Sound Theory -

The Concept of an Analog Shift Register

Today we will be talking about a CV Processor called an Analog Shift Register. 

The Analog Shift Register acts as a Sample and Hold (S&H) in the sense that with every incoming clock signal, it will sample the CV value of the input and make it available at the first output. 

What makes the ASR different is the fact that the CV signal will move from output 1 to output 2, and output 2 to output 3 causing the CV value to shift.

Another description is that an ASR is a multi-output sample and hold configured as a multi-tap analog memory in which control voltages are passed down a line of outputs canonically - each output receiving the voltage level previously stored at the preceding tap. 

The original model was intended for use with multiple VCOs to create an "arabesque" sound, and was created for a Serge system with different ASR type modules available in different formats. 

While there are some Eurorack Modules available that have shift register functionality, there are not many true Analog Shift Registers. 

In NAMM 2017 Intellijel released a module called Shifty that has a Shift Register Mode (SR) as well as a Voice Allocation Mode for voices (2-4) enabling one to use this module in a variety of ways including gate shifting and varying directions for use.

Enjoy exploring the depths of the shift register and other interesting modular functions that form a technique.