MeAmBobbo's High-Gain Tone Guide
Sculpt Your Distortion
The odds of you finding a profile that distorts just the way you want given your personal tastes, playing style, and guitar specs is extremely unlikely. But just because a profile was dialed-in in a way that doesn't quite work for you, doesn't mean you should scrap it yet.
Use some stomp effects before your stack block to sculpt the distortion tone you want. This can be EQ, a Booster, a Distortion effect, or even a cocked Wah. Bass tends to distort in a muddy, loose fashion, which is why many overdrive and boost effects seek to reduce bass. I like to bring the bass down so that it's barely or not quite broken up - the amp gain will compress it heavily, so you still get a chug sound on mutes, but the bass is well-defined and tight, allowing clarity in quick passages and chords but still sounding big and thick. A big dose of narrow midrange can make the tone sound quite like a transistor (typical stomp box) distortion - too focused and a bit fake. However, midrange is primarily where the distortion is happening - it's what gets the searing, harmonic-rich distortion we love. This is focused around 1 kHZ. A wide boost here will make the tone more "djenty" and squishy. Treble distorts well to a small degree but as you go too high, especially once getting above 3 kHZ, it can start making the distortion get crackly/gritty. I prefer to set a peak EQ around 2 to 2.5 kHZ rather shelving all the high-end upwards. Overdrive units do more than simply EQ the tone, adding their own character to the sound - there's no strong rules here - experiment with different effects to get a feel for them. Distortion effects can add some character to the tone by pushing the signal into a slight breakup which makes the main distortion stage distort a bit differently - usually a bit rougher and with more emphasis on pick attack. But I avoid running them hot enough to become saturated - the result is usually a sloppy mess.
The above generalizations are pretty consistent across different amps and types of distortion; however, every amp is different and require a bit of experimentation to discern how far you can change their character. For example, a Tube Screamer in front of a Marshall definitely changes the distortion from a somewhat rough crunch to a chugging thrash machine. But you're not going to get the same result out of a Fender Deluxe Reverb or a Gibson - you're more likely to get what sounds like you are torturing the amp. Similarly, you can't make a Rectifier sound exactly like a Vox and vice versa.
Kemper profiles are often captured with a real stomp in the signal chain. In these cases I avoid adding another Distortion-based stomp effect - you often end up with too narrow of a focus and things sound fake. However, EQ is fair game and usually quite helpful. Usually such tones will be a bit thin, and I'll use some EQ to fatten the tone up.
The Definition parameter on the amp profile is also directly associated with pre-EQ'ing the signal before the amp distortion occurs. You can crank this up to get a tighter, modern sound (an upper mid-range peak); but I usually go the other way with it, which I find sounds a bit more natural, although less aggressive. If I need to sculpt the distortion tone in such a manner, I prefer to use EQ which I have more control over.
The Graphic EQ is the easiest to experiment with. Keep everything flat then start turning up any particular band and pay attention to the resulting tone. Move it back to 0 and try another band. Now try the same experiment but cut instead of boost. The Studio EQ is also easy to experiment with. Set one of the parametric EQ's to +6 db and adjust the frequency up and down the spectrum. Repeat with a -6 db cut. This will give you a feel for what to expect, then you can focus on improving the tone.
I like to use a "hill-climbing" approach. I make a tweak that I think sounds good and store this as a new rig. Then I A/B the original rig to the tweaked rig. If the tweak is an improvement, I'll delete the original. If I prefer the original, I delete the new rig and start over. I repeat this process trying a few different approaches until it becomes difficult to find any tweak that actually improves the tone. Then I've max'ed out the tone, so to speak - I'm on "top of the hill".
Try Different Cab Profiles
These can totally resuscitate a DOA amp profile. Unless you are trying to get the exact tone of a real rig, there's a 99% chance you will find a cab you prefer over the default one. You can download TillS's cabinet pack here. These are mostly double-mic'ed Marshall 1960 and Mesa/Boogie Rectifier cabs. The Marshalls have some with T75's, some with V30's, and some with G12H's. The Mesa is the stock V30's, and it sounds huge. My personal favorites for the Rectifier cabs are 55, 56, 59, 63, and 66. These sound like there was more of that SM 57 bite in the mix. I also highly recommend grabbing Lasse Lammert's rig pack from the support page and saving the cabinets as presets.
