MamonuLabs
mamonulabs
  • Mamonulabs
    • Digital >
      • Elektron Octatrack
      • Yamaha FS1R
      • Roland S760
    • Analog >
      • Roland MKS7
      • Roland MKS30
      • Oberheim Xpander
      • Acidlab Miami
      • Roland System 100 - 102
    • myModular >
      • Rotating Clock Divider
      • Rotating Clock Divider DIY Breakout
      • Wiard NoiseRing
      • Intellijel UScale
      • Intellijel Spock
      • Intellijel UStep
      • Metalbox 8008
    • Sampler
    • VA
  • Synth Parts Info
    • Keyboards / Contacts etc
    • Electrolytic Capacitors
    • Vintage Roland Filter Info
    • Recording Equipment
  • Gear related
    • Gear lists
    • SynthGallery
    • RSS Feeds
    • Current Favorites
  • Modular
    • Articles >
      • Filters by clone type
      • The Humble VCA
      • Envelopes : Modularity v1.00
      • Virtual & Real Modular
      • East Coast vs West Coast
      • Formant Frequencies Table
      • PLL Lecture
    • DIY Articles >
      • SDIY parts sourcing
      • Decoupling 101
      • Modular & DIY links
      • Switches
      • Trimmers in CGS
      • Priciples of Electricity
    • System 100m >
      • 110 VCO-VCF-VCA
      • 112 DUAL VCO
      • 121 DUAL VCF
      • 130 DUAL VCA
      • 140 DUAL EG & LFO
      • 150 RING/NOISE/S&H/LFO
    • DIY >
      • Modular SDIY Adventures Blog
      • CGS36 Pulse Divider
      • CGS62 Slope Detector
      • CGS77 Serge VCF
      • Other DIY Projects >
        • MS-10 VCO
        • IFritz 5-pulser
        • Plague Bearer Barebones Kit
        • AM4075 Arp2600 Filter
        • Buchlaish 194 fixed BP filter
        • Fonitronik PS3100 Resonators
        • EMS Trapezoid VCA (JHaible)
        • AndrewF Double Chaos
      • Finished/Done >
        • Blacet Scanner MD2600 kit
        • Blacet Seq. Switch MD2650 kit
        • CGS35 Steiner VCF (done)
    • ToGet
    • On The Way
  • currency converter

Malekko / Wiard  NoiseRing

Picture
In latter model synthesizers, digital noise sources began to appear in place of analog ones. Traditionally, a psuedo-random shift register set up for optimal length. By optimal length, it is meant that every state of all available bits will appear at some time, but the order is unknown. Essentially a counter that counts in an unknown order. This represents the maximum state of information "entropy" available for that number of bits.

But music has close self-similarity over short periods of time. That is, it repeats itself with changes appearing slowly. This shift register generator is designed to give control of the rate of appearance of new information. It has a tight set of controls over how random it actually is and how fast change occurs.




Picture

Noisering Analysis by Babaluma

_

Comparator

“In electronics, a comparator is a device which compares two voltages or currents and switches its output to indicate which is larger.”

The Noisering has two comparators: one to determine the Chance value and to determine the Change value. The output of a comparator is 0 or 1.

Shift register

“In digital circuits, a shift register is a cascade of flip flops, sharing the same clock, which has the output of any one but the last flip-flop connected to the "data" input of the next one in the chain, resulting in a circuit that shifts by one position the one-dimensional "bit array" stored in it, shifting in the data present at its input and shifting out the last bit in the array, when enabled to do so by a transition of the clock input.”

The Noisering has one 8-bit shift register. The state of the register is translated by two DACs into a voltage in the range of 0-10 volts. One DAC (output 1) provides 256 voltage values, the other (output 2) provides 9 voltage values. ‘00000000’ is the shift register state that represents 0V, ‘11111111’ is the shift register state that represents 10V.

The shift register ‘shifts bits’ at a rate determined by the Rate pot or at a rate determined by the clock input.

Chance

The Chance pot by default attenuates an internal DC voltage. You can also supply a voltage via the Chance input. In either case the Chance voltage is compared against the voltage of an internal analog noise source. If the Chance voltage is greater than the analog noise voltage, the Chance comparator output is 1. If the Chance voltage is smaller than the analog noise voltage, the Chance comparator output is 0.

This means the more clockwise you turn the Chance pot, the greater the Chance voltage, the greater the chance the output of the Chance comparator is 1. The output of the Chance comparator is used as a ‘new value’ for the shift register input.

Change

The Change comparator works exactly the same way: an internal DC voltage or a voltage supplied via the Change input is attenuated by the Change pot and this voltage gets compared to the analog noise voltage. The output of the Change comparator determines if the shift register input gets a ‘new value’ (Change comparator output is 1), or an ‘old value’ (Change comparator output is 0).

A ‘new value’ is the output of the Chance comparator. An ‘old value’ is the last bit from the shift register. This bit gets recycled so to speak.

In practice this means that when the Change pot is turned fully counter clockwise, the input of the shift register only gets values from the last bit. This results in a repeating pattern in the shift register. If you monitor one of the DAC outputs at audio rate you will here a steady tuned tone.

The more clockwise you turn the Change pot, the more new values will arrive at shift register input, which leads to ever more changing patterns in the shift register.

Another worthy thing to note: the more the shift register is occupied by zeros, the greater the chance the DACs output a low voltage (‘00000000’ represents 0V). And of course the more the shift register is occupied by ones, the greater the chance the DACs output a high voltage.
Powered by Create your own unique website with customizable templates.