Thursday, 15 August 2019

Creative Limitations - Where to Start When There Are too Many Choices

From time to time, I find a question on a Facebook group that gets me going on an answer. While it might only take a few minutes to write out the answer, I look back at it and I say to myself that it would make a good post on this blog. At least I can keep a record of my thoughts if nobody else reads it.

The question this time was regarding the situation of what to do when there are too many choices and no idea of a starting point. This generally happens when people do not know how to fully use the equipment they have. I know because I have more equipment than I know how to use at this time. I am currently in the process of learning how to use about three synths and that is enough to get a surprising amount of variation in my music.

Ideally, you should learn how to use each piece of gear before you buy another piece of gear. This is often not the case and many a musician will complain of Gear Acquirement Syndrome - GAS! I believe the root of GAS is really lack of discipline in learning how to use the equipment you have. To put it bluntly, laziness. The effect of this lack of discipline is making music that is not up to your expectations and when that happens, people often look at other people's gear thinking that their equipment might allow you to make the music you want to be able to make.

This brings us, you the reader, and me, the writer, to the point of asking the question of what to do next? Read on, "salvation lies within" (a little quote from one of my favourite movies, The Shawshank Redemption).

Try paring it down to three synths and see what you can do. If you do not have room, store the rest in a closet or somewhere safe. Once you think you have working those three synths down, push your creative boundaries or set some limitations so you can make some new stuff. At that point, you have to imagine that you are still limited to those three synths. Resist the urge to bring another synth back into the mix. By the way, learning those three synths means learning how to use each synth in its entirety, not just making one patch and how to use that sound in one song.

You might need to learn about subtractive synthesis in general. Or, maybe your synth is an FM synth. Maybe you have a sampler or it is a sequencer you are trying to use. So, yes, learn your synths in general, but all the other equipment needs to be learned as well. Effects pedals and guitars also fall into the range of your equipment so it does not have to be just your synths.

Once you can focus on your work to get beyond the idea that you have too many choices by making yourself accomplish the work with those three synths, add another synth. The end goal is to be able to form a basic idea and build it up.

Three synths is just a creative limitation. You might have read how some bands will give themselves creative limitations for an album. It helps you to limit your choices and be creative within that framework.

Once you create enough, you will understand how to use all that you have and not be bogged down by choices. This is a truth and essentially masters do it in all arts and sciences. People work with their tools so much that they understand how to use everything.

The image I have in mind as I write this is the YouTube videos on Junkie XL's channel. Have a look at his Studio Time series where he shows different synths that he uses. If you gave all that stuff to a noob they would have no idea where to start unless they picked just one thing. Yet he uses it all and he knows what each thing can do. I also imagine that he can make very new sounds using all of the equipment.

Saturday, 8 June 2019

In Reaction to a YouTube Video on Plagiarism

This post is in response to a video on YouTube titled "Inspiration vs Plagiarism," by Red Means Recording.

Here is the link if you would like to watch it:
Inspiration vs Plagiarism

There were a couple of versions of this post before this version and I might pull in some other thoughts from the other versions. The main part of this version comes from my daily morning writings that help me get started with my day. The writing exercise is not something I came up with on my own. It is something I read in a book called "The Artist's Way," by Julia Cameron. The actual exercise is to make the first thing you do in the day to write at least three pages of material. It is meant to help get your creative juices flowing. I actually have breakfast first but the spirit is still there.

These daily writings actually help a lot. I write about many different things but a lot of it ends up being what is on my mind. It helps to get those thoughts on paper instead of allowing to continually rattle around up there causing noise. I also make an effort from time to time to write about project ideas I have in an effort to be more productive. Enough about how this post was written and onto the post itself.

This topic of plagiarism is really occupying my mind. I cannot let it go. I think that reason I cannot let it go is that the same day that I saw Red Means Recording on YouTube on his experience with another YouTuber copying his style, I saw somebody use my tutorial to make a sound on their Korg Volca Keys synth video. They posted their short video on Facebook and did not give me credit.

On the one hand, I even said that tin the tutorial that the graphic can be used as a template for recording patch settings for the Keys. There is no patch memory on the Keys.

In many places, I have given credit to Tony Horgan for his book on the Keys. I have used it to help me understand how to use this synth and to double-check what Keys controls actually do. I still give him credit in ways such as citing his book as a good resource on how to learn about the Keys.

It took me about one week to write the tutorial. I put a good amount of effort into it between writing, drawing graphics in LibreOffice Writer, and recording audio clips.

In hindsight, it might have been better to let the Facebook post in which the guy used my graphic to sit without my comment. He may have gotten more comments which could have possibly lead to more people eventually finding my tutorial and blog. I suppose it is not in my nature to do so.

This morning, I took the time to watch one of Red Means Recording's videos where he uses the Teenage Engineering OP-1. I watched it all the way through. Now, after writing this, I will watch one of Yuri Wong's videos using the OP-1. I need to watch a whole video before I make another comment to Red Means Recording. --- So, I watched a couple of Yuri Wong's videos.

My current opinion, based on what I have seen so far, is that Yuri Wong has definitely copied Red Means Recording's style. Whether or not that is actually plagiarism might be for an expert to decide, not me.

If I were to make such a video, I would definitely change things enough so as to be stylistically different. In the end, I would most likely give some credit to Red Means Recording just because of his influence on my work.

YouTube videos such as these are still fairly new in terms of making media. There is a lot to be explored and the ability to create quality videos has become easier with both proprietary and free and open source software. I tend to use the free and open source stuff because it is also monetarily free but, it also promotes education to the masses. Check "free and open source," "FOSS," "creative commons," and more out to see what I mean.

My point in bringing up the software is that these YouTube videos are produced using tools of software. It is most likely not the most popular opinion among many creative types, but copying a style might not necessarily be plagiarism. In the court of popular opinion, those in the know about both Red Means Recording's videos and Yuri Wong's videos, and whose came first (Red Means Recording's if you were wondering), will likely consider it copying. It is most likely considered distasteful among other things but I do not want to get into that.

By the way, in my tutorial located here: Sound Design - Getting the Wah Using the Korg Volca Keys, at the end of the tutorial, I use the sentence "Share the knowledge!" This imperative is a shortened version of YouTuber, Ricky Tinez's phrase of "Share the love, share the knowledge. Knowledge is power" which he uses near the end of his videos. I like the phrase I use at the end of my tutorial but, it never really quite sat well with me because he was using it. Some people might not realize it, unless you are of a certain age, but a version of that phrase used to be at the end of... what was it, Saturday morning cartoons, maybe, a good number of years ago?

