Showing posts with label DIY. Show all posts
Showing posts with label DIY. Show all posts

Sunday, 10 February 2019

NewSoundWaves Synth Meet Feb 10

Thanks to everyone who attended the New Sound Waves meeting today.


Lots of fun.


 


Thats a "wobbler" on the left and a "Rectangular Thing" in the centre.


Edgecutter & Tuesday


wE HAD THE PLEASURE of meeting Stijn Haring-Kuipers
Principal inventor, CEO of Void B.V. and Priscilla Haring-Kuipers, Resident media psychologist.of TINRS









Terry's video synth.

A 3-trins video synthesizer, Roland V4 mixer & Edirol P10 sample player.



Double Jomox Eurorack


Furrrr Generator    complex oscillator , Stillson Hammer sequencer

Love this DIY synth

Monday, 4 February 2019

Microcontrollers & Synths

This page is an index relating to microcontrollers (MCU - microcontroller unit) and how they relate to synthesizers.
It will grow over time so keep coming back

I'm seeing  these chips time and again when building synths.

They usually take the form of a single IC that contains these basic parts:
1. CPU - a microprocessor (4-bit or more)
2. non-volatile flash memory --- this holds the program to be run.
3. RAM - random access memory (volatile memory for data storage)
4. EEPROM - Electrically erasable programmable read-only memory 
    used for non volatile storage of program data
5. GPIO pins - General purpose in/out pins - used to interface with switches, LEDs etc etc.
    These can be configured to be either inputs or outputs.

Microcontrollers are basically tiny computers.
They perform things one step at a time and use a clock to trigger each step.
The clock is an oscillator (usually 1MHz to 20Mhz).

The GPIOs are very flexible ... can be ins or outs because they are controlled with software not hardware
unlike CMOS for example where the pins have a fixed function.
They are limited only by the speed and memory of the chip ( and the ability of the programmer)

Microcontrollers are also able to bridge the divide between digital and analog. So we can use them in the
world of analog synths.

There are plenty of examples of the use of microcontrollers in synthesizers.

Intel produced the 4004 in 1971 Arguably, this was the world's first microprocessor.
This led to the famous 8080 CPU and then the IBM PC's 8088, 80286, 486 etc.

The Buchla Series 300 system was introduced around 1973. It was a marriage of Series 200 modules and a computer system comprising an 8080 eight-bit CPU, a floppy disk drive, video monitor, interfaces to the synth modules, and a music language called Patch IV (developed specifically) for the system.

Buchla 360 - octal signal source

Motorola  produced the 6800 in 1974. It's a 8-bit microprocessor
    Some of the synthesizers using the 6800 & its variants were:
    The 6800 was used in the Fairlight CMI series II. The IIx used the later 6809.
    The Fairlight series III used the 6809 & 68000
    Ensoniq EPS-16 (68000),
    Oberheim Xpander, Oberheim Matrix, ( 6809)
    PPG Wave 2.x , PPG Waverterm A (6809)
    Ensoniq SDP-1  , Ensoniq ESQ1, Ensoniq SQ80 (6809)
    Quasar M8 (6800)

Fairlight IIx

 Texas Instruments produced the TMC0281 Speech Synthesizer in 1978.
 The TMC0281 was the world's first single-chip speech synthesizer.

Zilog  made the Z80 microprocessor in 1976.
This was used in many home computers of the early 1980s  like the Dick Smith System 80 which was my first computer.  

Synthesizers that used the Z80 include: Roland Jupiter 8, Sequential Circuits Prophet 5 & 10,
      Sequential Circuits Prophet 600, Roland MC4, E-mu 4060, Roland MSQ700, Oberheim OB-8,
      MemoryMoog, Emulator I and II, Akai 2700, E-mu SP-1200, E-mu Drumulator,
      Sequential Circuits Drumtraks.

