Kemper Profiling Amplifier PowerRack

Early days yet but this is my experience so far.
I was interested in the concept, read the reviews and had been considering getting a Kemper to profile my Mesa LoneStar Special to use as a backup for gigs (or replace it completely because the Kemper is much lighter and should be more reliable). My LSS actualy blew up a few weeks ago so that pushed me to buy the Kemper anyway. The user interface took me some time to get used to - after a few days I am still not proficient - even though I have worked in IT since 1980 - it's not that easy. An Ethernet or USB connection and a Web UI would probably help a lot here.

I have profiled my LSS Preamps and the Kemper gets very close but is less "airy" with slightly less "sparkle" - this is just a/b through the desk into headphones. This has nothing to do with power amp/speaker coupling yet, which I have not tried to emulate or profile (that's a job for a soundproof room next week). The touch reponse and dynamics of the profile were impressively close to the LSS preamp once it's gone through a few stages of refinement. I found that by playng single notes rather than chords as instructed during the refinement process it got closer to the orginal dynamics. The effects are excellent.

I tried the PowerRack for the first time at rehearsal this week. I was using one of the stock AC30 HW profiles included in the Kemper. It sounded good but I was disappointed to find that the specified 600W RMS supposedly "on full" was not as loud or as punchy as my repaired LSS running close to it's max at 35W RMS. These were both tried using the same Celestion 8 Ohm 75W 1 x12 Black Shadow speaker. I actually need an amp as loud or slightly louder than the LSS to keep up with my drummer so, until I have figured out what I am doing wrong with the Kemper (although it is undoubtedly a *very* useful piece of recording kit), it looks like the Kemper PowerRack will remain only as an emergency backup for live work and my "poor ol' back" will continue to suffer the weight of the LSS as my main rig.


Note that I fitted the Kemper into a 3u rack case to protect the front and rear panels for transit. The jack sockets on the rear are plastic and in my opinion are a bit flimsy for live work. I accidentally broke one on the bench before I had even powered it up for the first time and I am a 7-stone weakling - not a gorilla (maybe that's why I think the LSS is heavy). I chose the rack format over the head because I dislike the dimensions of the head. The case of the head is definitely tougher than the rack but I think the Powerhead probably uses exactly the same sockets on the rear - so you have been warned, take extra care!