How does CV behave in relation to the corresponding device Parameter knob?

Have an urge to learn, or a calling to teach? Want to share some useful Youtube videos? Do it here!
User avatar
deeplink
Posts: 756
Joined: 08 Jul 2020
Location: Dubai / Cape Town

Post 02 Jun 2022

Hi RT

A bit of a vague title, so let me clarify;

Take The Echo "Time" parameter in its milliseconds mode. As you may be aware, the smallest time you can achieve is 1ms when the knob is at say 1 (or 1/127).
When you move the knob slightly, it jumps to 8ms. Then 16ms etc.
This means you cannot dial in say 7ms or 10ms of delay on this device.

My question is, are you able to access those timings by using input? Or is CV also bound to the 127 different values of a parameter, just like the user is?

Cheers
Get Combinators, ReFills and RS Giveaways at the Shared GoogleDrive: [deeplink] Open RS-Project

Bes
Posts: 780
Joined: 22 Feb 2017

Post 02 Jun 2022

the time delay of the echo seems to be stepped quantised values
you can use the combinator to assign the full rotation of a control knob to just values 1-5 of the time delay and you will see that you cannot dial in 7ms or 10ms on this device

User avatar
deeplink
Posts: 756
Joined: 08 Jul 2020
Location: Dubai / Cape Town

Post 02 Jun 2022

Bes wrote:
02 Jun 2022
the time delay of the echo seems to be stepped quantised values
you can use the combinator to assign the full rotation of a control knob to just values 1-5 of the time delay and you will see that you cannot dial in 7ms or 10ms on this device
So for clarity, even CV patched into the delay time will modulate the delay time at its associated stepped quantized values.

I then assume, looking at a device like Reason's Polar RE - that although there is knobs for "Semitones" and separately "Fine Tune", the back of the device has a CV input for "Pitch". This CV parameter must therefore be controlling a separate hidden pitch parameter that spans the whole range in fine tune increments.
Get Combinators, ReFills and RS Giveaways at the Shared GoogleDrive: [deeplink] Open RS-Project

User avatar
selig
RE Developer
Posts: 10150
Joined: 15 Jan 2015
Location: The NorthWoods, CT, USA

Post 02 Jun 2022

CV doesn’t control knobs, CV controls parameters and knobs control parameters. Thats how you can have three different knobs all controlling one parameter: pitch (Octave, Semitone, Cents). You can also have pitch bend controlling pitch, and external CV controlling pitch, and mod matrix slots controlling pitch. Pitch is the parameter.
Automation (and Combinators) control knobs.
As for The Echo, the CV modulates the parameter as always, which is smooth. It’s the knob where the ‘quantized’ values come from. So YES you can definitely get “in between” values from The Echo, you just won’t know the actual delay time unless you measure it and calibrate it to some value of your choosing. For example, with the CV trim set to “1”, a full 127 input gives you one “step” of the knob.

Meaning if the delay is set to 1ms, and CV trim is 1, then a full CV 127 positive gives you 8ms delay. I’ve not checked this across the board, but it gives you a starting point: a CV of half (64) gives you roughly 4ms delay time. I haven’t tested this beyond a few settings, but it SHOULD allow a fine tune control for the delay time in The Echo. Could be a great subject for my live stream today since it’s not that well understood in my experience!

Side note: CV is not limited to 127 discrete steps in Reason, internally it is floating point data. But knobs, just like with the delay knob in The Echo CAN be restricted/quantized to discrete steps depending on the discretion of the developer.
This is how a device like Selig Gain can output CV from the fader with far more resolution than 127 steps though it.is not going to read these values on the tool tip since the primary function is to control gain in decibels. And also note that even though a knob may display ‘steps’, the actual resolution may be higher than is able to be displayed. You would be able to know this if you automate the knob and can type in values you cannot achieve on the knob itself (not all REs do this FWIW).
Selig Audio, LLC

User avatar
deeplink
Posts: 756
Joined: 08 Jul 2020
Location: Dubai / Cape Town

Post 02 Jun 2022

selig wrote:
02 Jun 2022
CV doesn’t control knobs, CV controls parameters and knobs control parameters....
Thank you for the detailed explanation Selig. I had feeling CV worked differently but couldn't tell from what I was seeing.

I'm keen to see what you may add in your livestream later.
Get Combinators, ReFills and RS Giveaways at the Shared GoogleDrive: [deeplink] Open RS-Project

User avatar
moofi
Posts: 806
Joined: 19 Jan 2015
Location: hear

Post 02 Jun 2022

CV routed to the Control input of the combinator actually controls the combinator knob, turning the incoming CV into a MIDI-value between 0-127, reason you get a different result compared to directly routing the CV-Combinator input to a parameter, where then CV resolution is applied. Wether the parameter supports CV-resolution is a different matter.
selig wrote:
02 Jun 2022
CV doesn’t control knobs, CV controls parameters and knobs control parameters. [...]