Microchip Technology  introduced the PIC 16C84 Microcontroller in 1993.
      The PIC 16C84 used a new type of memory called EEPROM
      (electrically erasable programmable read-only memory).
      You will find this type of memory used in lots of drum machines from the 90's

These are some of the most common microprocessors used in modern synths. (It's by no means a full list).

Arduino

+ Snazzy Fx Ardcore
   I believe its powered by an Arduino Uno
+ Circuit Abbey Euroduino module.
 


Atmel (AVR, ARM, Arduino, ATtiny, ATmega, ATxmega, AT89, AT90, AT91)
+  Mutable Instrument
      Branches (ATMEGA88PA), Grids (ATMEGA328P), Edges (ATXMEGA32A4U)
      Shruthi - ATMega644p , CVpal
+  ADDAC -  VCC (Voltage Controlled Computer) Atmega2560
+ Elby AVR synth (AT90S8535)
+ Modular Synthesis AVR synth ATMEGA32
+ Bastl Grandpa - Atmega328-PU
+ Buchla Format - Sputnik 244 (ATtiny88 & 84)
+ Buchla Format - 204r ATtiny84A
+ Buchla Format -227r (rev2) ATTINY84A

+ Monome Teletype AVR 32 (32-bit)
ATMEGA88PA

Seeeduino.
+  meng qi voltage memory
Seeeduino V4.2

STM32 
+ Mutable Instruments
     Tides, Peaks, Streams, Yarns, Braids, Frames (STM32F103CBT6)
     Clouds, Elements STM32F405RGT6
+ Owl modular - STM32F4
+ PER|FORMER sequencer STM32F405RGT6
+ Buchla Format - 248r MaRF & 218r
+ DAFM synth - STM32
+ Axoloti -  168MHz STM32F427 microcontroller
STM32


 Teensy
 + Ornament and Crime (Teesny 3.2)
 + 16n Faderbank (Teensy 3.2)
 + Radio Music / chord organ (Teensy 3.2 with internal DAC as the audio output)
 + Temps Utile (Teesny 3.2)
 + Malekko Varigate8+ ???
 + Orgone Accumulator
 + TELEX Teletype
 + Euroshield from 1010music

Teensy is a brand of microcontroller development boards created by PJRC and designed by the co-owner, Paul Stoffregen.  Arduino +  32 bit ARM-based microcontrollers = maximum I/O capabilities

Teensy 3.2


PIC (MIcrochip)

Microchip has created its own family of MCUs and baptized them as dsPICs.
The name PIC initially referred to Peripheral Interface Controller
They are also known as digital signal PI controllers.
Early models of PIC had read-only memory (ROM) or field-programmable EPROM for program storage
All current models use flash memory  

The device families: 
+ PIC10 and PIC12 - 12 bit
+ PIC 16 - 14 bit
+ PIC 17 & 18 (21bit)
+ PIC 24
+ dsPIC - released in 2001
    (PIC24 devices are designed as general purpose microcontrollers. 
     dsPIC devices include digital signal processing - DSP - capabilities  in addition.)
 + PIC 32

Silabs (Silicon Labs)

+ Buchla 259e, 260e, and 261e use a C8051Fxxx (Model 120 ??)

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Useful Links
+ AVR synth video
+ Snazzy Effects ArdCore -Installation Demo
+ Microcontroller... What you need to program a MCU 
+ Microcontrollers... Programmers


Please let me know if there are any mistakes or omissions.

To be continued .........................

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Sunday, 3 February 2019

Statues - NLC - Build notes

These are my build notes for the Nonlinearcircuits Statues Module.
Its in eurorack format.

The name comes from the children's game Musical Statues also known as Red Light Green Light.
This is a 1 to 8 multiplexor/multiplexer….with a thru and hold circuit attached to each output.
The active output is chosen by whichever combination of the x00, 0x0 & 00x inputs is high.

The multiplexer IC can be either a DG408 or DG508 (DIP package)

You can put any signal into these, crossing 1V will send it high. In the demo video, I used the /2, /4 & /8 outputs from a Divide & Conquer which gives it a regular 1-8 count.