My next tutorial ended with something I came up with myself: "Take time to help people out. You will thank yourself later!" Whether or not that works out for me as an ending, time will tell.

Last Thought:
Does Yuri Wong actually give a nod to Red Means Recording when a caption in one of his videos says "Recording to Red," or is it a slap in the face? My first impression on that was a nod to Red Means Recording. Maybe that is the best thought to have.

Saturday, 11 May 2019

Designing a Wah Sound Using the Roland SH-01A

The previous tutorial on synthesizers was about designing a wah-type sound using the Korg Volca Keys. Somebody had requested some help in getting that sound in a group on Facebook so I took up the challenge and learned a lot in the process. If you want to learn a lot about designing sounds, trying to emulate somebody else's sound or sounds is a great way to learn.

My recommendation is to listen to the sound before trying to produce it. Lots of people use other people's presets and that is great. It can help a lot I imagine because you get the settings used as well as the sound itself. It would probably help a lot if you listen to your newly designed sound and sensed that something was missing. Then you could go look at the settings in the preset and figure things out from there.

Anyway, read on for how to get a that wah sound from the Roland SH-10A. If you want to find material about why the synth is working the way it is, you can read the other tutorial here:
Designing a Sound Using an Example from a Song – Getting the Wah Using the Korg Volca Keys

Reading the previous tutorial is not necessary. If you do, there are certain sections that you will probably like to check out if reading that tutorial.

Here is a list of sections that will help you understand the tutorial, especially if you do not have a Korg Volca Keys to use (simply scroll down and you will see these parts):
1) Diagram of the Korg Volca Keys - useful for the layout of controls. It is the second diagram.
2) So, What is a Filter Sweep? - under this section it explains what a filter sweep is, the thing that makes a wah sound.
3) ADSR Envelope under the previous section.
4) Working on Wah or Filter Sweep - See the altered ADSR diagram.
5) LFO Applications affecting the Low Pass Resonant Filter, the VCF - see the two diagrams on the LFO Cutoff Int affecting the Low Pass Filter

The Steps:

The SH-01A is laid out in a very straightforward fashion. I did not feel the need to record sound clips for this tutorial.

Here are the steps for getting a wah-type sound from the SH-01A:

Step 1: Slide all controls to zero.
Set VCA Env/Gate to Env.
Set Gate+Trig/Gate/LFO to Gate+Trig
Set LFO Waveform to rising saw wave.
Set Transpose to M.
Set Portamento switch toOff.
Pitch control is in the middle.
Sub Osc is set to 2 Oct Down but it makes no difference because we are going to use the Sawtooth oscillator by itself.
Even though single notes are being played, my SH-01A is set to Poly so I can play up to four notes when I want.
LFO section beside the control that selects the LFO waveform are three small sliders. Set them all the 0%.

I do not think there are Menu settings other than setting the synth to Poly that affect anything. If you are not getting what is expected from your SH-10A, back up your synth then reset it to factory settings.

Step 2: Slide the Sawtooth oscillator up to 100%. Set the Volume to an appropriate level.
Play notes and you should get no sound. I get no sound.

Step 3: Set VCF Freq to 50%.
Play notes and you should get a bassy pop.

Step 4: Set ENV Attack to 25%.
Play some notes. You should get a short note that does not plucky. The notes ease into maximum volume.

Step 5: Set Decay to 50%.
Play some notes and you get a note that rises and falls in volume.

Step 6: Turn up Res to 100%.
Play notes and get a tone that tracks with notes being played. There is also a self-oscillation in the filter. It does not track with the notes being played. (NOTE: Later, you can turn up the Kybd setting under VCF and the self-resonating filter will track with the notes being played. The tutorial used Kybd at 0%.)

Step 7: Turn up VCF Env.
Play notes as Env is turned up and the wah sound really starts to be heard.

Step 8: Record a sequence and play it back.
Tweak to your heart's content.

Take time to help people out. You will thank yourself later!

Sound Design - Getting the Wah Using the Korg Volca Keys

Here is the next tutorial involving synthesizers. This one explores how to make a wah-type sound using a Korg Volca Keys. Along with the previous tutorial released recently, I am trying a new format. You get the summarized steps at the top of the tutorial which will direct you in the shortest way I know how in getting the results of the tutorial's purpose.

By the way, if you think about things a little bit and try to match up the control knobs between the Korg Volca Keys and the Roland SH-01A, you can get your wah-type sounds there as well. This should work for just about any synth that uses subtractive synthesis, analog or virtual analog. I will post the steps for getting the way-type sound on the SH-10A in another post.

Please read on below because there is a lot of information to help you understand what is going on when you turn the knobs and use the controls of the synth. Sound clips are provided in the more detailed section. Enough with explaining the why and how...

Here we go!

HINT: All of the knobs on the Keys that are clear, except the VCF Peak and the Tempo knobs, light up when you turn them. That can help when figuring out the notch indicator is on them. The Peak does not light up at all. Tempo lights up in time with the tempo.

Step 1: Turn every control hard left. LFO is Tri, Trigger Sync is on, Step Trigger is on. Turn up the volume to something appropriate. Play notes and get a short bassy pop.

Step 2: Turn VCF Cutoff to 12 o'clock.
Play notes, get a short note that tracks with the note being played on the keyboard.

Step 3: Turn EG Attack to 9 o'clock.
Play notes, get a short note that eases into its maximum volume.

Step 4: Turn EG Decay/Release to 12 o'clock.
Play notes, get a slightly longer note that tracks with the note being played up and down the keyboard.

Step 5: Turn VCF EG Int to hard right.
Play notes, the notes are not as muffled. They are fuller sounding.

Step 6: Turn VCF Peak hard right, playing notes as Peak is turned higher.
Notes do not change much, to my ears anyway, and at the high range of Peak, a high pitched noise sounds.

Step 7: Ease back on VCF Peak. Play notes as doing so until the high pitched squeal disappears. That happens about 4 o'clock.

Step 8: Slowly turn up LFO Cutoff Int and listen to the notes you play.
The wah sound slowly occurs and then becomes more pronounced as Cutoff Int increases.

Step 9: There is a wah sound. Take note though, you can tweak this sound even more.

Step 10: Turn VCF Peak to the right as you keep playing notes. The wah sound becomes even more pronounced without the filter self-oscillating to the point where it becomes a high pitched squeal. I think this is because the Cutoff Int is higher so the roll off on the Cutoff frequency is sharper, reducing the higher end harmonics - in my opinion, thoughts, etc.

