Malekko - Wiard - Xmix

The  Malekko Wiard XMIX is a mixing/crossfading utility module.

I understand it's different from the 300 series Mixolator which used a  CA3280 transconductance amplifier.

 The XMIX is 8hp wide, 25mm deep, and consumes approximately 45mA power.

There are two inputs (X and Y). 

The Y input can be inverted via a switch.

Z controls the balance of X Vs. Y. 

Z has a CV input, along with an attenuator for CV amount. 

Positive and negative outputs are provided, as well as an Expand input which provides a unity input to chain the output of other modules (such as another XMIX).

Some uses for the XMIX (Manufacturer's manual):

– A 2 > 1 Mixer

– CV crossfading

– A signal inverter

– Audio rate amplitude/crossfading modulation

– With a single input, you can use the XMIX as a linear VCA

– Input different waveforms to create new wave shapes

-- waveshaping

– The X input normals into the Y input when nothing is plugged into Y. Invert the Y input with the switch, and crossfade the X signal VS the inverted version of itself

 

 

 

 

 

 

 

 

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There is a three pin connector on the back of the PCB that goes hot-ground-cold.

Connect this to an XLR or TRS and you have a low impedance balanced send.

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mAKING  a  ADSR Envelope.

You will need two Envelators. 

 

1. Set 1st to AD mode, and 2nd to AR mode.

2. send a trigger to the 1st Envelator.

3. send a gate to the second envelator .

4. take outputs of each Envelator into the inputs of the xMix

    AD Envelator plus output to X input of XMIX (X control set to max)

    AR Envelator plus output to Y input of XMIX (set Y polarity to plus and Y control to max).

5. The ADSR envelope is available at the XMIX plus output 

6.  The XMIX "Z" control acts like a "Sustain" control.  

     The "ZMOD" input can be used as voltage controlled sustain level input.   

 

Take the output of the xMix and input into a VCA 

The Wiard Xmix can be used as a mixer & as a VCA.

I find there is a little bit of audio bleed when I use the Xmix as a VCA.

I prefer to use a dedicated VCA for this task.

 

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Balanced (ring) modulation. 

• 1. Make sure the X & Y knobs are at full.
  2. Connect your carrier sine wave (or whatever) to the X input.
  3. The Y input is normalled to the X input so the carrier is going to X + Y.
  4. Switch the Y input polarity to negative (minus).
  5. Monitor the plus output.
  6. Adjust the Z control to get the best carrier null.
  7. Now run anything into the Z control input (modulator), Z Control is the volume for the modulation input.

 Thanks to "shady smiles" for the ring mod patch.

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

Unbalanced modulation (VCA)

 

 X in = Audio in

+ out = Audio out.

Zero both Y & Z pots.

Z control pot is set to Max

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

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Links:

+ Muffs

+ waveshaping (youtube)

3TrinsRGB+1c build pics & initial tests

3TrinsRGB+1c is an analog audio/video synthesizer

 This build took about 3- 4 hrs. It's not difficult but it's not for beginners either.

Some closeups from various angles. Hopefully this will help future builders.

The pot in the foreground is the only 20K one . ... has the gold top.

There is a transistor missing in the above pic -- to the left of the 10uf cap.

This is the 2016 version

..

 Note the two resistors below "VidIn"
 In the pic below, the 10R is missing.

First tests:

The middle white LED didn't work, so had to be replaced... just like in GGs video.
I don't think the LEDs effect the operation of the buttons.

Nice, the video in works perfectly.
The manual is here:
http://gieskes.nl/instruments/files/3TrinsRGB1/3TrinsRGB1c-manualV1.pdf

Watch this video at least twice before you build anything.
Essential viewing.
https://www.youtube.com/watch?v=QqKOfuUpSV8

And GGs website is here:
http://gieskes.nl/instruments/?file=3TrinsRGB1
Assembly instructions:
https://www.flickr.com/photos/62323010@N00/26454192491/

LZX basic patches

 Some very basic patching with an LZX modular. Using two waveform generators (right), a doepfer A110 VCO and a color video encoder.

Adding in a sensory translator and two logic modules: video divisions & video flip flops

The system is slowly coming together.

Links:
1. Advanced patches

While Loops - Arduino

 While loops

Allows more flexibility than a for loop.

