Controlling filter cutoff on LPF/HPF units

so, probably user error, but I’m failing to modulate a filter unit’s (ladder HPF as well as LPF) cutoff thru the whole range with a 0-5v cv. not if I also incorporate the v/oct control, but I’d want unquantised control, reversed so that 0v is open, 5v is closed. setting the gain of the cv to -5000 only modulates thru 1-2kHz of cutoff I think… coming to think of it after a night of sleep, -2,5v offset, 2x gain in the cv chain would prob expand the range of the modulation, but fully open to fully closed?

trying to achieve a dj-style master filter effect for the whole audio path…

The V/oct control is not quantized. :wink: Go ahead and use it!

ah! of course it is not quantised! really cannot say why i thought it would be. the mental hurdles that arise when surroundings change… thanks Brian!

BUT: i was not able to invert the modulation of the v/oct. we may have another case of a mental hurdle here, and i’ll dig deeper into that today evening…

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Turn the gain on the v/oct control to a negative setting :slight_smile:

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yeah, exactly. however, where the gain is located on the other modulators there is no gain-parameter? i thought it’s strictly a traditional v/oct input for easy accommodation of that function. yeah, gotta get home and see about it…

I see, in that case a VCA set to -1 will perfectly invert your incoming signal at any point in your chain :slight_smile:


yeah, that is absolutely correct. and obvious. mental obstacles. it must be the total openness of the architecture that just escapes me. for years I’ve approached the modular thinking ‘I can see all that is possible’. the 301 is kinda the opposite of that :stuck_out_tongue:

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It is amazing isn’t it :slight_smile:

I do believe that all the skills and knowledge that are naturally acquired through exploring the ER-301 are perfectly translatable into more general ‘modular thinking’ - it’s certainly broadened my scope, no doubt!

as some experience with a modular is (was at least for me, i think) pretty essential to even get started with the 301.

well, as to translatability; it did take me a couple of weeks to get into the workflow of it all with the 301 again after a hiatus of some months, and one quickly acquires this capacity to form a mental map of the patch in the 301. and then the capacity to innovate within that map, expanding on it, working with VCAs and effects to create crossfading, mixing signals in a meaningful manner - all of this is such mental gymnastics at times (5 levels of mixers within mixers anyone) that it must develop some pretty essential cognitive abilities also on a more general level…

well, that got pretty far from LPF/HPF =)