Step 11: Record a simple melody on the sequencer. Run it and now turn up the Decay/Release and listen to how it changes. Definitely some interesting changes. Use motion sequencing if you want to experiment and have some fun. Hint: Try smaller changes.

Step 12: Make sure motion sequencing is off at this point. Slowly increase Sustain and listen to the notes get longer in duration and fuller in sound. Try using the LFO Rate and Sustain for sounds approaching distortion in quality of timbre.

Now for the explanation:

Somebody asked a question on a group on the Web about how to get a particular sound that they had heard in a song. They provided a link to a video of somebody playing their song so the sound design could be heard.

I have been playing with synths for about five years but only within the last year or so have I started playing with synths and designing my own sounds. It is a lot of fun to do and make music with those sounds.

Using other's sounds as examples of something you want to use in your music is a great way to learn about synthesis. We are going to use the Korg Volca Keys to design the sound as that is what was used in the video. However, it should work the same way for any analog synth using subtractive synthesis.

Shows 12, 3, 6, and 9 o'clock positions
To the left is a clock face showing the 12, 3, 6, and 9 o'clock positions. This will come in handy later for referencing where to turn the controls when changes are made.

Using MIDI keyboard controllers

If you have a MIDI keyboard controller, you can use the controls on it to control the Keys. After I had finished making all the sounds for this tutorial, I mapped the controls for my Oxygen 49 Blue version to the Keys. I was already using the controller to play the keys and now I wanted to use the controls on it. The Oxygen 49 Blue has nine sliders and eight knobs among the buttons. I just mapped the sliders and knobs.

The issue of translating knobs on the Keys to sliders on the Oxygen 49 or any other keyboard controller with sliders is knowing how far the knobs go on a clock face. My best estimate comparing knobs on the Keys, Oxygen 49 and an Akai MPK Mini II is that knobs go from approximately 7:30 or 8 o'clock at hard left to 4:30 or 5 o'clock at hard right. On a knob, 12 o'clock is 50% or halfway of the slider's travel. Those are your guidelines for estimating positions between knobs and sliders.

If you are having a hard time comparing the Keys knobs to your controller's sliders, check the controller's knobs and sliders extremes. The controller's knobs are likely larger and easier to see.

Below is a representation of the Korg Volca Keys. As you can see, it does not have all the features on it. I put the ones needed for this tutorial. Missing are the power button, power jack, MIDI In jack, Sync In jack, Sync Out jack, and headphones jack. You could copy the representation below as a template for a patch sheet for the Keys are it has no memory for storing patches.

Korg Volca Keys

I have to admit, I do not try to imitate other people's sounds much so this will be an exercise for me.

Where to Start? 
The steps as summarized begin below. First I explain about picking out the sound from a piece of music.

The first thing to do is listen to the music to determine what sound it is that you are trying to emulate or imitate. The original post was using this YouTube video as an example: 

Click below to see and hear the example provided as a reference:
Example of Music

If that link does not work, do not worry. You can take just about any other piece of music that uses an analog synth with a wah-type sound as a reference for this tutorial.

The issue I have with listening to music is being able to isolate the different sounds to the point where I can definitely say that there is one particular instrument making that particular sound. Music is a blend of sounds, some more distinct than others. Some play the same melody as others and there are all kinds of different interactions. Before you go about emulating a specific sound, take some time to listen to the music first to pinpoint the specific sound.

In the video above, I listen until about the 1:10 (m:ss) mark where I can hear the Keys making a sound and it changes into something with a wah-type timbre to it. That is the sound I am going to focus on making.

One thing to note about wah-type sounds is that they wah from somewhere. That means to get there, you have to come from somewhere. There is a beginning point even if in the music the sound is always changing. It does not always have to change but it can. That means we have two sounds, in a sense. We have a base sound and the sound that is changing to make it the wah-type sound.

To make this a little more clear, in the video around that 1:10 mark, you can see the person changing some controls in what looks like the VCF section. That is good because a wah sound is a filter sweep.

Step 1: Turn every control hard left. LFO is Tri, Trigger Sync is on, Step Trigger is on. Turn up the Volume to something appropriate. Play notes and get a short bassy pop.

Starting from Zero

For fun to see where this goes, turn all the knobs hard left, everyone of them on the Keys, from Voice to Detune to Time and Volume. An alternative would be to set everything at 12 o'clock and adjust things from there. When you play notes now, you should hear nothing. See the diagram above with all the controls set to hard left. Now we are going to make some changes from zero.

Here is a representation of the capacitive keyboard on the instrument.You can use it for reference when looking at the settings to change on the keyboard as given later.

Capacitive Keyboard Labelled

There are some keyboard settings to be used. If you use different settings, you will get different sounds.

LFO: set the LFO waveform to TRI. Press and hold the Func button then press the Tri key in the LFO section on the keyboard. The LED for Tri should now be lit.

Trigger Sync: To turn on Trigger Sync press and hold the Func button and press the Trigger Sync key on the keyboard. The Trigger Sync LED should now be lit.

Step Trigger: To turn on Step Trigger, press and hold the Func button and press the Step Trigger key on the keyboard. The Step Trigger LED should now be lit.
Voice and Octave
The Voice control should be set to Poly and the Octave control should be set to 32'. If you are using a MIDI keyboard or something through your computer to play the Keys, the Octave knobs should not really matter. Turn up the volume to something appropriate. Play some notes and you should hear a bassy pop.

Click on the link provided below to hear what it should sound like:
Bassy Pop

Step 2: Turn VCF Cutoff to 12 o'clock.
Play notes, get a short note that tracks with the note being played on the keyboard.

VCF, Voltage Controlled Filter
In the VCF section, turn Cutoff up to 12 o'clock. Now play some notes and the pitch of the note will sound appropriate for the key being played. The notes should sound very short, quite like staccato even if the next key being played is being pressed down while the previous key is being released. Attack is very short so the notes sound immediately and all other envelope generator (EG) settings are set to zero so there is no sound past the initial quick burst.

Cutoff Frequency at 12 o'clock
                        Click the link to the sound file below to hear what the Keys should sound like now:

VCF Cutoff at 12 o'clock

For now, we are going to be focusing on playing one note at a time to be able to hear the sound of only the one note. It makes it easier to realize what is going on with the sounds you are hearing. There are lots of situations where playing three notes on the Keys is needed, but not here.