A while loop will loop continuously, and infinitely, until the expression 

inside the parenthesis, () becomes false. 

 

Syntax

while (condition) {
  // statement(s)
}

 

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

Example Code

var = 0;
while (var < 200) {
  // do something repetitive 200 times
  var++;
}

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

 

 

//This code will print the numbers 1 to 10

//print a space

//then loop

int j; // counter
int delayTime=100;

void setup()
{
  Serial.begin(9600);
}

void loop()
{
  j=1;
  while (j<=10){
    Serial.println(j);
    delay(delayTime);
    j=j+1;
  }
  Serial.println(); // prints a gap
    
}

 

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

 example 2

while the voltage at the pot is less than 1023 (5V)

the LED is off.

Any voltage above this turns the LED on.

 

int j; // counter
int potVal; // 0 to 1023(5V).. value of pot
int delayTime=100;
int potPin=A0;
int redPin=7;


void setup()
{
  Serial.begin(9600);
  pinMode(potPin,INPUT);
  pinMode(redPin,OUTPUT);
 
}

void loop()
{
  potVal=analogRead(potPin);
  Serial.println(potVal);
  delay(delayTime);
 
  while (potVal>1000) {
    digitalWrite(redPin,HIGH);
    potVal=analogRead(potPin);
    Serial.println(potVal);
    delay(delayTime);
    
    
    
  }
 digitalWrite(redPin,LOW);
    
}

 

 Links

+ Paul McWhorter Tutorial 17

 

 ---------------------------------

+ Arduino Index 

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

Compressors for Audio

 This is an attempt to demystify audio compressors.

They are useful both in the music studio and when performing live.

It's all about reducing & smoothing the audio peaks and troughs.

I have a few different types, ranging from small modules to rack units.

They all however have similar controls.

There are also quite a few eurorack compressors.

My favourites are the WMD MSCL and the L-1micro compressor 

You can actually build a compressor with a envelope follower, a an inverter and a VCA. A modular compressor is essentially a voltage controlled envelope follower tied to a VCA.

 

+ Modular Compressor -using eurorack modules

 

 

The MSCL is unusual in that it doesn't have the usual controls.It's inspired by the classic 

DBX "over easy"style compressor . The threshold, gain & output are all controlled with one

knob and two switches. 

 

This is an excellent stereo compressor for a small modular system. It packs in a lot for just 4HP

 

The Limit Switch limits the make-up gain allowing the MSCL to act like a peak limiter. 

The Threshold Switch helps compress signals of different amplitudes. Both modular & line level.

Both switches have 3 settings:left (off), middle(half on),right (full on).

The side chain input helps create your ducking sounds.

 

To turn on the compressor, I like to turn the LIMIT to the left & 

THLD (Threshold) slide switch to the middle to start with.

 

The Limit is your final volume. 

The Threshold is the volume the audio has to reach before compression begins.

 

I usually end up with both switches in the middle or maybe one of them 

to the right (usually the threshold).

Often I'm mixing Line Level audio with Modular audio and these have 

huge volume differences.

 

The lower toggle switch needs to be in the centre position.

I usually set the COMP knob to around 75% and GAIN to 50%

As you turn up the COMP knob you will see the LED change from red to green.

Red is your gain reduction. Green is gain addition.

(The GAIN knob is your Makeup... so use it at the end of the audio chain). 

Play around with the envelope. Turning up the attack will let the

beginning of your kick drum through. These envelop knobs are a great

performance feature

The bottom 3 throw toggle switch has side chain, in, out.

IN = wet compressed signal

OUT = dry uncompressed signal.

Switching between these two is a great way to compare.

As WMD say in their video .. "don't be afraid to use your ears"

Just listen to how each sounds and make your adjustments accordingly.

Threshold

 This sets the volume the audio has to reach before compression begins.

It acts like a gate. 

Adjusting this control sets the level at which the gate will open and allow the signal 

at the input to pass through to the output.

Ratio

This is the amount the audio is reduced (over the threshold).

It's as the name suggests a ratio.

When an input signal is above the THRESHOLD reference level, the setting of this control determines the number of decibels (dB) by which the input signal must change in level to produce a 1dB increase in the signal level at the output

 

Common ratios you will see are:

1:1

1.3:1

2:1

3:1

4:1

Infinity :1

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

 

1:1 is no compression

Infinity :1 , Here the compressor acts as a limiter as audio will never exceed the threshold.

