Kore, Komplete, Reaktor @ cdm

Minisite with tutorials, tips, features on making the most of Native Instruments music production tools

Feedback, as viewed on an oscilloscope. Photo (CC) Audin, via Flickr.

Ed.: Feedback loops usually fall into the “things to avoid” category, but cleverly used, they can be a powerful creative technique. Part of what Kore is about is being able to create unusual routings easily, so where better to start than a loop? Eoin walks us through sound design with feedback here, using an external input (like a mic) or plug-in as a source, or even self-oscillating (crank up the gain, and the setup itself will produce its own sound). -PK

If you’ve read the Kore 2 manual, you might have seen mention of the possibility of feedback loops, but there are no instructions for how to safely set this up. Today we’re going to do this step by step, and hopefully by the end you’ll have an idea of how easy this is and the kind of wild sounds you can get.

If you don’t have access to Kore, you can still hear the end results; the audio examples below demonstrate some of the sounds that can be obtained with just a few simple routings.

You can use the Kore demo to complete tutorials; sessions shut down every 30 minutes, and saving is disabled, but there are no other limitations. The examples included work with Kore 2′s internal engines and effects.

Before We Begin

While you definitely don’t need a hardware Kore controller to do any of this, it will make adjusting assigned values much easier. We’ve included instructions on which knobs to assign and when. Before we begin, you should know that creating signal routings of this type can seriously damage your ears and speakers. Monitor at low volumes and put a limiter on your Master channel (there is one in Kore’s included effects). Now, let’s use feedback as a force for good!


1. Create the sound. Open up Kore and create a Source channel if there’s not an empty one already. Right-click in a sound slot here and click New Sound. This will be our ‘container’ for the entire feedback loop, which we can then save as a .ksd (KoreSound file).

2. Add a Limiter. Put a Limiter device on the container sound’s Master channel (you’ll find this in Kore’s Internal Effects menu). Leave the controls at 12:00 and decrease the Out Gain to -3dB.

3. Make a “kill” knob and button. Assign your top left-hand knob to the Sound’s Master Volume control (to the far right of the controller area) — this gives you quick access to the master level. Assign a button to bypass the sound altogether by first clicking on Learn and then on either the sound’s channel number or the little circle icon next to the sound’s name. Between these and the Limiter, you’ve got plenty of ‘insurance’ in case you need to lower the volume in a hurry.

Create an Input Channel

It’s good fun to drive the feedback chain with your voice – this is the way we’ll set up the sound – but feel free to use another source.
01 Mono To Stereo

Mic input: If you’re using a mic, right-click a sound slot in your container sound and select New Sound. Create an Input channel and assign a knob to the Input Gain control (and a button to mute the incoming sound if you like). Using the Input Source selector, route an audio signal into this channel. Place a Mic Conditioner device on the Input channel and turn on the MS to LR button (pictured). This will convert mono mic signals to stereo. You can also filter low frequencies with the Mic Conditioner and introduce a little delay on either channel to thicken up the sound.

Plug-in input: If you want to use a plug-in as a sound source, right-click a sound slot in your container sound and select New Sound. Create a Source channel, name it ‘Input’ and simply insert whichever plug-in you want to use.

Create Feedback Channels

A Rotor for effect: Next, create a Group Channel beside your input channel, put a Rotor device in it and call it ‘Rotor’ for clarity. You don’t necessarily have to have any effects here, but this one allows you to vary the dynamics in interesting ways and add some grit. Lower the Input gain on this channel to about -4dB, and assign a knob to the Output level. As we’ll want a more subtle control over the feedback amount, we’re going to limit the Output level to between -13dB and -8dB. To do this, click on the Assign Tab for your Rotor Output level knob and limit the Min and Max values for the assignment to 47 and 56, respectively. Call this knob ‘Feedback’ [Fbk].
In the Rotor device adjust the settings as shown in the screenshot and assign a knob to the Fast knob. Feel free to assign other controls you think might be fun to play around with – High Cut, Low Cut and the Fast button are all good contenders.