There are different ways to approach sound design. Some people take another person's preset (the presets that come on other synths were made by a person) and tweak the controls until they get something different from the original which they like. Other people design sounds from the ground up. They can start with the oscillators and work with a particular goal in mind and they usually follow a specific procedure, such as working on the envelope generator next, then the filter section, the amplifier section, etc. Both approaches work and have merit.

Tweaking presets and studying them as you tweak them allow you to understand them that way. Working from the ground up allows you to work with the sounds in a way where you understand individual synth sections and the effects they can have one at a time. There can be combinations and the two are not mutually exclusive. That means both approaches can have similarities and work flows. You just have to try both to see what works for you. There is nothing to stop you from working with one method one time and using another method another time or changing between.

Using both approaches might include taking a preset and turning all the controls hard left except for one section such as the envelope generator section. Then you can build up a preset from zero with all the rest of the controls.

Again, we are going to start from zero.

So, now you can see that there are different methods and we are starting from zero. We have opened up the filter a little so that the Cutoff allows more than just the lowest bass frequencies through. But, what I want to express is that you can put some real thought into sound design. Above, I mentioned that a wah-type sound is a filter sweep. How do we accomplish that on the Volca Keys?

My take on the Volca series of synths is that Korg has worked on providing synths or grooveboxes, in an affordable form factor that give the musician the most value for their dollar. This means that they have designed the Keys in such a way so that controls can be used for more than one purpose. The EG or envelope generator section is always applied to the oscillator amplitude. That means that the volume of the oscillator is affected by the envelope. The EG can also be applied to the frequency of the oscillators and the cutoff frequency of the the filter. This is good because now we can look at how to do a filter sweep on the Keys.
So, what is a Filter Sweep?

So, a filter sweep or a wah sound is what happens when a filter changes its cutoff freqeuncy up or down.

With a filter sweep, in my opinion, you want to be able to hear any effects immediately for the most punch. That is subjective, so take it as you will. In the end you are creating a sound so it is up to you to decide. Set the goal to hear the filter sweep immediately. Let us have a look at a typical envelope below.

There are four parts to an ADSR envelope. For some reason, it was the sustain part that eluded me in its true meaning for the longest. We will get there in a minute. Let us use an ADSR applied to the volume of the amplifier section of a synth.

Attack: This is the time it takes for the note to rise in volume from zero to its highest level. At its highest level it meets where the Decay starts.

Decay: This is the time it takes from where the Attack leaves it at the high level to go to the level at which the Sustain level is set.

Sustain: Sustain is different than the other controls in an ADSR envelope. Sustain is always at the same level. When a note is played, if the note is held long enough to get through the Attack and Decay portions of the envelope, the note will sound as loud as the level set by this control. When the note is released the Sustain portion ends and Release begins.

Release: This is the time it takes for the note to lower in volume from the level set by Sustain to zero.

What was just explained was how the ADSR envelope affects volume. However, an ADSR envelope can affect other controls such as the pitch of one of the oscillators (or more) or the cutoff frequency of frequency of a low pass filter. The Keys has the ability to both of those things by the use of the EG Int control under the VCO (Voltage Controlled Oscillator) and VCF (Voltage Controlled Filter) sections. We are going to use the EG section on the VCF Cutoff Frequency. Decay and Release are controlled by the same knob on the Keys.
Working on Wah or Filter Sweep
The wah sound will be heard more effectively when there is no sustained frequency level between when the note reaches its peak and zero. Remember, we are now applying the envelope to frequency. That works, at least in theory. What this means using the diagram of the ADSR envelope above is eliminating the Sustain portion. The diagram below is what that looks like.

Take note that because Sustain is at zero, Release no longer affects the sound.
ADSR Envelope, Sustain at Zero

Using the diagram of the ADSR envelope above, with the Sustain set to zero, we get a filter sweep that goes up and down. Now we can move on to making the changes to the controls to make a filter sweep or wah.

Step 3: Turn EG Attack to 9 o'clock.
Play notes, get a short note that eases into its maximum volume.

Set the Attack at 9 o'clock.

Click the link below to listen to how that sounds:
EC Attack at 9 o'clock

Step 4: Turn EG Decay/Release to 12 o'clock.
Play notes, get a slightly longer note that tracks with the note being played up and down the keyboard.

Turn Decay/Release to 12 o'clock.
Sustain stays at hard left or zero.
Play some notes at this point and it is not all that exciting in terms of sounds. Actually, it does not change much at all as the note plays.

Click the link below to hear the results:
EG Decay/Release at 12 o'clock

Step 5: Turn VCF EG Int to hard right.

Play notes, the notes are not as muffled. They are fuller sounding.

Waht we need - see that! Waht we need is the filter sweep to have an effect. Under the VCF section, turn the EG Int control all the way up, or hard right. Now the tone is not so muffled. What has happened is the envelope affecting not only the amplitude of the note, but the Cutoff frequency of the note as it plays over the time it sounds. With EG Int hard left, there is no variation in Cutoff frequency.

Click the link below to hear what the Keys should sound like now:
VCF EG Int at hard right

Step 6: Turn VCF Peak hard right, playing notes as Peak is turned higher.
Notes do not change much, to my ears anyway, and at the high range of Peak, a high pitched noise sounds.

VCF Peak at hard rightNow we can use the the VCF Peak control to increase the frequencies around the cutoff point. Turn the Peak to hard right but, as you do so play some notes. You will start to hear a pronounced wah sound. Near the end of turning Peak to the hard right, the filter will start to self-oscillate. That means you should hear a high pitch. In this case the note you play also plays and the self-oscillating pitch tracks with the note being played.

Click on the link below to hear what that Keys should sound like now:
VCF Peak at hard right

Step 7: Ease back on VCF Peak. Play notes as doing so until the high pitched squeal disappears. That happens about 4 o'clock.

VCF Peak at 4 o'clock
Turn the Peak back to about 4 o'clock  which is approximately where the self-oscillation of the filter stops with these settings. Play some notes now and now you should really hear a decent volume sound. Turning up the Peak control has increased the amount of frequency volume at the cutoff point of the filter. There is a filter sweep but not quite a wah sound yet.

Click on the link below to hear how that should sound:
VCF Peak at about 4 o'clock

Step 8: Slowly turn up LFO Cutoff Int and listen to the notes you play.

The wah sound slowly occurs and then becomes more pronounced as Cutoff Int increases.

LFO Applications affecting the Low Pass Resonant Filter, the VCF

In many cases on a synth, the LFO affects the volume of the notes being played. The Keys allows volume to be affected using the Envelope Generator. Looking at the Keys manual, you can see that the LFO can affect the filter and the pitch of the oscillators.

