doepfer a-172 maximum/minimum selector price : $75.00

a-172 is a minimum/maximum selector module and is equipped with four analog inputs and two analog outputs (minimum, maximum). the main application of the module is the processing/mixing of control voltages, e.g. random voltages, adsr, lfo, s&h, ribbon cv, theremin-cv and similar, but even for audio signal processing the module can be used (e.g. several outputs of the same or different vcos).

the module permanently picks the maximum resp. minimum voltage out of the four input signals and outputs these voltages to the maximum resp. minimum jack socket.



to adjust offset and amplitude for each input independently (i.e. to bring the signal into the right "position" with the desired level) we recommend to combine the module with the a-129-3 slew limiter/attenuator/offset generator (see patch example below). the other sketch below shows the basic principle of the max/min module by means of three sine waves (e.g. three lfos) with different frequencies and different levels.

working principle of the maximum / minimum module


the upper section shows three input signals for this example: green, red and blue lines (three sine waves with different frequencies and levels). the lower section shows the corresponding outputs for this example: yellow (maximum output), magenta (minimum output)

patch example: travel filter
see diagram 1

this example emulates the "travel filter" of the korg 700. the audio signal is processed by a low pass (e.g. a-122) and a high pass (e.g. a-123). without external cv the manual filter controls are adjusted so that the two filters form a band pass with a small bandwidth. the first cv connected to the a-172 controls the filter frequency of the resulting band pass. the "travel" cv (tcv) is used to open the band pass to lower frequencies (tcv<fcv, hp frequency becomes lower) resp. to higher frequencies (tcv>fcv, lp frequency becomes higher). the frequency of the other filter remains unchanged (i.e. lp = fixed while tcv<fcv resp. hp = fixed while tcv>fcv).

patch example with a-129- slew limiter/attenuator/offset generator


this example shows how the a-129-3 can be used to adjust attenuation and offset for each of the four inputs of the maximum/minimum module. the "new" inputs are the four upper inputs of the a-129-3.



this module has a maximum current draw of 10ma. it requires 4 te/hp worth of space to fit in a eurorack frame.

to view this module's user manual as a pdf file, please click here.