 3:1 here the audio above the threshold is compressed a third.

So if the sound peaks 15dB over the threshold, it will be attenuated to 5dB over the threshold.

 

I tend to set the ratio between 3:1 to 10:1

Above this, it tends to clip the audio.

 

Attack

The ATTACK control is an envelope. Just like a ADSR. It sets the amount of time it takes the module to begin compressing a signal once the threshold is breached. The ATTACK range is from FAST (for a tighter and more noticeable compression effect) to SLOW (for more delayed, gradual compression). 

 

Release

The RELEASE control sets how fast the compression circuit returns the input to its original level. 

Again this is very similar to the ADSR envelopes you are used to with modular synths. The RELEASE rate is from FAST (where the compression slope is steep) to SLOW (for very smooth, gradual compression). 

 

There is no absolute right way to set the ATTACK and RELEASE controls.

MakeUp / Output Gain

The OUT-PUT GAIN control  is also known as MAKE-UP.

It does not interact with the threshold of compression.

Use it to compensate or Makeup for any drops in the final volume which may have occurred during compression 

 

Knee

While discussing the MSCL compressor above, I mentioned the DBX "over easy" style.

This is where Hard vs Soft knees curves come into the discussion. 

"Over easy" seems to be dbx's way to describe a "soft knee".

A soft knee will yield a generally "softer" more subtle compression effect. 

 

It is, in effect, a variable threshold since there is no distinct point at which processing begins.

The compression ratio will start climbing gradually before you approach the threshold as opposed to suddenly "kicking in" all at once at the threshold. 

 

Some compressors have an adjustable knee. I haven't seen many of these in the eurorack format

 

Multi-Band Compression.

There aren't many of these in Eurorack.

Here, the sound from your modulars is split into multiple frequency bands using modules like

EQs. Three bands is the most common number. 

Each frequency band is then compressed separately after which the audio streams are

mixed back together.

I particularly like the Endorphin.es golden master.

It's a 3 band equaliser with a compressor for each band.

Just 6HP

What it lacks in compressor controls it makes up for in size and ease of use.

Sounds great too.

2HP also make a compressor.

It might be fun to have a few of these chained to an EQ to make a multi-band compressor  with lots of control

 

Peak vs. RMS

Peak value is the highest voltage that the waveform will ever reach, like the peak is the highest point on a mountain. The RMS (Root-Mean-Square) value is the effective value of the total waveform.

When it comes to compressors, these two settings refer to response times.

Peak compression is great for things like drums.The compressor's changes occur much quicker.

RMS changes are slower and good for slower sounds like strings or pads. 

 

 

Sidechain

This effect was first developed in radio studios. The background audio could

be dropped automatically when the announcer spoke. 

Thus, the volume level on one instrument is controlled by the volume 

level of another instrument. A common example would be making the 

compression level on a bass controlled by the output volume of the 

kick drum.  This is called Ducking.

 

I really like the endorphin.es Cockpit. 

Though it's not marketed as a compressor, it's ducking is great for getting

that pumping sound. 

It's really a mixer with a VCA.  

 

 

 

 

 

 

 

 

 

 

 

 

Feedback (feed forward) compression.

Here, the input signal is split into two. One goes into the compressor itself.

The other goes into the sidechain. The sidechain is then fed by the output of the compressor.

This type of compressor was made famous by the Universal Audio 1176.

 

LIMITING

This is where you set the max volume your signal will reach.

It provides overload protection.  

 

 

The Audio Damage ADM10 Kompressor is DSP based.

Just 6HP. Nice 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Other eurorack compressor modules

+ Autodyne - SSF

+  Dynamo - Bastl

+ Mutant Hot Glue - Hexinverter

+ Mutable Instruments Streams 

 

An example of a compressor in a pedal format.

Links

+ 172 - Dual Signal Leveler

+  Julia Bondar - Live rig

+ L-1 Compressor 

+ DBX compressor 166 manual 

+ sidechain compression - eurorack modular

Stoic Logic - basic intro

 

There are actually two systems of logic in the classical world.

Stoic and Aristotelian.

 

This page covers some basic ideas of Stoic logic. 

Stoic L is also sometimes called Propositional Logic.