Korg provides the PDF of the owner's manual on their website. You might find it easier to read as a PDF by enlarging it in a PDF viewer. The easy way to enlarge a PDF is to use the shortcut key, Ctrl- + (Linux and Windows) or Cmd- + (MAc OSX). Use Ctrl- - or Cmd- - to reduce the size. This also works for webpages so if you need to enlarge this post to read it more easily, do the same.

We still have the VCO EG Int set to hard left, or zero, so no modulation or variation in pitch is used at this point.

Even though Pitch Int will produce an effect in the VCO, even though VCO EG Int is set to hard left, we do not want to use that here. So, not Pitch Int.

The control we want to use to affect the filter sweep if LFO Cutoff Int. Turn it hard right. As you turn it, play some notes to hear its effect on the sound.

Click the link below to hear how the Keys should sound at this point:
LFO Cutoff Int hard right

My best guess as to why the sound becomes muffled at the end of the clip for this step is that Cutoff Int has become so much that the Cutoff frequency is dropping sharply so the higher frequencies are not heard so much. The harmonics have been attenuated. You can look that up, but suffice it to say when you play a note on any instrument, you will hear not just the frequency of the note being played. There are other frequencies that occur above it.

Here is an example of the filter effects. The frequencies before the Cutoff frequency are heard. There is a Peak around the Cutoff frequency. The amplitude decreases after the Cutoff frequency.
Typical Frequency Response of a Low Pass Resonant Filter

The diagram below shows the Cutoff frequency and Peak with a different shape than the diagram above. The slope after the Cutoff frequency and Peak also drops much more sharply. Without using an oscilloscope and the math, this is what I imagine is happening to the VCF.

Cutoff Int Set Hard Right
Try turning Cutoff Int back to 1 o'clock or 2 o'clock to see if you like that sounds any better.

Step 9: There is a wah sound. Take note though, you can tweak this sound even more.

Step 10: Turn VCF Peak to the right as you keep playing notes. The wah sound becomes even more pronounced without the filter self-oscillating to the point where it becomes a high pitched squeal. I think this is because the Cutoff Int is higher so the roll off on the Cutoff frequency is sharper, reducing the higher end harmonics - in my opinion, thoughts, etc.

Click the link below to hear what the Keys might sound like now:

Turn VCF Peak slowly to the right, hear a more pronounced wah

Step 11: Record a simple melody on the sequencer. Run it and now turn up the Decay/Release and listen to how it changes. Definitely some interesting changes. Use motion sequencing if you want to experiment and have some fun. Hint: Try smaller changes.

Try larger changes as well. Experiment with it.

Click on the link below to hear an example of how the Keys can sound:
Changing Decay/Release from 12 o'clock to hard right and back

Step 12: Make sure motion sequencing is off at this point. Slowly increase Sustain and listen to the notes get longer in duration and fuller in sound. Try using the LFO Rate and Sustain for sounds approaching distortion in quality of timbre.

Click the link below to hear what the Keys can sound like now:
Keys with changing the Sustain

Listening to Other People's Music
Listening to other people's music and choosing your sound as your goal can be a great place to start designing sounds. This tutorial has given me new appreciation for the practice of covering other people's music. Before, I was mainly working on my own sounds from scratch but not really having a predetermined sound in mind. When you are starting out this way is exciting for awhile but you can get stuck in designing similar sounds.

In my opinion, the ability to make great sounds will be gained from experience over time and effort. Use the tools you have - recordings that are available in so many ways these days. I am sure I will start from scratch along the way with nobody else's sound in mind but, I am also learning how to design those new sounds from developing from the sounds I hear.


There are a wide range of sounds to be had using the controls in this tutorial. Both the knobs and the keyboard settings can be changed for different effects. Also consider the Voice control and if you are using the Keys by itself, change the Octave knob to get different ranges of sounds according to pitch.

Years ago, I went to a weekend workshop and brought my Yamaha F310, their entry level acoustic guitar at that time. I even wrote a song while there about all the people taking part. There was a guy there with his partner whom said he played semi-profressionally. I wondered if he could really make my guitar sound better or if that was something people just said.

He made that guitar sounds incredible. It sang. The quality of the timbre was not great but the music came across and was appreciated by all those whom listened. One more testatment to the saying that "it is not the instrument but the person playing it that makes it sound great."

Share the knowledge!

Wednesday, 10 April 2019

VCV Rack Tutorial 1 – VCO, VCA, Sequencer and Oscilloscope Modules

VCV Rack Tutorial 1 – VCO, VCA, Sequencer and Oscilloscope Modules

This tutorial is meant for the beginner to VCV Rack as well as synthesis. It is not written by an expert but it does provide a fair amount of detail. The first section just provides the briefest description of the modules to use and the connections made. If you want more details, read the rest of the tutorial. Please comment below.

The plan is to make more tutorials to make more complicated patches that resemble both mono-keyboard type synths as well as just experimentation. Modular synths excel at experimentation. Look for application of filters, envelopes and MIDI modules as well as Bridge to route the audio to your DAW. Who knows where it will go from there.

Short list:
>1) Download VCV Rack at
Install VCV Rack.
>2) Login to VCV Rack in the program.
    Click “Manage plugins.”
>3) There is more than one way to do something. Experiment as needed.
>4) Place the AUDIO module in the rack.
    Select the proper settings in the AUDIO module for your computer.
>5) Add VCO-1 module from the Fundamental section.
    Place a patch cable from VCO-1 “SIN” output to AUDIO “INPUTS 1.”
    Adjust the VCO-1 “FREQ” control to get sound.
>6) Making noise more interesting
    Add a VCA-2 module from Fundamentals.
    Place a jumper cable from VCO-1 “SIN” output to VCA-2 “IN” and from “VCA-2 “OUT” to AUDIO “INPUTS 1.”
    Adjust the VCA-2 “LEVEL” to the maximum. Adjust VCO-1 “FREQ” until you hear sound.
    Adjust both of the above controls to see what works.

