultimately, you'll then connect all these outs to a mixer you make (you can use a simple resistor mix for starters), then to an amp. I'll post some pics with a breakdown of what I'm referring to but for now, let the show begin.

Monday, November 14, 2011

Lunetta Sound Samples AKA We Have Wormsign

Once you start building strange sounding machines, you'll want to show off their capabilities. Soundcloud.com is my favorite host for sharing my "music" with the outside world. It's a great way to get feedback too.

Here's my Lunetta Tracks

Exit Fuzz Pedal, Enter Lunetta


I have been tinkering with electronics as a hobby for a few years now and it has been fun seeing and hearing the results of my experiments. I started with building my favorite Fuzz pedals because I wasn't about to spend hundreds of bucks on essentially a few capacitors, resistors and transistors.

Eventually I built an Atari Punk Console and while fun, I wanted more, WAY MORE!   As I pondered what to do next, my thermostat blew up during the summer. After I had it replaced, the Jabba of a tech tossed the old thermostat at me to discard.

Curiosity got the better of me and I studied the 20 year old relic. Inside the thermostat was a pcb with chips I learned were Cmos ics. They basically create the "if this happens, then this turns on/off" functions. "Hmmm, I wonder if I can rig these ics up to do weird things; make strange sounds, blow up, etc.", I said to myself.

I found the data sheets for each ic online and found out that many of them have been used to create fantastic, synthy bleeping machines: AKA lunettas.  I also found the Lunetta Forum over at electro-music.com and I was hooked!


By the way, the lunetta was named after Stanley Lunetta, who is considered the main man in turning ics like this into synth beasts. He couldn't afford a "real" synth so he found creative ways of using surplus logic ics to make his dream machine.