Monday, July 13, 2015

Doepfer A-163 Voltage Controlled Frequency Divider Tutorial Videos by Raul Pena

Raul Pena's next set of Doepfer tutorial videos is all about the A-163 Frequency Divider.

" The frequency of the input signal (preferably the rectangle output of a VCO) is divided by an integer factor N (N = 1, 2, 3, 4 ... up to 32). N can be adjusted manually and modulated with an external control voltage (e.g. from LFO, ADSR, Random, MIDI-to-CV, Theremin, Light-to-CV, analog sequencer) with attenuator.
The control input has polarizing function, i.e. the manually adjusted dividing factor can be modulated upwards or downwards. The basic idea of a polarizer is described in the modules A-133 Voltage Controlled Polarizer and A-138c Polarizing Mixer.

A-163 Frequency
The output waveform is rectangle with 50% duty cycle. Unlike the A-115 with fixed dividing factors

Applications: dynamic voltage controlled frequency division of audio signals or modulation signals. More details concerning frequency division of audio signals can be found in the Trautonium or A-113 information.

Inputs: CV In, Audio In (rectangle)
Output: Audio Out (resp. rectangle modulation CV out after modification)
Controls: Manual N, CV attenuator

After a small modification (a capacitor has to be shortened or replaced by a wire for DC coupling) the A-163 can be used for low-frequency control signals too.

Remark: From 2007 the module is equipped with an additional jumper at the bottom side of the pc board. This jumper is used to select DC coupled (jumper installed) or AC coupled mode (jumper removed).
If the module is used to divide slowly changing signals (like clock, trigger, gate or rectangle signals of an LFO) the DC coupled mode has to be selected. For audio signals the AC mode is recommended."
(2, 4, 8, 16) the dividing factor of the A-163 is voltage controlled and can be any integer value between 1 and about 20 (but only one output). In contrast to A-113 the dividing factor of the A-163 is voltage controlled and the output waveform is rectangle (the A-113 has 4 sawtooth outputs with 4 adjustable but not voltage controlled dividers).

Video: Doepfer A-163 Voltage Controlled Frequency Divider (Full Playlist)

" A short overview of the basic features of the A-163 VC Frequency Divider. A short audio demonstration is provided.
Sound and Video by Raul Pena."