    Add the SEQ-3 module from Fundamentals.
    Place a patch cable from “ROW 1” of the SEQ-3 module to VCO-1’s “V/OCT” input.
    Place a patch cable from any of the VCO-1 outputs (“SIN,” “TRI,” “SAW,” or “SQR”) to VCA-2 “IN.”
    Place a patch cable from VCA-2 “OUT” to “INPUTS 1” for mono left or “INPUTS 2” for mono right or “INPUTS 5” for mono both sides.
    Adjust SEQ-3’s “ROW 1” controls to different levels. The green LED’s above the SEQ-3 “GATE OUT” can be selected and deselected to provide different notes to play or not play.
    Refer to the details of section 6) for more details on patching cables for more interesting sounds.
>7) Adding the SCOPE
    Add the SCOPE module from the Fundamentals section.
    Place patch cables from any output modules to the SCOPE “XIN” or “YIN” or both to see what those waveforms are doing.
    To start with, take the VCA-2 “OUT” to SCOPE “XIN” and watch the waveforms made as the sequence runs. Change the SCOPE “TIME” control for different details.
    With the “TIME” control all the way to the left, you get the big picture of what is going on.
    With “TIME” all the way to the right, you might not be seeing what you need to see at all. Turn “TIME” all the way left and slowly increase it in stages until you see waveforms that resemble the examples given below.
    Note that you can use SEQ-3 “GATE” outputs of any kind to see what happens when those signals are applied.

There you have it, the short and below, the long of it. Have fun!

Detailed Section of the post:

>1) The VCV Rack website is:

Download VCV Rack – one of the OS options: Windows, MacOS, or Linux.
    Linux is actually the easiest to install so if you have a Linux OS, you are in luck. There are less steps for a Linux install than the other OSs, less clicks and/or less command line instructions. MacOS and Windows are actually very easy to install as well as both of those operating systems' versions are automated. It is simply a double click and follow the instructions.
    The Linux install is a simply download, unzip the file in whatever directory you like and it makes its own directory called Rack. Change directories and run VCV Rack. With Linux, you can double click the executable or you can navigate to the directory where it was installed and use the command:
$ ./Rack

>2) VCV Rack with no modules installed, not logged in:
At this point, you should login. You can login in the program itself.

The icons at the top of the window are typical of any program in that you have a "New" icon, an "Open" icon, a "Save" icon, etc. Here is the list with shortcut keys where they are provided:

New Patch  -- Ctrl-N
Open Patch  -- Ctrl-O
Save Patch  -- Ctrl-S
Save Patch As  -- Ctrl-Shift-S
Revert Patch  -- no shortcut key
Disconnect cables  -- no shortcut key
Engine sample rate  -- no shortcut key  -- click on the button and there are options:
    Pause engine
    44100 Hz
    48000 Hz
    88200 Hz
    96000 Hz
    176400 Hz
    192000 Hz

    The “Pause engine” option is good if you want to stop the sounds produced temporarily.

Toggle power meter (see manual for explanation)
Cable opacity  -- click and slide to change
Cable tension  -- click and slide to change
Zoom  -- click and slide to change
Manage plugins  -- click to go to the VCV Rack plugins webpage
Updage plugins  -- click to enact the plugins options selected on the plugins webpage

One of the first things you should do is click “Manage plugins” in the VCV Rack program, located at the top of program. This will bring you the webpage where you can select a number of different plugins, some free and some paid. Download and install occurs when you click the “Update plugins” button in the program.

You will have to create a new account if you have not made one already. If you have, you can login to allow your plugins to be selected if you have not already logged in within the program.

You can select which ones you want to download by selecting the option on the right of the information for each plugin. One of the great things about VCV Rack is that many of the modules for download are based on hardware modules, made by the same companies.

If the plugin is free, you can go back the VCV Rack program and click “Update plugins” to load the plugins into the program.

>3) There is more than one way to do just about anything. Adding modules according to your own ideas of how to set things up is your own preference and will differ from person to person. What is attempted to do here is demonstrate some simple concepts given a noob’s perspective to modular synthesis. The great thing is that if you mess things up, you can easily start again.

As with a DAW, you might want to set up a template situation to make things easier for a basic situation for using VCV Rack. You can save the patch at any point and it is possible to save patches in a directory different that the one that VCV Rack defaults to when you first go to save your patches.

>4) Setting things up:

In order to hear any signal, the Audio module needs to be in place. It is good to have a type of workflow in the way you place your modules. Left to right is a common way to work. In this way of working, the Audio module will be placed on the right. It is the last module between your modules and the speakers or headphones.

Audio is found under the Core group of modules. On a Mac, instead of a right click, double finger click to access the shortcut menus. Right click anywhere within the rack space to access the shortcut menu to select modules.

When you place the Audio module, you should select the proper settings for your computer. There is there are four sections available to change according to your system: i) Audio driver, ii) Audio device, iii) Sample rate, and iv) Block size.

i) Linux Audio driver tends to be ALSA but there are the JACK and Bridge selections as well. JACK is another audio interface system for Linux and Bridge is used to bridge the audio produced by VCV Rack to a DAW. Bridge is an option for all three OS’s. Windows commonly uses ASIO4all but choose whatever your drivers are for Windows. OSX, for Macs, is CoreAudio.

ii) The Audio device you choose can vary and sometimes there is more than one option that will work. If you are using a USB audio interface between your computer and the speakers, you will want to select that option. You can use VCV Rack without a USB audio interface and there are a number of options for Linux. Selecting some options in Linux can often result in YouTube tutorials not playing while you have VCV Rack running. Selecting other options can often allow you to watch those tutorials. Experiment to see how things operate. Different selections can change the way the audio gets routed to the speakers or headphones.

Another warning is that in the past, selecting JACK as the audio driver has resulted in any videos in a webbrowser not playing at all when a program using audio is running. If you learn more about JACK, you might be able to change that.

iii) Sample rate can vary a lot and you generally want to choose the highest rate you can for your computer. For older computers, 44100 Hz is the best choice as it puts the least amount of processing strain on your computer and you can add more modules to get it to run interesting patches. The higher the sample rate, the more your CPU is used doing calculations to output the audio. This is something you can change partway through making your patch so do not worry about picking a permanent setting if you need to free up some processing power. 44100 Hz is CD quality so that is quite good for most purposes. Many newer computers will have no problems running 192000 Hz.

iv) Block size is important. The lower the block size, the faster the program reacts to changes. If you use a MIDI keyboard to play notes then you want low latency provided by a smaller block size. One problem that can occur with smaller block sizes is noise in the audio produced by the program. I cannot explain as I do not have the knowledge about why it does that. However, this is a common problem with all audio programs that have block sizes as parameters that can be changed. A higher block size results the audio being produced to be of better quality with the tradeoff of more latency. Higher latency times become more apparent when you do use something like a MIDI keyboard to play notes in VCV Rack or a DAW.

