Tiptop Audio / Buchla 266t Source of Uncertainty

Model 266t Source of Uncertainty is a random CV generator based on the concept of controllable randomness, with six built-in functions.

The Buchla Model 266t Source of Uncertainty is a very unique random voltage generator module based on the concept of ‘controllable randomness’. It contains six different tools in one module with a classic interface. It has two types of processors and four types of generators.

Functions
Noise Source
Three types of analogue noise generator.

Pink noise (-3db/oct - emphasises low frequency range)
White noise (flat - constant across all frequency ranges)
Blue noise (+3db/oct - emphasises high frequency range)
Fluctuating Random Voltages
A CV generator that fluctuates smoothly and randomly, like a tremor or vibration.
The fluctuation speed can be set in the range of 0.05Hz (20 seconds) to 50Hz.
Each has a knob to control the fluctuation speed and a CV input.

Quantized Random Voltage
Random voltage is generated based on two predetermined equations, using the value ‘n’ that can be set with the knob and CV.
The random voltage output is updated by the gate (pulse) signal input to the Pulse Inputs.
The value of ‘n’ can be set in the range 1 to 6.
The n+1 output on the right outputs a random CV in the range 0~9V, divided into n+1 ranges.
The 2^n output on the left outputs a random voltage from the range 0~10V, equally divided into 2^n ranges.

Example of Operation

Let's say you use the 2^n output and set the knob to the value n=6.
Since 2 to the power of 6 is 64, 64 different voltages will be generated and output at random, evenly divided across the 0~10V range.

Let's say you use the n+1 output and set the knob to the value n=3.
The result of 3+1 is 4, so four different voltages (0V, 3V, 6V, 9V) will be randomly generated, evenly divided over the range 0~9V.

Stored Random Voltage
This produces two types of stepped voltage output: a random voltage output evenly distributed over the range 0~10V, and an output with a bell-shaped voltage distribution.
The centre of the distribution for the output on the right can be set using the knob or CV. Turning the knob to the right increases the distribution of higher voltages, and turning it to the left increases the distribution of lower voltages.
The random voltage output is updated by the gate (pulse) signal input to the Pulse Inputs.

Sample and Hold
The CV value input to the CV input is held at the same time as the pulse or gate rise of the Pulse Input.
The CV output continues to maintain that value until the next pulse rise.
There is an alternate output for both the CV output and the pulse output.
The CV alternate output alternately outputs the sampled and held signal. This is useful for creating a ping-pong effect, etc.
The pulse output alternately outputs the input pulse. This is useful as a flip-flop or 1/2 divider function.

Integrator
This module smoothes out changes in the input CV. The transition time can be controlled using the knob and CV.
This is useful for applications such as through limiters, portamento, and glide.

The Buchla Model 266t Source of Uncertainty has so many functions.
For this reason, it has the versatility to be used as a modulation source for various other modules, or to be self-patched within the 266t.

Width: 24HP
Depth: 25mm
Current consumption:
+12V: 150mA
-12V: 100mA