I have had this for a few months now and thought I could do a review. Still learning some of the features but I think I got enough out of it already and I have some thoughts to share..
This thing is well designed both for studio and live use. It is easy to lug around (3u rack), quick to set up, consistent sounding and has quite a few features to allow one to tweak their sound.
The Kemper controller is easy to use and well thought too.
2. User friendliness
I have found it easy to use. Navigating through profiles or the menus is easy and intuitive. The computer interface (Rig manager) makes housekeeping easy and the foot controller is easy to use too.
Accessing the several parameters is easy and the screen layout clearly shows what to do to change-navigate through parameters, menus etc (it tells you which knob to turn etc).
There can be a few parameters that could be confusing though (e.g. tube shape) as they are not available in normal amps. So accessing all options is easy but takes some getting used to to get a feel of what everything does
3. Build quality
Well, it does look a bit cheap but it is actually feels less cheap than it looks. I personally have faith in German engineering and manufacturing so I am not too fussed and it doesn't look like it's gonna fall apart so I think overall it is OK.
All buttons feel solid and responsive and so do the knobs. I would personally prefer a bit better knobs but they work ok.
The controller is more heavy-duty which makes sense since it's made to be stepped on. The switches are no worst than any pedal or amp foot unit I've used in the past.
There are plenty options to connect to PA, a power amp, IEMs etc. There are stereo/ mono options and you can have a multi-cable integration where you can assign what goes out each output via software (dry/ wet, amp w.o. fx, clean signal etc). It can also act as a IEM mixer and then you can use your IEMs through the dedicated headphone output which I think is cool. Only problem is that you need a stereo send from the PA for the band mix. It only has left and/ or right so if you get a mono send you will only hear the band in one side.
The controller connects to the main unit via an ethernet cable. Arranging performances is easy and intuitive and you can do that either in the unit or in the rig manager. You need to remember to store everything before moving on otherwise you need to start again.
Performance mode is ideal for having a dedicated performance per song with up to 5 rigs/ profiles (slots) which include fx but you can also assign more fx on top of that. e.g. you can have a clean and boosted clean in separate performance slots or you can add the boost by assigning it as a stomp effect in that slot. This is easy to do and saves slots.
There is no sound latency when changing slots/ performances although the screen graphics are slower to respond.
The soundguys love it as they get a direct sound and don't need to mic and, if the tones are dialled in thoughtfully they shouldn't have to EQ either.
In small stages/ venues some sort of on stage sound reinforcement is necessary otherwise the crowd at the front probably don't hear a lot of guitar so some means of monitoring is a good idea. I don't want to get into FRFR vs amp cab and the "amp in the room" thing but the monitor quality depends on the monitoring device (cab/ speaker etc). I use a matrix CFR12 for live and my yamaha h5s at home and I think both sound great. I tried plugging it to my Sound City OS Vert. 2x12 and it sounded great through that too, albeit slightly darker but much closer to a real amp feel. I didn't find I had to disable the cab in the profile when I did this;
In fact, I tried it and I wouldn't..
Once I booked a studio to dial the Kemper in with a PA in order to start gigging it and that particular PA and speaker combo sounded terrible so there may be times where what the FOH hears is not as nice as you'd think having dialled the unit in with a decent set of studio monitors.. But that's the venue's - soundguy's problem, I can't worry about it..
One feature that I am about to start looking into is assigning the EQ pre- or post-gain to simulate diff. types of amps. I think this is important when working with other people's profiles as the default setting is stack post-gain AFAIK and the EQ interaction sounds a bit digital.
In order to utilise this capability in the kemper I think one needs to investigate the basic architecture of the modeled amp.
e.g. what does cranking the treble does in a Boogie, a Marshall, a Vox, a fender etc..
Finally, when using different rigs within a song or even a setlist, caution must be exercised in balancing the EQ across all the profiles used. You don't want them all sounding the same but you don't want to switch between amps with drastically diff. inherent voicings otherwise you will throw the soundguy off and he will struggle with the mix.
Balancing volume across rigs is easy but it is good to use the ears too in conjunction with a means of db metering (DAW, soundcard etc). Having a constant value of db across every sound is only part of the game; you also need to listen for the EQ and make sure that all sounds cut. The interesting thing with all that is that I have to think more like a mixing eng. which is a good habit to develop I suppose..
5. Sound quality
I guess that as with every modeller, it depends on the quality of the preset or in this case profile.
What I think people need to keep in mind is that there are profiles that sound great but whether they will work with ones gtrs, band mix etc is not guaranteed.
e.g. When I first loaded the highly recommended MBritt profiles, I found most of the gainy ones sounded dark and stiff. I thought there was smth wrong with the unit but then I listened to a lot of MBritt's music and I found out that dark and stiff is smth that he likes. It matches his playing and band mix (Lonestar) but not mine.
So, a good quality profile doesn't necessarily means one can use it straight away.
I am not impressed by the selection of OD and boosts. I'm more used to echoplex-type boosts or others like tim, klone, RC and AC. I don't really like TSs treble boosters, rats and muffs so having mostly this type available in the unit is a bit limiting (unless I haven't discovered the boosts I like in the unit yet).
OTOH, there are great EQ options and I'm more familiar with tweaking those since I've played Mk-type Boogies with GEQ for a few years and learnt to rely on post EQ as much as the tonestack so overall I'm a happy bunny. The studio para EQ is particularly useful imho.
W.r.t. modulation FX, I think they are more than fine.
Once you tweak the profiles to a desired effect, the sound is studio quality indeed. Specially with a well balanced IEM mix, you can relax into it and if you are careful with your EQ and playing it feels as if you're hearing yourself through a record using a massive rack rig with all the fancy stuff. This experience is new to me and I quite like it.
-Great, studio quality sounds
-Light to carry and easy to set up
-Easy to navigate with plenty of tweaking options and easy to access parameters but not clear (yet to me) what some parameters do
-Good quality fx but limited OD-boost options
-Plenty sound-sculpting possibilities (EQ, compression etc)
-Seamless interaction between main unit and controller
-The sonic experience will depend on quality of profiles and some understanding of what to tweak for every diff. amp