What do you feel is inside a KERNOM RIDGE ?

[Vivek]

Kernom ridge talks about morphing of clipping characteristics



How do you think they did it ?

I guess 4 Digipots, to control rubber diodes and compliance resistors, all controlled by a microprocessor



And what is your best guess about the pre and post tone controls and the mid control ?

[puretube]

Look here - first guesses:
https://www.diystompboxes.com/smfforum/index.php?topic=129656.0

[Rob Strand]

To me it looks like there are multiple functions.

- Soft Clipping:
   Programmable "rubber diodes"  by using a divider in the feedback path would work, one for each polarity.
   However, it could be more than that like diode series resistance.
   Fixed forward gain but perhaps gain in the feedback path to make the soft clipping harder.

- The hard clipping looks separate to the soft clipping and the soft clipping is present even when there
   is hard clipping.

- For medium hard clipping it looks like the gain is cranked while the clip levels are fixed; since the slope at
  the zero crossing changes.

- For hard hard clipping the gain increases more but the hard clip level is decreased.

There's so many way to implement.   Who's to know if the circuit has fixed hard clip level, like an opamp clipping
and both pre and post gain is varied.

[EBK]

Raise your hand if you'd prefer to build multiple pedals than have one that did this. 
I view this as an overthought design.

[ElectricDruid]

Raise your hand if you'd prefer to build multiple pedals than have one that did this. 
I view this as an overthought design.

Multiple pedals is more flexible too, because you can stack them. That pedal might eb able to do the sounds of four or five other pedals, but it can only do one at once.

I think what it *does* demonstrate quite nicely is the way that once you get digital control deep into a circuit, you can come up with *entirely new* front panel controls that can change multiple parameters at once under the hood. That can give you a simple interface and a lot of power.

Another example is the "Vintage" knob on the recent Prophet 5 Rev.4. It lets you select the sound of different revisions of the instrument by subtly (or not so subtly) changing tuning and timings across *many* parameters of the synth (for example variation between envelopes, and detuning and instability in the oscillators).

This kind of thing is entirely different to the standard analogue front panel control which is varying the value of one component in a circuit. It could be done with analog, but it'd get complicated and unwieldy fast.

[Rob Strand]

I think what it *does* demonstrate quite nicely is the way that once you get digital control deep into a circuit, you can come up with *entirely new* front panel controls that can change multiple parameters at once under the hood. That can give you a simple interface and a lot of power.

There's plenty of digital pedals which use pots instead switches to switch modes (perhaps 10 to 15 years ago).  A pot is cheaper than a multi-position switch however changing models in the analog domain will require some solid state switches.

In a sense the Mood control on the Kernom interpolates between modes.  The transitions *between* modes are smooth,  it's hard to perceive or label it as a  "mode" change.

[Vivek]

I feel KERNOM RIDGE is 4 digipots

1. Positive swing rubber diode clipping adjustment
2. Negative swing runner diode clipping adjustment
3. Positive swing compliance
4. Negative swing compliance

And a bit of smart code which adjusts these 4 digipots. I feel that the waveforms shown in the clipping gif would be easy to achieve with such configuration.


Maybe the basic rubber diode based clipper could be something similar to :



Or

https://www.elektormagazine.com/magazine/elektor-198599/46980



So the question is

If adjustments of clipping level and compliance are so powerful, and we don't want to get into digital control, and we don't mind playing with 4 knobs, is it worthwhile to build an analog pedal with 4 knobs to control clipping. Can it really emulate all distortion pedals that came before it ?


PS it appears that KERNOM only claimed "infinitely variable" but it's the influencers who hinted it could match Bluesbreaker, Klon, King of Tone, Tube screamer etc

[EBK]

is it worthwhile to build an analog pedal with 4 knobs to control clipping. Can it really emulate all distortion pedals that came before it ?

The problem is one of use case.  Consider how you would be using such a pedal.  If it is on a pedal board for live performance, it would likely stay in a single useful configuration, ready to go.  If you are in a studio situation, then you have access to digital post-processing to dial in the sound you want through software.

