PLAN B analog blog

As the Model 23 Analog Shift Register nears design completion, I've
posted some sound samples to give you an idea why it's got us sort of
excited. Before I do, let me go into a few details on the things about
ASR's which I've personally found aggravating:

A) Outputs do not track the input voltage, making driving them with a
keyboard problematic.

B) Output taps not tracking one another so that a voltages vary as
they are passed down the line of outputs.

C) Incoming clock causing a droop in held voltages at it's falling edge.

I'm glad to say that the Model 23 does none of these things.  As the
following sound samples indicate, four separate VCOs driven by the
(now) four outputs of the ASR track to the quantized input of an
envelope generator:

http://www.ear-group.net/asr1.mp3

Same patch, but slower, giving you a clear indication of the
uniformity of the voltages as they go down the line of outputs:

http://www.ear-group.net/asr2.mp3

Same patch, at even a slower pace:

http://www.ear-group.net/asr3.mp3

Having a little melodic fun, now with the four VCOs gated through a
Model 13:

http://www.ear-group.net/asr4.mp3

Screwing around with the update speed, this time with the M23 sampling
quantized random voltages via the Model 24 give the 'classic ASR' effect:

http://www.ear-group.net/asr5.mp3

Design Changes/Improvements:

The M23 now has four independent outputs taps Clock distribution to the four S+H's is now performed by an Atmel 2051 microcontroller.  The analog memory (the capacitors) are monolithic laser-trimmed semiconductor junction type.  The added expense yields the resolution you're hearing while cutting down on the overall part
count.

For more information of the M23, go here:

http://www.ear-group.net/model_23.html

We will be seeing these along with the other first wave of ELF devices
coming in the late Spring/Early Summer.

- P