Using a Kemper, most people first touch the Rig selection.
Then Gain. Then EQ.
The effects beyond.
Input is usually left for last.
A plain section placed small at the left edge of the screen. Quite a few forget they've set it.
But much of why the same profile sounds different from person to person is here.
Input is the "entrance" itself
The Kemper's signal starts at the guitar.
The guitar's output first passes the Input section — before it reaches the Rig.
So Input is like a checkpoint before the profile.
How the signal is received here decides how it distorts afterward.
However much you re-choose the Rig, if the entrance conditions differ, the sound that comes out won't be the same.
It's structurally the same as the sound changing whether or not you place a pedal in front of the amp. The only difference is that it happens at the digital "entrance."
Which is exactly why Input can't be taken lightly.
What does Clean Sense align?
At the center of Input are Clean Sense and Distortion Sense.
First, Clean Sense.
Clean Sense is a setting for aligning the volume feel of clean sounds.
Output level differs by guitar. A single coil and a humbucker differ in the strength of the signal sent to the amp when you strike a string.
Even the same profile, connect a high-output guitar and the clean sounds loud; with a low-output guitar it sounds quiet.
Clean Sense is an adjustment to fill this gap.
Raise Clean Sense for a low-output guitar, lower it for a high-output one. Doing so, the clean volume feel aligns even connecting multiple guitars.
Important here: Clean Sense isn't a setting that directly touches "the amount of distortion."
It's a setting for matching the clean-side baseline. Not a setting that decides the distortion character.
What does Distortion Sense do?
What relates to the distortion side is Distortion Sense.
Distortion Sense adjusts how the guitar's output level reflects into the distortion amount.
Raise the value and higher-input guitars distort deeper. Lower it and the distortion difference from guitar-output difference shrinks.
The factory baseline is decided assuming a particular guitar.
Connect your own guitar there and a stronger, or weaker, signal than assumed comes in. Then the profile receives a signal different from "the signal it received at design time."
Distortion is sensitive to input strength.
Input a little stronger and the distortion deepens. A little weaker and it shallows.
Distortion Sense is the knob that decides how to handle that sensitivity.
In many cases, leave it default. But when using a guitar with extremely high or low output, it's worth revisiting.
Why does the response change when you swap guitars?
Here, return to the profile itself once.
What is a Kemper profile made of?
The profile itself is made mainly by the Kemper's analysis signal and the amp/cabinet/mic response.
The "tone itself" of the guitar played when making it isn't fixed and burned into the profile.
What's fixed is the response — what kind of box the amp, cabinet, and mic respond as.
Into that box, at play time, your guitar's signal enters.
So the finished profile's response changes with the guitar signal input at play time.
Even the same profile, play with a high-output guitar and it's pushed and distorts; with a low-output guitar, margin remains. Pickup type, volume position, playing strength — all become differences in the signal reaching the entrance.
The phrasing "the sound profiled with this guitar" is inaccurate.
Correctly, it's this:
The response when playing this profile changes with the input signal of the guitar used.
And what first receives that input signal is the Input section.
"Aligning" and "changing" a setting are separate
Here I want to avoid misunderstanding.
The purpose of adjusting Input isn't to make the sound better.
It's to align the baseline.
If the volume feel and distortion output align even swapping multiple guitars, you can correctly compare the differences of the profiles themselves.
Conversely, with scattered entrance conditions, you can't tell whether you're hearing the profile difference or the guitar difference.
Clean Sense and Distortion Sense are tools for making that distinction.
There's no "correct" setting. But it's better to make clear what you're using as the baseline.
Judge "this profile distorts too much" or "thinner than expected" with a vague baseline and it may be an evaluation of the entrance, not the profile.
Why CSL aligns input conditions
CSL records real tube amps and provides them as Kemper profiles.
When recording, it emphasizes aligning the entrance conditions.
The reason is the same as what's written above.
If the input signal differs, the same amp distorts differently. So without aligning what signal it was recorded with, you can't compare conditions later.
CSL uses reamping even for the refine at profile creation.
Rather than a human playing each time, using the same DI signal — to align the input conditions.
When a person plays, that day's picking and hand habits ride on the input signal. That itself isn't bad. But in scenes wanting to record with conditions aligned, it becomes a wobble.
Reamp and input the same DI signal and the entrance is the same each time.
This idea is continuous with the user's Input setting.
CSL aligning the entrance at recording, and the player aligning their guitar's baseline with Input, are doing the same thing, only in opposite directions.
Both are work to not mix "the profile difference" and "the input-signal difference."
In short
The Kemper's Input is a plain section.
But it's the entrance before the profile.
Clean Sense is a setting to align the clean volume feel from guitar-output difference. Distortion Sense is a setting to adjust how input strength reflects into the distortion amount.
Neither is a function that flashily changes the sound. They're functions to align the baseline.
A Kemper profile's response changes with the guitar signal input at play time. So there's meaning in grasping how you've set the entrance.
Before evaluating a profile, first look at the entrance.
Then, whether you're hearing the amp difference or your guitar difference gradually becomes separable.