As the ear cannot often detect small differences in audio, choose the smallest block size you can without getting noise or crackling in the signal AND an acceptable latency. If you use VCV Rack in a way that latency does not come into effect, choose a larger block size. Sequencing and just recording VCV Rack could be one such example. However, beware of things like turning knobs on the modules that those changes might introduce latency effects that are noticeable. Latency times less than 10ms are often not very noticeable by most people.

5) Making noise

Now that you have your Audio module in place, it is time to make some sounds. You need to add a VCO (voltage controlled oscillator). To start, you might as well stick with Fundamental.

Right click on any space in the rack and select the Fundamental section. Within that you will find many modules, but the one you want is right at the top, VCO-1. Click that and put it on the left side of the rack. In the picture below, you can see the modules menu from right clicking as well as the VCO-1 module already placed on the rack.

So here is a quirk with a very easy work-around. When I placed the AUDIO module, I selected the Audio device as the “hw:HDA Intel, 1-2 out)” option. This allowed me to hear the sound produced by VCO-1 when I placed the patch cable from “Sin” on VCO-1 to “Input 1” on Audio. However, if I go to play a tutorial on YouTube, the video will not start. The screen does the circle looping thing over and over. When I select “default (1-8 in, 1-8 out)”, the sound is audible on VCV Rack and the YouTube video plays. No patch cables means still no sound but I get to that after the next paragraph.

If you run into a situation like this, look at the available options to see what can be changed. I suspect that it is the more ins and outs from “default (1-8 in, 1-8 out)” that allows audio and video to play from the webbrowser and VCV Rack at the same time. I have not experienced the same thing on Windows or on a Mac. Things just play. So Linux has some advantages and you can do lots of stuff on Linux that you cannot do on the other OS’s but sometimes Linux requires more adjustments to get things to work. All-in-all, I like using Linux because of these quirks, their fixes and the ability to do many things on your own and personal customization that cannot be done the same way on other operating systems. There are times with certain hardware audio device selections where I do not have to connect the AUDIO module inputs to the outputs and hear sound but, to be thorough, you should connect those inputs to outputs.

Placing patch cables:
In the diagram shown here, you see three inputs and one output. The INPUTS are the black circles in the centre with two grey rings around the black circles. The OUTPUTS are the black circles with two grey rings around the black circles which are then surrounded by a black rectangle. The three INPUTS here are labelled “EXP,” “LIN” and “IN.” The OUTPUT is labelled “OUT.”

Connecting inputs and outputs of modules is simple. Click on the output of one a section of the module and while keeping the mouse button down, drag the cursor to the input where you want the cable to go. When people use modular synths, they tend to colour code their connections. You can do this in VCV Rack as well. Admittedly, I have not used this feature yet, but it is easy to do. If you want a particular colour cable and it is not the first one that shows up, let the mouse button go and click, hold the button and drag again and see what colour you get. There are only four colours so it will not take long to get the correct colour. The colours are red, blue, green, and yellow.

Running multiple cables:
If you want to run more than one cable from an output to an input, press the Ctrl key before clicking on the output jack. You cannot run multiple cables to one input. Take note that there are modules that allow for multiple inputs to be mixed to one output.

If you want to get rid of one cable, click on one of the cable ends, hold the mouse button down and drag it off the connection. It will disappear. There is a button in the top menu bar, 4th from the right, that looks like a cat. That button will remove all the patch cables from your modules. I suspect that the creators of VCV Rack have had some problems with cats chewing their cables.

After all that, now that you have had a minute or two to listen to that Sin wave or Triangle, Saw or Square, you are probably thinking this is a pretty boring sound. Before you turn down the volume or disconnect the patch cables, there is an option to “Pause engine” which turns off the signal chain so you will hear no sound. This can be handy when you start to hear unwanted sounds and need to make changes without hearing the immediate direct results. You could remove patch cables at certain specific points. Once you start to build large patches, the “Pause engine” option is likely the easier one. The icon to click to get to “Pause engine” is to the right of the cable chewing cat and is called “Engine sample rate.” It looks like a triangle wave, third icon from the right in the picture above. Click the icon then select “Pause engine.”

Now, the thing to remember here is that before you can hear sounds again, you need to go back to “Engine sample rate” and select the toggle counterpart to “Pause engine,” which is “Resume engine.” Using “Pause engine” will undoubtedly result in forgetting to select “Resume engine” to get sound again. Prepare for a little frustration until it sinks in. It would be handy for the development team to make the option toggled with a shortcut key.

>6) Making noise more interesting:
Adding a VCA and then a sequencer.

First, add a voltage controlled amplifier to allow for the volume of the sound to be controlled. Doing so at this point might be a little more relatable. The volume of the sound can be controlled by turned the “Level” knob on the module. The “Level” knob is indicated by the arrow in the picture below. The other controls on the module are inputs and outputs – the “EXP” jack, “LIN” jack, “IN” jack, and “OUT” jack. The VCA-2 module has a second section underneath it, which is identical to the top section.

Right click on an empty space on the rack and select “Fundamental > VCA-2” and place it beside the VCO-1 module. Again, INPUTS and OUTPUTS on modules are shown as circles around black holes. They are meant to look like jacks for 1/4” instrument cables that are commonly used for electric guitars and other musical instruments that have electrical signal outputs. OUTPUTS on modules are indicated by  surrounded by a black rectangle while INPUTS are simply shown as circles around the black circles. On the VCO-1 module, click on the “SIN” output and hold the mouse button down and drag the other end of the cable to the IN input on the top VCA-2 module. Click and hold the mouse button, dragging from the same section of the VCA-2 module’s OUT jack to the 1 INPUT on the Audio module. Click on and hold the mouse button from the 2 INPUT on the Audio module to the 1 OUTPUT of the same module.

Clicking on a control knob and dragging it up will turn the control up and dragging it down will turn the control down. Click and turn the Level control up and you should hear the volume of the signal get louder. Turn the Level control down and the volume of the signal will decrease.

Turn the Freq control up on the VCO-1 module up and you will hear the frequency output increase in pitch. Turn the Freq control down and the pitch will decrease. At this point I like to use the VCA-2 Level control to lower the output signal before I start changing things. However, if you scroll down in the program window, you will see that it goes on and on for just about as long as you scroll down. The same is true for scrolling the window to the right. This means you can have a lot of modules in your patch and at some point it will become easier to stop sounds by selecting the “Pause engine” and Resume engine” to stop and restart the output sounds.