Don't be afraid to tweak the cabinet parameters but remember to hill-climb (see above). High/Low Shift significantly affect the very high and low end frequencies, but also change the very nature of the tone. Start SMALL. I rarely go beyond +/- 0.2 here. Character has more wiggle room. I find increasing it can bring out more of that high-end shimmer, but I sometimes move it downwards too. Again, going too low/high will make the tone sound very fake, but in smaller doses can definitely make an improvement. For TillS Recto cabs, I find they have a particular low midrange roundness or resonance to them that can kind of dominate the tone and make it a bit dull. By lowering Low Shift to around -0.4, this resonance is pushed down to where you can't hear it and the cabs open up and get crispier. Similarly, increasing High Shift a tad (+0.2) can add in the high-end sizzle that is sometimes missing.
EQ'ing - Focus on a Mix Tone
Loop some drums and bass while dialing in your tone. If you are creating a track, definitely re-amp - you will hear things much better when you aren't playing. My philosophy is that a good tone should sound good in all situations - low volume, high volume, inside, and outside a mix. But a great tone will always sound great in a mix at a high volume, and honestly it's more important to sound good in a mix than good solo. Pulling that tone outside the mix and lowering the volume may reduce its charm, but you'll still be able to tell its a good tone. Comparatively, a "killer" tone you dialed up in the headphones at low volume outside a mix is more likely to sound like garbage inside a mix than if you took the opposite approach.
Always set the tonestack (bass, mids, treble, presence) controls before adding a Graphic/Studio EQ effect. Save those for fine-tuning. In some cases you might not need one at all, and this will free up an effects slot.
It's a good idea to browse through the EQ presets that come factory with the Kemper. There's a cut-through-the-mix setting that is a good template to make a tone that doesn't fit a mix fit in. It is essentially boosting around 1.5 kHZ, with smaller boosts to the surrounding areas with more focus around 1 kHZ. I have found moving this peak upwards can get you a thin-sounding tone, but sometimes this works perfectly for a lead, where you want to cut through with a sharp edge to the tone. Sometimes, I find I prefer a lower-midrange peak, but be careful not to add too much of that boominess that resides at the high-end of the bass frequencies.
Another piece of advice is to move the tone stack controls in opposite directions. For example, I may want to boost mids, so I cut bass to prevent too much lower mid-range woofiness or boominess to the tone. Similarly, you can boost treble but back off presence to get a brighter tone but without too much top-end sizzle.
Sometimes tweaking EQ leads you to believe you improved the tone, when what you are enjoying is the added volume. Try to compensate final volume every time you make an EQ change. This will keep you honest about your tweaks.
Make sure you have Clean Sense set low enough to avoid input clipping. If you are at minimum Clean Sense setting and still getting clipping, you need to reduce your guitar's output level. Some active pickups allow you to put a gain reduction jumper on the connector pins. Otherwise, you can lower the pickups, wire in a resistor (do research on this to make sure it is tone-neutral), run your guitar into an analog attenuator (like a volume pedal) before the Kemper, or just back off the guitar volume knob.
Always test for input clipping using headphones on a blank (or everything-disabled) rig and make sure you are not clipping output. Use your ears before your eyes - the input LED might flicker some red, but if you don't hear any clipping, it's not worth worrying about.
When using any kind of boost to the signal, whether it be changing a cab profile, boosting in an EQ, etc. make sure you are not clipping the output. I find that I get mild clipping as soon as the Output LED turns orange. I send via SPDIF, and have SPDIF set to 0 db. In my interface's mixer, I like the signal to be between -5 and -10 db. As soon as I even approach -2 db, even though it looks like I have more headroom, I can hear clipping. It's easy to test. Output clipping should be audible in even a distorted tone, and you'll know it's output clipping if you turn down the Volume knob and it disappears.
The Kemper is designed to be simple to use, and from all my tests it is impossible to get any kind of clipping inside the signal chain unless you have input or output clipping (besides EXTREME examples). So don't worry about gain staging all the effects in your chain - just use the Volume knob to avoid output clipping, and you're good.
