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SEQUENTIAL/DSI => Prophet => Prophet Rev2 => Topic started by: naturecollision on January 09, 2019, 05:45:29 AM

Title: Expression Pedal input / CV input "slow"
Post by: naturecollision on January 09, 2019, 05:45:29 AM

hi,

I have several DSI synths, with all of them the pedal input reacts too slow for fast cv, if the wave I give it is more than about 20hz, it will just filter anything above, is there a circuit with a low pass filter after the CV/Footpedal jack? and can I remove it so I can maybe do filter FM with this input on all my DSI's? that would be kind of nice don't you think?

:)

Title: Re: Expression Pedal input / CV input "slow"
Post by: Razmo on January 09, 2019, 05:53:48 AM

Quote from: naturecollision on January 09, 2019, 05:45:29 AM

hi,

I have several DSI synths, with all of them the pedal input reacts too slow for fast cv, if the wave I give it is more than about 20hz, it will just filter anything above, is there a circuit with a low pass filter after the CV/Footpedal jack? and can I remove it so I can maybe do filter FM with this input on all my DSI's? that would be kind of nice don't you think?

:)

You can allready do filter FM via OSC1... it's called AudioMod... The Pedal/VC input is meant for expression control, not audio rate modulations like filter FM :) ... so yes... there must be a filter at the input. I think, that if you need to modulate at audio rates you will have to take a look at the PRO2 instead, as that was build for Modular interactions.

Title: Re: Expression Pedal input / CV input "slow"
Post by: panic on January 11, 2019, 03:23:15 AM

The manual of the P08 and mopho I pretty much know by heart, and they specifically mention that the CV-input is heavily filtered. No way of turning that off as far as I know. I suppose they kept the same design (though the filtering is indeed not mentioned in the Rev2 manual).

Title: Re: Expression Pedal input / CV input "slow"
Post by: Razmo on January 11, 2019, 04:23:54 AM

On top of all that, I doubt that the CV input is connected directly to any analog sound parts like the filter for example... it's most likely converted to digital for the modulation matrix, and the modulation matrix does not run at full audio rate anyway... pedal/CV input is available as a modulation source, so I think that in any case, without an analog filter on the input or not, it would not make much sense since the modulation matrix is running at a slow rate anyway. I bet the filter in the pedal input is calibrated so that no frequencies above the mod matrix's will be let thru.