 

Stoic Logic was first developed by Chrysippus, in the 3rd-century BC.

It's teachings were "lost" for many centuries and only rediscovered in the 20th century .

The first person to reappraise their ideas was the Polish logician Jan Łukasiewicz.

 

There appear to be close similarities between the methods of Stoic reasoning and the behaviour of digital computers. ... The code of the nineteeth-century logician and mathematician George Boole bear much in common with Chrysippus. Propositional logic is thus closely related to modern mathematical & Boolean logic.

 

Stoic logic is different from Aristotle's term logic because it was based on the analysis of propositions rather than terms.

 

Aristotelian logic uses terms like all Xs are Ys, some Xs are Ys, and no Xs are Ys

A example is: All men are mortal. Dion is a man.

A conclusion is reached by rules known as Syllogisms.

eg: Therefore, Dion is a mortal.. 

 

Propositional logic uses Propositions. (statements that are either true or false)

It also uses operators ( logical connectives) like the Conditional, Paraconditional, Conjunction, and Disjunction, etc

An example: 

If X then Y; 

Both X and Y; 

Either X or Y. 

These propositions and operators can be combined to create more advanced statements too, like: If A and B, and C or D, then it is not the case that E.

 

So to summarise:

Stoic Logic a system of deduction which uses 2 parts:

1. propositions (statements that are either true or false)

2. operators or logical connectives (which act upon the propositions). 

 

Stoic logic starts with simple propositions. A favorite examples from the ancient texts:

• Dion is walking.

 We can turn this into a complex proposition by using an "operator".

These are really similar to boolean operators

Boolean Operators are simple words (AND, OR, NOT or AND NOT) used as conjunctions to combine or exclude keywords in a search

 

Stoic  propositions "operators" use terms like:

 

    Conditional (if) :                                        If it is day, it is light.
    Paraconditional/Pseudoconditional (since): Since it is day, it is light.
    Conjunction (and) :                                    Both it is day and it is night.
    Disjunction (either ... or) :                          Either it is day or it is night.
    Causal (because) :                                     Because it is day, it is light.

    Comparative (more/less likely .... than  :     more likely it is day than night     

    The more: It is more day than it is night.
    The less: It is less night than it is day.
 

 

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

+ Philosophy index  

Serge DSG - Dual Universal Slope Generator as an oscillator

Sounds like a spaceship taking off.

I'm revisiting the serge after a very long break.
That DSG (DUSG) is wonderful. Here I'm using it as a VCO but it can be
so many things: clock, pulse divider, envelope follower, Filter, AR Envelope Generator, VCA, LFO, CV & slew limiting processor.

To use as a oscillator you need to patch the "gate out" into the "input" or into the "trigger in".

There are two outputs : Bipolar & classic.
I've patched one into a triple waveshaper (TWS) and the second into a wave multiplier.

It's great esp when used in series as each waveshaper adds a fold to the waveform.
See Ken Stones site:
http://www.cgs.synth.net/modules/cgs85_tws.html

The TWS will transform a sawtooth wave into a sine wave.

There are 3 sections to this wavemultiplier. Each is different.
The top section has two settings. "Lo" ... behaves like a linear VCA.
or "Hi"... clips or squares up incoming waves....good for distortion.

Middle: It gives odd harmonics which sound like wind instruments.
These odd harmonics are often described as "rough" or "dissonant".
I still like the sound ... filter like & full of resonance. The waveforms appear to be clipped using a series of diodes.

Bottom: "performs non-linear wavehaping known as full-wave rectification". (Ken Stone). It gives even harmonics.
Even harmonics generally sound more 'musical' because the original note is reproduced, although 1 or more octaves higher.

The wave multiplier is really powerful timbre modifier. ... and in such a small package.
It's ability to produce odd & even harmonics makes it very musical.
Kind of like the Buchla 296. Though this is more of a filter.

In the late 1960's Buchla made the 148 Harmonic Generator. It used waveshapers to create 9 harmonics above the fundamental. The even harmonics are created with full wave rectifiers just like in the bottom section of the Serge Wave Multiplier.
And the odd harmonics also use diodes as in the middle section of the Serge WM. 
I don't own a 148 (it's extremely rare), but the closest I have is Verbos' Harmonic Oscillator, the 262v.