Don't Fear the Reverb
For a high-gain rhythm tone, a touch of reverb often helps add a natural sound to the tone. Even if you just use the Small Room Reverb at 5% mix. Every other instrument needs reverb to sound natural; and even if the guitar tone sounds good without it, it may sound too dissimilar from the other instruments and hurt the mix. This is particularly evident when using headphones.
Don't Distort into Mush
Hey, I love distortion; and I break this rule all the time (let's be honest - crunch tones don't shake walls). Unfortunately, too much distortion will destroy your playing dynamics - for lead players this means you'll sound like 99% of the ignorable mob of bedroom players more worried about speed than phrasing and truly expressing yourself. For rhythm players, this shows up most when creating a multi-track recording. Even when only doing two tracks and panning full L/R, it becomes difficult to hear the notes being picked. Forget about accents. Double forget about those fancy M7 sus2 chords you just learned. Quad-tracking is even worse. Generally, the more tracks recorded, the less gain you'll end up using to get a clean sound. At extreme levels distortion adds too much noise and actually drowns out the pitch of the notes you are playing. Hence, the "wall of mush" analogy.
A good compromise is to add a compressor to the chain (or use the compressor parameter in the amp profile). It can be either before or after the distortion, but I find I usually prefer before. This makes the sound big and thick (especially for palm mutes), but allows you to use less distortion for a cleaner tone. If set correctly, the compressor will still allow heavy pick attacks to pass through, so your playing dynamics are clearly audible.
To be clear, pre-EQ and post-EQ affect the distortion tone and the frequency balance, respectively.
For Pre-EQ, usually there's no need to make narrow cuts/boosts - they tend to sound bad. I like larger cuts/boosts. The first thing I'll adjust is bass. If the distortion is a bit too rough and has a muddy, low-end breakup, I like to reduce bass. I like to use the Studio EQ and set the low shelf to about -2 db and start with frequency around 300 HZ. This should mildly clean up the low end. Then I reduce the gain to about -6 db and try to notice when the bass gets totally clear and tight. You don't want to cut too much or you lose tone. Then I start to reduce the frequency, trying to see where I get the most punch without losing tightness. Usually this is around 150 HZ, but it depends.
You can do the same thing for the highs but in reverse. Do a high shelf +4 db boost and slowly move the frequency downwards from 5 kHZ to around 1 kHZ. You should find a sweet spot that adds extra harmonic richness to the tone but isn't too sharp and harsh.
You can also use the mid-bands on the Studio EQ. Some suggestions are to cut around 500-800 HZ - this should make the distortion a little rougher. Or boost around 1 kHZ to 1.5 kHZ. This gives the tone a Tube Screamer-like effect, getting a bit more djent to the tone, but can sound a bit like a cocked wah pedal if overdone. You can also try the exact reverse to getter a smoother, creamy, liquid-lead tone.
I don't have a preference of Studio EQ vs. Graphic EQ here. Usually you can make settings on either one for the exact same effect, because I'm not doing any narrow or extreme boosts/cuts. I just find it generally easier to find the sweet spots using the Studio EQ - trying to adjust the Graphic means turning more knobs, but it does have the advantage that you can visually see how you're impacting the signal. One of my EQ presets is a Graphic EQ with all the bands set on almost a perfect diagonal line, so I'm cutting bass and boosting treble progressively up the frequency range. Then I use the Mix parameter to vary the impact of the effect.
Again, you can get similar effects from a Distortion effect with Drive set to 0 or a Treble Booster. I just prefer EQ because Distortion units tend to add some color/compression and EQ allows a bit more control than a booster.
There's no real right/wrong answer here. Your profile is already going to sound like your amp/cab/mic, which includes how you EQ your amp and your mic positioning. So that's your starting point, and in some cases; you don't need any additional EQ.
When you make your own profile, there's two kind of philosophies you can take. One is to try to capture a profile of a tone you've already tweaked to fit in your mix. So the profile includes all your boost pedals, maybe a mic pre-amp, and some DAW EQ adjustments. It's going for a very specific snapshot of the amp, and once you have it, you'd only make mild tweaks to sweeten the tone as you are mastering your tracks.