02 Rotor Settings

Delay the loop: Next create a Group Bus, call it Delay and put in another Mic Conditioner device. Add some delay time. Somewhere between 100 and 200ms on both channels is fine; it’s not an exact science & doesn’t matter if the two channels are different. This ‘buffer’ will prevent our feedback loop from getting out of control too quickly. Again, you can assign macro knobs to parameters here, but remember, the lower the delay setting, the easier it will be to send your feedback loop straight into overdrive.

This Rotary Speaker channel and Delay channel together will be our feedback loop. Let’s connect them and see what it sounds like.

Make your routings

Change the output routing of your Input channel from Master to Rotor. On your Rotor Channel, change the Output routing from Master to Delay (your Output Level assignment will stay in place with its limits intact).

Complete the feedback loop

Now on the Delay channel, assign your first aux send to Rotor. Make some noise in the mic (or your sound source) and you should be able to set the sound feeding back onto itself. If not, check your input gain and the feedback amount. A cool trick to try is to just let the sound self-oscillate. Simply turn the feedback knob up full and wait a while… even with no sound source you can get a working feedback loop in this way.

03 Routing Diagram

You’ll notice it can be tricky to keep the signal feeding back at the same level. It takes a bit of a balancing act to get it right, but you should be able to get a stable loop to work with. If the level meters within the Rotor/Delay channels are fully in the red, don’t worry about it – this digital distortion provides a tasty crunch that’s high in fibre ;)

Once the sound is feeding back and not rising or falling in volume, its timbre pretty much stays the same. This is where the fun starts – by making tiny variations in seemingly unimportant FX parameters, you can completely alter the sound of the loop. If you hit on the right combination, the sound can start to take on a life of its own… try minutely altering the Delay settings or adjusting the Mix control on the Rotor device.

Adding Effects

After this, you can basically add effects to taste. As an example, I’ve created a KoreSound that contains a feedback loop and some of Kore 2′s Internal Effects. In this case, the feedback loop doesn’t go directly to the Master, but passes through the effects first. I’ve recorded some example MP3s of improvisations with the .ksd to give you a feel for what can be achieved if you want to delve further.

Ed.: You might want to turn down your volume to avoid upsetting neighbors / cats / small children — Doctor Who fans, enjoy!

KoreSound .ksd file


Audio examples







Download the whole set of MP3 audio examples (zip)

You can insert other effects to either channel directly within the feedback loop if you like (watch your levels), but the more devices you add to the chain, the more difficult it’ll be to diagnose problems if it’s not behaving the way you expect. It might be a good idea to have each plug-in change the sound in only one way, such as just impacting dynamics or just changing the pitch, so that you can better predict what will happen if you disable it.

When you’re finished following through the article, don’t forget to come back and show us your own variations on this theme!

16 Responses

  1. [...] How to Route Feedback Loops in Kore – On Purpose [Kore @CDM] [...]

  2. scott flavin

    Augh…why is fun always so expensive?!

  3. Peter Kirn

    Well, *fun* can be free … tools do sometimes require money. But we’re working on getting some freebies out there, as well, so stay tuned. The free Kore player doesn’t have the routing capabilities here, but it is free — http://www.native-instruments.com/index.php?id=koreplayer — and we’ll see what else we can do.

  4. Cyril

    Kore is great, but you have to pay to play with the routing capabilities.

    If you search a freebie, the best tool i know to explain and experiment with sound design is the Clavia Nord Modular G2 editor demo ! It’s a demo, but not as limited as a classic demo can be. There’s enough module to make complexe sound design, and the save function is enabled. Last but not least, it’s standalone. You don’t need a G2 to use it. A real gift.

  5. grimley

    I’ve had Kore 2 for a while but I’m still a total newbie when it comes to anything other than loading the presets. I got lost on step 3: Assign your top left-hand knob to the Sound’s Master Volume control — this gives you quick access to the master level. Assign a button to bypass the sound altogether by first clicking on Learn and then on either the sound’s channel number or the little circle

    err … what “Sound”. Which master volume control. What sound channel number and where is this little circle?

    Ok .. so I’m an idiot and I really appreciate you guys doing this – it’s brilliant stuff… but video tutorials would be excellent for this kind of thing.