Adding the sequencer:
Sounds at this point are still pretty tame but they are getting better. For more musical results, I like to add the sequencer at this point. Just remember that there are many ways to do things. If you have an idea about something, go ahead and try it and see what happens. If you do, it is still a good idea to save your patch and start using different names to indicate the stage you are at.

Right-click on VCV Rack, and select “Fundamental > SEQ-3,” placing it beside VCA-2. There is a section of outputs on the SEQ-3 module labeled “GATE,” “ROW 1,” “ROW 2,” “ROW 3.” From now on, when the phrase click on “input / output” and drag to “input / output,” it should be assumed that you are holding the mouse button when you click to drag the cable to its destination.

Using the sequencer to make a sound pattern, or just commonly referred to as a sequence:
Click on “Row 1” and drag the cable to the VCO-1 module’s  “V/OCT” input.
Click on one of the VCO-1 outputs, “SIN,” “TRI,”, “SAW,” or “SQR” and drag the cable to VCA-2 “IN” input.
Click on the VCA-2 “OUT” and drag the cable to the Audio module’s “INPUTS 1.”
Now you can make sure the VCA-2 module’s “Level” is turned up so you can hear sounds. On the SEQ-3 module there are three rows on controls. Vary the controls in that row to get different pitches. There is another general pitch control which adjusts the overall pitch of the sequence. That control is on the VCO-1 module – the “FREQ” control. Varying that control moves the overall pitch up and down.
>7) Adding the Scope:
At this point, before getting into more control, it can be very useful to use the SCOPE module. Scope is short for oscilloscope. Do not worry, the SCOPE module is a lot easier to use than a regular scope. It is simply a matter of taking an output and connecting it the “XIN” or “YIN” on the SCOPE. XIN and YIN in this case are two channels on the scope. This means you can look at two different signals at the same time which can be useful in understanding what one control does to the signal after it passes through the module. It can also be used to monitor things like “GATE” signals or basically, any other output there is on VCV Rack.

Here is the last patch I made for this tutorial. It builds on the rest of the tutorial and I just placed some patch cables to experiment. Note the arrows are pointing to two outputs. Those are also patched to the SCOPE module. The blue signal on the SCOPE is the XIN and the pink signal is YIN. The most common control to change on the module is “TIME.”

If your signals are too close together where it all looks like one thick line with variations on the top and bottom, you need to adjust the “TIME” by increasing it so you can see higher period.

Out of all of this, this is where a little math can come in handy. Frequency and the period of a waveform are related.

T = 1 / f

where T is the period in seconds and f is the frequency in Hertz.

So, what are the period and the frequency? Have a look at the following example:

This is a rather poor representative of a sine wave. However, it does demonstrate some good points.

A complete cycle of a waveform has two zero crossing points after its beginning zero crossing point. There are two peaks at amplitude +A and -A and each of those happens every cycle. This is fundamental knowledge in looking at a waveform. It allows you to identify a waveform and recognize where each cycle starts and stops and to determine what values it has for its properties. Doing so allows you figure out when you are looking at a waveform that differs from another waveform.

In addition to the peaks and crossing points, it is important to know what the scales are that are being used on the X-axis and Y-axis. With a waveform and oscilloscopes, the time value is on the X-axis and is expressed in some value of seconds. Time values that are typical in audio work run anywhere from 10 seconds to 5 hundred thousandths of a second (0.000 05s) which represent things from the period of a very slow LFO to what is considered to be the upper range of human hearing. What does that mean in frequencies?

That is where the equation the expresses the relationship between time, T and frequency, f comes into play.

T = 1/f,
where T = 10s
f = 1/T = 1/10s = 0.1 Hz

To provide the value T for the upper limit of human hearing, I actually used the more commonly used frequency to provide T instead of using T to provide the frequency. This shows that the equation is often used to convert one to the other.

Where f = 20,000Hz, or more commonly 20kHz,
T = 0.000 05s
That value of T would be more commonly expressed as a value of microseconds.
T = 50 µs.

To make it simpler to type, the micro symbol, is often expressed using a regular u. However, if it is written by hand, it is good practice to use the actual symbol, µ. So, you might see this

50µs = 50us.

This stuff becomes important when you look at a scope. The amplitude of the scale will often be expressed in some value of Volts, ranging from uV (microVolts) to tens of Volts (for audio work, or quite higher if working with tube technology). The time scale will often be expressed in values from the us (microseconds) up to full seconds. Milliseconds are often seen on the time scale on a hardware oscilloscope but using the time control knob on the SCOPE module will not show those values but they pass through those ranges nonetheless.

The point of all this discussion is to give you some knowledge to use to understand what it is you are looking at on the SCOPE. The “TIME” control can vary from time values, the period of a wavelength from the very small, in the 50us range, all the way to the left, to the lower range of hearing, approximately 20Hz.

f = 1/T
f = 20Hz
T = 1/f = 1/20Hz = 0.050s = 50ms (50 milliseconds)

I am estimating the limit of the SCOPE modules “TIME” control using the lower limit of human hearing. However, you can do your own qualitative test using your own hearing and do a rough mental extrapolation.

Put the following modules on the patch: VCO-1, VCA-2 and SCOPE. Run a patch cable from VCO-1 “SIN” out to VCA-2 “IN” and a patch cable from VCA-2 “OUT” to SCOPE “XIN.” Disconnect any cables from the previous patch to AUDIO module “INPUTS” and run a patch cable from VCA-2 “OUT” to AUDIO “INPUTS 1.” Now, turn up the VCA-2 “LEVEL” all the way. Then slowly turn up VCO-1 “FREQ” until you hear a low bass sound. That will be around 20Hz give or take 10-20Hz. At that point, each square on the SCOPE module on the horizontal axis will be about 50ms. You can use the equation to check it as I did above. When you begin to hear the low bass sound, the waveforms will be occurring more frequently on the SCOPE screen. Now decrease the “FREQ” control on VCO-1 again. I estimate at the low end, that T for that waveform to be in the 4s to 10s range.

Here is what the test patch looks like:

In this screenshot, the Audio module is on the right side of the screen. The good thing about VCV Rack is you can place modules off to the right or down below where you cannot see them onscreen. As long as the patch cables are used, it will all work. To test a patch, To demonstrate one use of the SCOPE module, I placed a few modules off to the right side and disconnected to other patch cables connected to the AUDIO module.

While SCOPE does not give values for the TIME scale on the screen, it does give voltage values.

If you have a real oscilloscope you can the time scale values for yourself. Maybe someday I will.

Here is a screenshot of a patch I made. See if you can construct it and have a listen!