User avatar
moofi
Posts: 806
Joined: 19 Jan 2015
Location: hear

Post 02 Jun 2022

Even though CV-resolution is higher than MIDI it is limited to what, 16k? Saying audio rate modulation creates artefacts, reason I endorse increasing CV-resolution to audio resolution.
selig wrote:
02 Jun 2022
[...]

Side note: CV is not limited to 127 discrete steps in Reason, internally it is floating point data. But knobs, just like with the delay knob in The Echo CAN be restricted/quantized to discrete steps depending on the discretion of the developer.
[...]

User avatar
selig
RE Developer
Posts: 10150
Joined: 15 Jan 2015
Location: The NorthWoods, CT, USA

Post 02 Jun 2022

moofi wrote:
02 Jun 2022
Even though CV-resolution is higher than MIDI it is limited to what, 16k? Saying audio rate modulation creates artefacts, reason I endorse increasing CV-resolution to audio resolution.
selig wrote:
02 Jun 2022
[...]

Side note: CV is not limited to 127 discrete steps in Reason, internally it is floating point data. But knobs, just like with the delay knob in The Echo CAN be restricted/quantized to discrete steps depending on the discretion of the developer.
[...]
You’re talking sample rate ‘resolution’ (samples per second), I’m talking level resolution (bits).
CV sample rate is 1/64th the audio rate, so it can be increased by increasing sample rate. At 44,100 Hz audio sample rate you have a CV sample rate of 689.0625 Hz. Considering the upper frequency limit is half the sample rate, the upper limit is 344.53125 Hz at the LOWEST. Audio rate is modulation is already possible in Reason, I provided audio rate CV outputs for my first RE almost 10 years ago now (has it really been that long?), so it’s up to the dev to support it (Pulveriser is another that supports audio rate modulation).
Selig Audio, LLC

User avatar
moofi
Posts: 806
Joined: 19 Jan 2015
Location: hear

Post 02 Jun 2022

Oh, didn´t know it does, then is there any source being able to output CV at audio rate?
Btw how about updating Gain to convert audio to CV? :-)
selig wrote:
02 Jun 2022
moofi wrote:
02 Jun 2022
Even though CV-resolution is higher than MIDI it is limited to what, 16k? Saying audio rate modulation creates artefacts, reason I endorse increasing CV-resolution to audio resolution.

You’re talking sample rate ‘resolution’ (samples per second), I’m talking level resolution (bits).
CV sample rate is 1/64th the audio rate, so it can be increased by increasing sample rate. At 44,100 Hz audio sample rate you have a CV sample rate of 689.0625 Hz. Considering the upper frequency limit is half the sample rate, the upper limit is 344.53125 Hz at the LOWEST. Audio rate is modulation is already possible in Reason, I provided audio rate CV outputs for my first RE almost 10 years ago now (has it really been that long?), so it’s up to the dev to support it (Pulveriser is another that supports audio rate modulation).

Bes
Posts: 780
Joined: 22 Feb 2017

Post 02 Jun 2022

heeey yeah thats right selig thanks for the reminder.
so using cv i can get to the parameter values between 1 and 16ms. cv is so good

User avatar
selig
RE Developer
Posts: 10150
Joined: 15 Jan 2015
Location: The NorthWoods, CT, USA

Post 03 Jun 2022

moofi wrote:
02 Jun 2022
Oh, didn´t know it does, then is there any source being able to output CV at audio rate?
Btw how about updating Gain to convert audio to CV? :-)
Pulveriser, Pulsar, Leveler, Thor all output CV at audio rate.
Thor also converts audio to CV, but no longer at audio rate obviously. Thor (and others) also process CV internally at audio rate via their mod matrix.
What specifically are you wanting to do?
Selig Audio, LLC

User avatar
moofi
Posts: 806
Joined: 19 Jan 2015
Location: hear

Post 03 Jun 2022

Bascially modulating audio with audio rate modulators. Though like noticed with INDSTRLZR it´s already apparent when using an outside LFO for modulation compared to the internal one.
selig wrote:
03 Jun 2022
moofi wrote:
02 Jun 2022
Oh, didn´t know it does, then is there any source being able to output CV at audio rate?
Btw how about updating Gain to convert audio to CV? :-)
Pulveriser, Pulsar, Leveler, Thor all output CV at audio rate.
Thor also converts audio to CV, but no longer at audio rate obviously. Thor (and others) also process CV internally at audio rate via their mod matrix.
What specifically are you wanting to do?

  • Information
  • Who is online

    Users browsing this forum: CommonCrawl [Bot], Trendiction [Bot] and 4 guests