Using any old signals will give a more random effect but patterns will still emerge.
IN is the signal getting processed. This module can be used to process CV and/or audio signals.
-----------------------------------


A movie quote? ... Inn't he scrummy? ..

I think this is from . from Ideal ..a British dark comedy television series originally broadcast on TV channel BBC Three, ..... He is known for the line 'Inn't he scrummy?' He often talks to Moz ... He isn't particularly clever, though he is somewhat crafty.
Back to the build..........

-------------------------
S1JL Power diodes are for Reverse voltage protection -Mouser Part No: 821-S1JL. Any similar rectifier with at least 1A rating should be okay, such as 1N4001, 1N4002, 1N4004. Get these sizes; SOD-123 or sub-SMA (DO-214 is a bit too big, so avoid).




Which multiplexer to use? the DG408 or DG508?....
The DG stands for Double-Gate .... its a CMOS chip..... ie there are 2 gates in the one device.

"Multigate transistors are one of the several strategies being developed by CMOS semiconductor manufacturers to create ever-smaller microprocessors and memory cells, colloquially referred to as extending Moore's law."

The DG408 is an 8 channel single-ended analog multiplexer designed to connect one of eight inputs to a common output as determined by a 3-bit binary address.
https://au.mouser.com/ProductDetail/Renesas-Intersil/DG408DJZ?qs=sGAEpiMZZMutXGli8Ay4kA%2fBPd2gF8jLzm9LT6sd4BM%3d

The DG 508 is a Multiplexer Switch ICs 8:1 CMOS Mid Voltage MUX
 https://au.mouser.com/ProductDetail/Maxim-Integrated/DG509ADJ%2b?qs=%2fha2pyFaduielkf44kdqC6FI6vY%2fkDwFpufrTM%252bGuAk%3d


I chose this one & it works.








---------------------------------------

Specs

HP: 8

Inputs

xOO: first bit of a 0-7 number
OxO: second bit of a 0-7 number
OOX: third bit of a 0-7 number
IN: cv/audio signal

If xOO = 1, OxO = 0 and OOx = 1, you have the binary number 101. Converted in decimal : 5, so the output 6 is selected (you have 1 to 8 channels).

Outputs

The output selected by the x00, 0x0 and 00x inputs is fed the input signal (thru). When the selected output is changed the signal is held at whatever voltage it happens to be (ranges from approx -11V to 11V) (hold)



Links:
+ https://www.nonlinearcircuits.com/modules/p/statues
+ BOM

 + DIY index
+ All about CMOS

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You can find more NLC builds here.
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Saturday, 26 January 2019

CMP-DIV Video Effecter - Vidiffektor

I came across an old post on Electro-Music for a video effects box.
 http://electro-music.com/forum/viewtopic.php?t=54113

It looks very cool
Credit for this goes to James Schidowsky.
His website is here:
http://www.jamesschidlowsky.ca/electronics.html

The info in the post is very clear with lots of schematics and even a breadboard.
The parts count is very low.
Just two ICs ... a LM339 quad voltage comparator and a CMOS 4040
Should be a fun DIY build.

Links:
youtube 1
youtube 2
Workshop
Facebook workshop Aug 2018

I've ordered some parts and will document the build on this page.
To be continued................... 

Wednesday, 23 January 2019

The Integrator Circuit - analog computers, Buchla, Serge & eurorack modules

The Op-amp integrator is a very important electronic circuit which I come across again and again.
The West Coast style of synthesis uses it a lot in modules like function generators, and slope generators.
In the synth world, what is possibly the most popular of all modules, the Make Noise Maths I think uses this circuit. (let me know if I'm mistaken).



The Fritz chaos circuits are also made of integrators.

The op-amp integrator is, as the name implies, based on the operational amplifier (op-amp). It performs the mathematical operation of integration (with respect to time). The magnitude of the output voltage is proportional to amplitude as well as the length of time a voltage is present at its input.

