I know this thread is a little old, but I'd be interested if opinions have changed any? My personal experience (without doing any metering to validate my perception) is that the Kemper has a lot of low end filtering. I noticed this even with guitar on the Kemper when I was comparing it with my AxeFX2. Note that I ended up selling the Axe and keeping the Kemper, with no regrets. I had hoped at one point to build a full range rig with the Kemper playing the part of both Bass and Guitar Preamp sections (this was also a fail for me). I still prefer the tone when using the Kemper monitor out into the effect return on my 6505+ into Armaggedon 4x12 or Mesa combo vs. the actual amps' pre-amp section. But...there is just this sense of missing low end frequencies, that thump, that I haven't been able to achieve yet with the Kemper. My normal bass rig is a Music Man Sterling into a B7K, then to a Mesa Big Block 750 going out to a SWR 6x10 and an Ampeg 410HLF. My normal live tone is actually probably more mid heavy and cutting than is typical, but there is still that full low end that seems to be missing through my Kemper studio recording chain. Prior to the Kemper, my bass recording setup was typically at least three different channels. One was almost always from a Radial DI into an Ensemble and then the FlipTop model in the Amplitube Ampeg plugin. The others changed between the old faithful Sansamp (usually for dirt), a Chandler Germanium, Avalon U5, API mic pre, UA6176, or Neve pre for different colors and depth. I think that the Sansamp stuff is where I was able to get enough of those lower frequencies where it still had that weight that I want in my bass guitar tone. I've sold off much of that gear feeling confident that I would be able to get there with the Kemper. With guitar, although I notice the missing lows, I still get the best sounding, mix ready recorded guitar I've ever had. I think external processing or layering with other chains might be required to get the bass sound I want from the Kemper. I have only played around a little bit with the new parallel path, but so far I haven't had the results I'd hoped I would.
I am hoping that someone here has some tips on using just the Kemper to get that low end thump I'm missing, and if not, any recommendations on other outboard or virtual gear that has worked well for you in conjunction with the Kemper.
Cheers