  6. Eoin Rossney

    Hey Grimley, I can see how that could be confusing. Step one should probably read:

    Open up Kore and create a Source channel if there’s not an empty one already. Right-click in a sound slot here and click New Sound. This will be our ‘container’ for the entire feedback loop, which we can then save as a .ksd (KoreSound file).

    I probably didn’t emphasise enough that we’re creating an empty Koresound into which we put our feedback loop, so anything from ‘Create an Input Channel’ will be happening inside (i.e. on a sub-level of) this container Koresound.

    When we refer to our Master Volume control, this is the big volume knob you’ll see to the far right of the controller area when you left-click on the container Koresound, and the bypass button is simply the circle beside its name.

    The limiter is probably better off going inside the Koresound (i.e. on the master channel which is across horizontally from your feedback channels, not the top level master channel), so that it gets saved with the .ksd

    I hope that clears things up, if not shout back & don’t forget you can download the example .ksd and take a look at how things are mapped there for some more reference. We’re with you on the video thing, hopefully that’ll become more & more integrated as we go on.

    Cyril – thanks for the tip about the G2 editor, looking forward to checking out that one!

  7. grimley

    Eoin, thanks a million! I actually found the ksd after I posted and that has been very helpful. I’m beginning to see just how powerful this thing is. Heah – mind if I ask where in Ireland you are based? Originally from Armagh myself although residing in Seattle now.
    Cyril, I’m with you on the G2 … I’ve owned the kb version since it’s release and have found it much more accessible than Reaktor (although I wish it had non-volatile memory for sampling). The hardware integration though really makes the G2 shine (similar to Kore I guess in that respect).

  8. Eoin Rossney

    Excellent – I’ll see if I can change the instructions to make things a bit clearer. I’m based in Dublin – not as cool as Seattle or Peter’s NYC, but at least we have a massive upside-down sky city!!

  9. Peter Kirn

    I think Dublin is plenty cool. If we hold a belated launch party for this site, let’s do it there.

  10. Eoin Rossney

    I am totally on for that, not least because it’d save me a few quid on airfares :)

  11. Jarson

    Yay! I was able to make it past step 1, thanks to your comments Eoin. However, I am now stuck at step 2. I see the word “master” in 3 different places, but I do not know where/how to place an effect on any of them.
    Mind you, I’m not a complete idiot (I have no problem assigning effects and/or plug-ins to channels in my host program, Logic 8, for example), but I just do not understand how Kore puts everything together. I did read the Kore manual when I got Kore 1, and again when I got Kore 2, but It did not help me get beyond preset browsing. I would just cheat and load the .ksd, but would prefer to put it together myself with your walk-through so that I can really learn how Kore works.
    By the way, ALL of NI’s manuals leave me scratching my head (I have Komplete), so I am really looking forward to more tutorials for all of the other instruments, especially Reaktor.
    Thanks for your help Eoin, and Peter for this mini site!!

  12. Marc

    Hi, nice tutorial! It’s nice to have ressources like this, keep it up!!
    Only bugger, I think the audio.ksd link has gone… Can you check it?

  13. Eoin Rossney

    Hi Jarson, I’ve edited steps 1-3 slightly to make it a bit clearer which master channel we’re referring to, if you follow it to the letter it should work now. To put an effect on a master channel (the channel to the far right in any sound), just drag it to the sound slots (rectangles) on that channel, or right-click the sound slots to choose from Kore’s internal/vst menu.

    Marc, the link’s working for me so must be something on your end? Anyone else having issues with this?

    Oh & thanks for the compliments!

  14. kiruluda

    [quote]…click on the Assign Tab for your Rotor Output level knob and limit the Min and Max values for the assignment to 47 and 56…[/quote] Cool tutorial, but I was wondering if I had missed a step? I’m not allowed to change the assignment for plugin or channel pages. Should I have created a user page and then assigned a knob to the output level control? I wound up just skipping that part and completing the tutorial.

  15. [...] Tips: Controlling External MIDI Gear, Plug-ins Kore: The CPU-Saving Power of X in Live Performance How to Route Feedback Loops in Kore – On Purpose [...]

  16. Jessie

    low airfares…

    Our lives begin to end the day we become silent about things that matter. ~ Martin Luther King, Jr….

Leave a Reply