Getting a punchy low end

Do you have an example of what you want to sound like? What do you mean by getting a punchier low end? Usually, for me, a tighter low end means using a high pass filter between 45 hz to 60 hz. Or, just playing harder would reduce low end and make things sound punchier, same goes for having fresh strings. Amps are going to have a lot of differing opinions but maybe try something with an Ampeg 810 cabinet

Perhaps try compression, or bandwidth-limited compression to "even out" all 4 strings? I'm not a bass player, though I own one, but my understanding has always been that bass guitar is pretty heavily compressed to even out the volume from each string... particularly for players that favor their fingers over a pick. Just a thought.

https://www.musicianonamission.com/bass-compression-trick/

I always record bass with an almost imperceptible amount of compression on it. It levels things out, keeps it punchy, and actually improves my performance.

Good strings and a nice bass are really important as well, IMO.

Nice even pressure with the fretting hand, just up next to the fret helps prevent the rattle of the string as you release the note and sounds cleaner and punchier.

Is it for in a band or recording? Anyway don't try to dial in on your own.

Ah, well that changes things, somewhat. I'd still use the compression techniques, obviously using the compressor in the Kemper to achieve this type of thing. Application of compression and some studio EQ to punch up certain freqs should help dial things in to be more "punchy"... at least that's my $0.02, as I'm not a live player... and barely a bedroom player, lately.

One note of warning, the built-in compressor of the Kemper is based on a vintage stomp style compressor and does not have the traditional parameters one would expect based on a typical rack or studio compressor. Pulling from the manual (Page 158):

 Intensity

Controls the amount of compression applied to your instrument. At zero position, there is no compression. In the first half of the Intensity range the effect will be fairly subtle, as the compressor will only cut the loud attacks of your instrument. Then, as you increase “Intensity” past halfway, you will start to hear the soft notes getting boosted as well.

 Attack

Adjusts the reaction time of the compressor. The higher the “Attack” value, the longer it takes for the compressor to kick in. This will let the first peak of the signal pass unaffected when you hit a string, thus increasing the percussiveness of your pick.

 Squash

This gives you control over the dynamic behavior of the compression. At the center position the compressor will work as you expect. When you turn “Squash” towards zero, the compressor will emphasize the first phase of the strings’ decay, resulting in less squash. When you turn it more to the right, the first phase of the strings´ decay gets squashed, and the volume sags. You will notice that the compressor recovers from squashing when you let the strings decay further - even boosting the sound a little, compared to when you hit the strings. Now, the compressor becomes noticeable!

“Squash” does not change the compression ratio, as this is always infinite on vintage stomp compressors.

Jeffro

Would be great to have just normal compressor settings that are industry standard.

Or, if your going to make it like a particular pedal, make it like the pedal with just those controls.

Quote from Jones1988

It's for my live sound, not recording. Probably should have mentioned that in the beginning

Mesa Boogie Bass 400+ is my fave valve head of all time. It's not my backs favourite through. It'll do what you ask though and there are a few profiles in the RE. I would also suggest the Trace Elliot V8, I had one for a while and it had too much low end through a couple of EBS 2x12's. It might have worked better with a couple of 4x10's instead but hindsight is a wonderful thing.