The other philosophy is to try to profile the amp at rather "neutral" settings, so that the profile can later be tweaked to make a wider variety of tones.
My guide was really targeted for those who (like me) aren't profiling their own gear, but are downloading other people's profiles; but it would also apply to the "neutral" amp profile mentioned above.
The best thing you can do to figure out what EQ tweaks can improve the tone are to record a DI and set it to loop in your DAW and send that into your Kemper. (Or just use a looper if you have one). When you aren't playing you definitely hear things better. Get some drums and bass going. If you absolutely can't get your own drums and bass or even find a suitable backing track, you can import a track from ___ band you like the sound of - in this case, pan that track 50% L and pan your guitar sound 50% R to get some separation. Now you can tweak EQ and really hear how it affects the sound in a mix.
If you demo a bunch of the most praised metal profiles out there (Lasse Lammert, Ola Englund, and Keith Merrow's rig packs), you'll notice they are all very different sounding. Keith's tones are very upper-midrange focused, Ola's are kind of thin-sounding, and Lasse's are more wide-open but they cover a lot of different ground from one rig to the next. Playing solo guitar on these rigs can definitely sound very off-putting. But if you listen to any of their mixes, the tone is big and powerful and pretty natural-sounding. This just comes back to mixing, which always requires context.
So for example, if your mix has keyboards, bass, drums, and vocals, you need all the instruments to find their spot in the mix. If you EQ'ed every instrument to sound flat accross all frequencies, the resulting mix would sound awful. Everything would be "on top" of each other, and "fighting for space" in the mix. This is even more the case for heavy metal music, where the playing is fast and technical and leaves little space. But that doesn't mean boost the kick drum at X frequency, the bass at Y frequency, and the guitar at Z frequency. The numbers are arbitrary. One mix might like to emphasize bass around 200 HZ, which means the guitars will likely need to dip around there. The guitars would then have very little punch and sound very thin on their own. Another mix might emphasize bass around 100 HZ. Now there's room for the guitars to have more punch. So it's a real balancing act, and there's a reason there are people paid to professionally mix albums.
As a learning experience, I'd advise you to do the looping/reamping suggestion I mentioned above, where you can hear your guitar tone in a mix. First tweak the Bass, Mids, Treb, Pres knobs to get the guitars to sound balanced - not too bright and not too dark with the right amount of overall midrange. Now use the Studio EQ and set one of the mid-bands to +6 db. Now sweep the frequency up and down slowly. Every now and then toggle the EQ on/off. See which frequencies help the guitars cut through and sit nicely the mix. When you've found good frequencies, you should be able to reduce the guitar volume and the mix will still be nice and full-sounding, but the guitars will have more clarity. Try the same test but use - 6db; which frequencies removed help make the guitars clearer. This will give you starting points on how to think about EQ'ing. You may find a spot that has the biggest impact on the tone - now you have to figure out how wide/narrow and how large your boost/cut should be. Start with subtle changes.
Always remember to try toggling your EQ on/off every now and then to see what it's actually doing and how it's contributing. Also, if you are boosting a lot via EQ, try turning the Volume parameter down a bit. Sometimes you THINK you like an EQ setting, but it's only because it's boosting the volume. A good EQ tweak should sound good even when it is reducing the overall volume of the guitars.
Also, you have to think about multi-tracking. Most metal rhythm guitars are double-tracked and sometimes quad-tracked. This will make a thin-sounding tone sound a bit thicker and dial back some harshness. If a tone seems a bit harsh and cold, try double-tracking it before tweaking. If you can't double-track, a frequently used trick is to use a delay with the minimum time and feedback settings to fake a 2nd guitar sound.
Remember that most bedroom tones you dial in outside of a mix tend to have more distortion and less midrange than tones that work well in a mix. Many of the guitar tracks on albums can sound a bit dull and weak on their own. This doesn't mean you should try to make your tone dull and weak; only that it gives you a starting suggestion - if your guitars sound too harsh or lack clarity in a mix, start by trying to reduce distortion and add some midrange.
I know this is a lot of info and it's a bit abstract, but I am not sure I could be more specific since it all really depends on your subjective preferences as well as what your mix is like, and the style you are playing.