This probably sounds like lots of gobbledy gook to most people. Sorry.
To simplify all this nerd stuff.....
Usually operational amplifiers are used as part of a feedback loop circuit involving a resistor.
 Something like this:


 But what if we swap the resistor with a capacitor?
We now have a RC network This new circuit is commonly called a Op-Amp Integrator


Electronic integrator circuits can be found  in old analogue computers:

The COMDYNA GP-6

Integrators, mutipliers, dividers, counters, function generators, operational amplifiers, differential amplifiers, voltmeters... etc etc... These old analog computers had many of the modules you will commonly find in a modular synthesizer. They are arguably the inspiration for many of today's synths.


 Digital systems Lab

Anyway, probably my favorite module, the Buchla 281 QUAD FUNCTION GENERATOR uses it, as does the Buchla 257..... this is a voltage processor. Don experimented with integrators well before the 257. He created the Buchla 155 Dual Integrator module for  the system 100. These are extremely rare and I have never even seen a vintage one.
---------------------------------
"Model 155 Dual Integrator
Produces continuous control voltage functions when used in
conjunction with sources of discrete control voltages (e.g. keyboards, sequencers).
Positive and negative  slopes  may  be  individually  and  continuously varied from
15 volts in .0025 seconds to 15volts in 10 seconds; either or both slopes may be
voltage controlled. Particularly useful for generating complex voltage controlled envelopes,
frequency glides, and repetitive control functions." 


(from a catelog for the 1992 Ars Electronica exhibit Eigenwelt der Apparatewelt.
Pioneers of Electronic Art, edited by David Dunn)



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Buchla Dual voltage processor . Buchla 257.

It's looks a bit confusing. M is a control voltage. "It provides the capability of transferring control from one applied voltage (Vb) to another (Vc). The algebraic manipulations include addition,  subtraction, scaling, inversion, multiplication". You can crossfade & use this module as a VCA.


There is also a intergrator section in the lower right corner of the Buchla 266

 In the Serge world the DUSG (Dual Universal Slope Generator)... often referred to as the "Swiss army knife" is all about the integrator. The Slope generator is an amazing module. 


These Positive & Negative Slews preceded the DUSG


Depending on how one patches it, the DUSG can be a VCLFO,  a envelope generator; a oscillator; a  slew generator; a voltage and audio mixer; an attenuator and inverter; an envelope follower; a comparator; a VC pulse delay, a audio processor,.... whew !!! ........... it's pure genius !!!!

Bananalogue put out the  VCS almost a decade ago I think. This is based on a Serge slope generator

MATHS = DUSG/Buchla 281 and Buchla 257.???

The Befaco Rampage is another variation of the DUSG.


Just released during NAMM 2019 is the Verbos Control Voltage Processor:
It's a bit of DUSG and Buchla 257. Can't wait to get one.

So to sum up....in most op amp circuits, the feedback that is used is usually a resistor. However for the integrator this is not the case - the component providing the feedback between the output and input of the op amp is a capacitor.
It works a bit like this:
When a voltage is initially applied to Vin, the capacitor has almost zero resistance.... it acts like there is a short circuit.... so no current will flow through the op-amp. A virtual earth exists at the op-amp’s inverting input.

As the capacitor starts to charge, negative feedback forces the op-amp to produce an output voltage to maintain that virtual earth at the op-amp’s inverting input. The rate at which the output voltage increases (the rate of change) is determined by the value of the resistor and the capacitor, “RC time constant“.

Once the capacitor fully charges, it acts like a open circuit.
The flow of current then stops.

If we apply a rapidly changing signal to the input then the capacitor will charge and discharge quickly. At higher frequencies, the capacitor has less time to fully charge. This type of circuit is also known as a Ramp Generator. 
A ramp generator is a way of converting a square wave to a sawtooth.... but that's another story.