CV Out value

[wilkinsi]

I want to use the CV Out to send commands from the expression pedal to my Eventide H9, but I don't know what value to use. I read the H9's manual:

 

"An external Expression Pedal can be connected to the rear panel 1â„4†stereo phone jack labeled “EXPâ€. The Expression Pedal can be set up to control any combination of parameters. For proper operation the Expression Pedal should be a simple linear taper resistive potentiometer (“potâ€) with a maximum value of between 5k Ohms and 25k Ohms. Refer to www.eventide.com for information on recommended expression pedals."

 

So, 1) is the built in EXP pedal on Helix compatible, and 2) what do I change the CV Out value to? I don't want to damage anything.

 

Thanks.

 

[CraigGT]

I don't know any detail about the H9 but expression pedal jacks are usually 5v tip and ground sleeve and so the pedal delivers between 0 and 5v on the ring.

 

Try a straight trs cable between the two and see what happens. I can't imagine it doing any damage.

 

Craig

[jbuhajla]

If the H9 is expecting to see an expression pedal pot, I would not connect the Helix CV (control voltage) out to it. Expression pedal is a potentiometer (variable resistor), CV out is an analog voltage (0-5vdc). They are not the same thing. 

 

You should be able to control the H9 via midi from the Helix. 

[CraigGT]

Yes the H9 might be expecting to see a pot but it's highly likely that it's using it as a potential divider and so the result is exactly the same as a 5V CV signal.

I know that Strymons work this way.

 

Craig

[phil_m]

Yes the H9 might be expecting to see a pot but it's highly likely that it's using it as a potential divider and so the result is exactly the same as a 5V CV signal.

I know that Strymons work this way.

 

Craig

The difference is that with CV, the expression pedal or controller is providing the voltage. With a passive expression pedal, the pedal being controlled, the H9 in this instance, is providing voltage to the expression pedal. In the lighting world we use the terms "source" and "sink" when talking about different controllers. CV is like a source-type controller, and a passive expression pedal is like sink-type controller.

[CraigGT]

I know where you are coming from but from page 25 of the H9 user guide

 

"Note: The Expression Pedal input supports control voltage inputs from 0V to 3V"

 

It looks like you'd need a ts to trs cable though not trs-trs as I stated earlier.

 

Craig

[phil_m]

I know where you are coming from but from page 25 of the H9 user guide

 

"Note: The Expression Pedal input supports control voltage inputs from 0V to 3V"

 

It looks like you'd need a ts to trs cable though not trs-trs as I stated earlier.

 

Craig

 

Yes, if you short the voltage source coming from the H9, which is what the TS plug would be doing, you can then can use the CV from the Helix...

[CraigGT]

So I've been having a play with this.

The CV out goes from 0-5V when set to a max CV of 100% and a max of 60% gives 3V as required by the H9.

 

I just connected a trs cable between the CV out and expression in on a Strymon pedal and it worked straight away.

 

Craig

[HonestOpinion]

So I've been having a play with this.

The CV out goes from 0-5V when set to a max CV of 100% and a max of 60% gives 3V as required by the H9.

 

I just connected a trs cable between the CV out and expression in on a Strymon pedal and it worked straight away.

 

Craig

 

Good info to have, thanks!

[wilkinsi]

Thanks. I think I will just stick with trying to control it via MIDI.

[jbuhajla]

So I've been having a play with this.

The CV out goes from 0-5V when set to a max CV of 100% and a max of 60% gives 3V as required by the H9.

 

I just connected a trs cable between the CV out and expression in on a Strymon pedal and it worked straight away.

 

Craig

Nice!