The niche that is left is largely home noodling and garage bands (I use the term lovingly here--minimal setup bands is what I really mean, if that makes sense). I would suggest the home noodling is the best fit.  You can dial in what suits your mood, as the control label of the original suggests.

Is it worthwhile to have one pedal with four knobs that do this?  Depends on how you evaluate your fun.  I'd say it is worthwhile to design such a thing and play around with it, but it would just be a toy.  I, however, don't mind pedals that are merely toys. 

As I have suggested previously, though, I like to build lots of toys and allow them all to have a narrower purpose.  Your mileage may vary. 

You would, of course, get tons of admiration from all of us here if you designed and built such a creation, especially if you shared knowledge or made boards available.  So, there's that too. 

As a commercial, non-DIY product, I'd pass.  Otherwise, I love it.

[ElectricDruid]

If adjustments of clipping level and compliance are so powerful, and we don't want to get into digital control, and we don't mind playing with 4 knobs, is it worthwhile to build an analog pedal with 4 knobs to control clipping. Can it really emulate all distortion pedals that came before it ?

For me personally, no, I don't think it is. The whole point of the Kernom pedal is that it controls all those parameters seamlessly without you having to think about it. As soon as you go and put tons of knobs back on it, the whole point is lost (in my view).

Imagine we built a digital programmable pedal with a 21-band EQ ahead of a clipping stage, and a 21-band EQ afterwards. We could program all sorts of interesting digital knobs to give us responses that went from "blues" to "metal" or from "Dark break-up" to "heavy crunch" or whatever we could dream up. But if we just made the entire interface of 42 EQ controls and a drive knob and volume available to the user, that's kind of missing the point. Of course they'd be able to do anything we could do with our software, but the whole point is to reduce a lot of technical tweaking to a few musical controls that people can use to get the sounds they want.

So many of the best instruments have managed to do this in some form or another. Many people have said that you can't get a bad sound out of the Roland SH-101. The parameter ranges are set up so that pretty much everything you do is useable somehow. The Juno-106 is another Roland instrument in a similar vein - very pared down interface, but still popular today because they're easy to get a great sound out of.
On the flip-side you've got stuff like the Yamaha DX-7 that changed the sound of pop music with its sounds, but which was so awkward to program and to get the sound you wanted that a whole industry of secondary sound programmers grew up around it.

I've worked on a lot of digital-brained products, and the interface is *critical* in not making them *feel* like they're a digital gizmo. If you do it right, it feels like a bit of analogue technology, where you tweak the knobs and something happens. If you get it wrong, it's a confusing mess of mode changing and parameter knobs that swap functions depending where you are and etc etc - Gagh! Nightmare! No thanks!

[FiveseveN]

But if we just made the entire interface of 42 EQ controls and a drive knob and volume available to the user, that's kind of missing the point.

I feel attacked
One thing has been bugging me about this discussion though: why is everybody assuming that the animation is an accurate representation of what the box does?

[PRR]

..... why is everybody assuming that the animation is an accurate representation of what the box does?

Because it is such a great animation! How can anything so intuitive and cute be wrong in any way?

It IS the several likely forms of distortion. Whether the smooth transitions are accurate or fabricated falls under suspension of disbelief.

[Mark Hammer]

So many ideas about effects seem to be predicated on a signal generator of pure waveform and steady state, which bears little resemblance to what a guitar provides.

Speculating about design, based on an animation like that is not going to end up anywhere accurate.

Having said that, look up the 'variable fuzz box' that was in several different language versions of Elektor, 40 years back.

[Vivek]

Having said that, look up the 'variable fuzz box' that was in several different language versions of Elektor, 40 years back.

I had made that when I was in University!

And I linked to it here

https://www.elektormagazine.com/magazine/elektor-198599/46980

[FiveseveN]

Regarding my previous post, here's a demo that includes some real life scope traces at about 1:50. All ~7 seconds of it but hey, it's better than nothing and not very close to the animation by my eye, but that's going to depend on the gain setting.