The 2CVADD-HQ has 2 separate circuits which are useful for controlling CVs more accurately for pitch, to keep things in tune. This could be for any 1V/Octave synthesisers, (doesn't have to be the AE modular). This accuracy is useful for to Oscillators and Sequence modules, but could be good for many purposes.
If you would like to have transposition buttons to shift by one or two octaves (or an adjustable amount), take a look at the CVADDER-HQ module
The most obvious use is before a VCO, (e.g. 2OSC/D) to combine CVs to control pitch. Having 3 outputs each circuit could control up to 3 oscillators without any help. The inverting input (4) on circuit A can be really useful here.
The same applies for controlling filter cutoff frequency.
This module can be used as a CV mixer anyway, regardless of destination, again Input 4 on circuit A can be really handy.
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