Wiard Model 1210 "Noise Ring" Data Resonator
Faceplate of the Model 1210
3" Frac-Rac compatible module with Blacet power connector
A source of random voltages and noise-tone hybrid sounds
Introduction:
NOTE: The empty socket on the PCB is for test or expansion. It is normally empty! The pinout for the socket J10 is at the end of the manual.
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.
Knob Twiddling:
A longer sample involving just adjusting the various settings on the module by itself: Playcontrol1.mp3
Block Diagram of the Model 1210
Tone Wheels and Noise Rings:
Clocked at audio rates, the shift register forms a kind of synthetic "tone wheel", similar in idea to the electromechanical tone wheels in organs. But with very crude quantization, and hence very "noisy". To some extent you can visualize the resistor summers (DACS - digital to analog converters) like the lines of magnetic force around a metallic tone wheel. Different summers form different kinds of pickups. It is actually a digital transversal filter, but the "pickup" idea is helpful.
All voltage ranges are from 0 to 10 volts. The Aux Output (n+1) will change between one of 9 voltage levels. The Output (2^n) will change between one of 256 voltage levels.
Noise Source:
The module contains an internal analog white noise generator. Random digital data is generated by using two comparators to compare the noise voltage against two DC voltages. One comparator generates a controllable density of zeros or ones. The second comparator controls the solid state switch which which selects between recycling old data in the shift register, or getting new data from the outside. If the "CHANGE" control is set to 100%, ALL new data is shifted through the register. With the "CHANGE " control set to 0%, only old data is recycled through the shift register without change.
CLOCK:
A wide range voltage controlled oscillator is used to clock the shift register. The 4 decade range from 1 Hertz to 10 Kilohertz, allows the generation of audio rate sound and also control voltage sequences. The VCO has a coarse set front panel control and an external control voltage input with attenuator.
With the "CHANGE" control set to 100% and the "CHANCE"
control set to 50%, sweeping the clock from high to low sounds like this
at the 2^n output: Clocksweep1.mp3
With the "CHANGE" control set to 100% and the "CHANCE"
control set to 50%, sweeping the clock from high to low sounds like this
at the n+1 output: Clocksweep2.mp3
Clock controls on the Model 1210.
Clock frequency is nominally 1 Hz to 10 kHz. 0 to +10 V square wave.
Green "CLK" LED flashes when "CLOCK OUT" jack is
at +10V.
The "n+1" output is normalized to the "EXT RATE"
input. Increasing the "EXT RATE" control randomizes the clock
time.
If an external voltage source is connected to the "EXT RATE"
input jack, the "n + 1" connection is broken.
"CHANCE" Control
Controls the balance between ones and zeros in the new data. With the
"CHANGE" control is set to 100% (all new data), sweeping the
"CHANCE" control sounds like this at the 2^n output: Prob1sweep.mp3
With the "CHANGE" control is set to 100% (all new data), sweeping
the "CHANCE" control sounds like this at the n+1 output: Prob1sweep2.mp3
Chance controls on the Model 1210.
Chance controls the number of zeros and one extracted from the noise
source.
At 7 o'clock position, all zeros are output and the "Chance indicator"
LED is always off.
At 5 o'clock position, all ones are output and the "Chance indicator"
LED is always on.
At 12 o'clock position, equal numbers of zeros and ones are output and
the "Chance indicator" LED flickers.
Processing External Data
Oscillator:
Another oscillator can be used to supply data into the shift register. Connect any waveform into the "CHANCE INPUT" jack. In this case we hear the familiar "phased" sound of a swept shift register: Phaseshifter.mp3
At ultrasonic frequencies the heterodynes do a good approximation of
a shortwave radio: ShortWave.mp3
Drum Machine:
Using the Envelope Follower from an ARP 2600 controlling a Borg Filter.
The drum machine input is processed through the noise ring, then has the
envelope reapplied by the Borg Filter.
drum1.mp3
drum2.mp3
drum3.mp3
drum4.mp3
"CHANGE" Control
With the VCO set to the audible range, sweeping this control from 100%
to 0% sounds like this at the 2^n output: Prob2sweep.mp3
With the VCO set to the audible range, sweeping this control from 100%
to 0% sounds like this at the n+1 output: Prob2sweep2.mp3
Change controls on the Model 1210.
Change controls the number of new zeros and one which are let into the ring.
At 5 o'clock position, all old data is used and the "Change Indicator" LED is always off.
At 7 o'clock position, all new data is used and the "Change Indicator" LED is always on.
At 12 o'clock position, equal numbers of old and new data are used and the "Change Indicator" LED flickers.
The "n" ring lights flicker red and green as data passes through the ring.
The orange "OUT" LED will change brightness with the 2^n output voltage.
Used with a Sequencer
The following mp3s all use the same patch. The Noise Ring is used as an audible source while the parameters are varied in real time by a multi-rank sequencer. A Wiard Borg filter module is used as VCF and VCA swept by an Wiard Envelator module. This demonstrates the mixture of noise and tone that can heard coming from the hybrid oscillator.
Noise Seq 1.mp3
Noise Seq 2.mp3
Noise Seq 3.mp3
Noise Seq 4.mp3
Noise Seq 5.mp3
Noise Seq 6.mp3
Noise Seq 7.mp3
Noise Seq 8.mp3
Noise Seq 9.mp3
TECHNICAL INFORMATION
Only 1 trim point on module. Move red jumper on J12 to invert data recirculated
through shift register.
