A4 to guitar pedal cv?

Hello,
Yes, I know in order to control a guitar pedal from the A4, it has to have CV-in. But from what I can gather, both Strymon and Moog minifoogers expression inputs can be used as CV.
I am, however, new to CV and have been trying to wrap my head around how I can use the A4 to control the minifooger ring modulation pedals pitch while playing guitar. It would be great if this was possible, since dialing in any kind of accurate ring mod pitch with a foot controller is hit and miss. I was thinking it would be possible to trigger various pitches on different patterns to stay ā€œin tuneā€ with the music. This would solve a huge problem for me, as Iā€™m playing guitar and using the A4 simultaneously.
Does anyone know how to do this, and if so, are you capable of explaining in simple terms how I need to set up the CV?

Letā€™s assume that the device can be controlled by CV and is set up correctly (all of that is your job to check through)

You have 4 channels of CV output on the A4 and you have two tracks usually spare to use, but you donā€™t even need to use those, but FX track and CV track can be used for events and maybe pitch

So, CVA CVB CVC CVD can be set up to be many types of control voltage event BT for your needs you want to have access to Value Lin

Configure CVA to send Value Lin, set the Lower and Upper range to 0v and 5v (for starters)

Now CVA is there waiting to be scaled between 0 and 5v using a signal from the A4, you can use an envelope or LFO from the respective track controlling the voltage or even trig events or parameter locks of the Value CVA directly set on a step

It all depends on what shape and type of signal you want to transmit to your effects

If you want to send info linked to pitch on a 1v/Oct basis, then set up a CV channel as V/Oct instead of value lin, this way the pitch info you generate in the track (or borrow from another track) will be translated to the equivalent voltage

If you are just controlling a predetermined set of values then you can easily just dial in values using Value Lin, itā€™s basically just like an encoder, you determine the range beforehand and turn the dial to taste

When the Value Lin is chosen, you will be presented with one dial, you just plock this per step as you would any other parameter, or the specific Value Lin value can be selected as a target for LFO or Env

Best just explore with low voltages to begin with and keep in mind the A4 is capable of sending out +/- 10v which your gear may not like

If you are using a Mono cable (as opposed to TRS insert type cable for CV output) then just use the Tip signal channel and ground the other channel (CVB)

If you need fine control of the voltage level it may be better to use a square LFO set to Hold mode, this will output a value of 1 in the range -1 or 1 then use the LFO depth to adjust the value, the LFO depth value is 14bit iirc (but itā€™s much finer than the Value Lin dial directly)

Also note where the Value Lin dial is set, it wild act as an offset, so you may want to zero the voltage on the dial before applying modulations via env or lfo

donā€™t do anything youā€™re not confident about, or at least start with Value Lin set to a lower voltage range than needed

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Wow, thank you for the detailed explanation. Will follow your advice to the letter.

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With Analog Heat, should be cool too. :wink:

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The MF line of pedals all accept +5V, I have the Boost connected to A4 CV and use it as a pseudo side-chain effect. Using a linear value and a tempo synced sine or saw wave lfo that creates a great pumping sound!

On the Moog site they state that the expression control is additive and can go beyond the front panel controls, so donā€™t be worried if you hear wilder tones coming from it!

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Cool, thanks!

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Hey, Avantronica.
I finally got to try it out tonight, and it actually works :-o I can now program the pitch of the ring mod on various triggers and play along with my guitar. Makes the minifooger actually usable.
Thanks again for the help!

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Necroing this thread to ask a question:

I have a pedal that expects a TRS expression pedal signal, but the manual says that also CV (0-5volts) can be used instead. However, since the A4 transmits two discreet CV signals via a single TRS CV output, what interconnect cable should I use to connect? Or do I just use two CV outs with identical output signals and just use a normal TRS-TRS cable?

Iā€™m used to using only TS interconnects for CV, this is slightly confusingā€¦

Itā€™d operate as a voltage divider if it was an expression pedal

Given that you can dial in the max and min to the A4 and vary this, thus you donā€™t need the A4 to act like a voltage divider, you can cut the middle man out and just return the correct voltage to the correct pole of the TRS jack

My hunch is that a TRS on A4 set on either TS>TS or TR>TS will be sufficient

Either way, if you feed a TS into the pedal, the non-present ā€˜ringā€™ (supply voltage) will be grounded and the returned voltage at the tip will be the expected ā€˜dividedā€™ voltage (the important bit)

I think youā€™ll find answers on the internet (check for your pedal of course), Iā€™ve definitely done this exact thing before - so you only need to use one channel of A4 CV to do the deed, using value lin as explained above ā€¦ Iā€™m guessing the pedal will not object to a TS in place of the TRS

ymmv

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sweet!

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Thanks for doing so - itā€™s reminded me to try something similar with the expression pedal input of my EHX Memory Boy - especially with the Erebus to double up on the built-in delay possibilities.

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Thanks too. Not sure Iā€™ll use it but I have a midi foot controller with exp pedal inputs, converting it to midi.

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If I want to use guitar pedals with my Analog 4 MK2 without CV, how would I do this on the Analog 4? I have tons of guitar pedals that Iā€™d like to make use of besides on my pedalboard.

Hey, Carl Mikael answers that in this video :slight_smile:

Cheers!

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what happened to Carlā€™s beard and hair? He used to have long hair and a massive beard that made him look a Viking!

Anyone using CV from their A4 into a Chase Bliss pedal? Iā€™m trying to sync mine (Chase Bliss Tonal Recall). Iā€™ve got the proper cable, I have the ring grounded, but Iā€™m not sure if I should set the tip for clock, or trigger (I just want to sync the Tonal Recall repeats to the A4ā€™s tempo).

Trigger, I think. To sync the pedal I would sequence triggers. When I tried the clock out on my AK it was just one pulse at the top of each measure.