Hello,
Just got my KPA, and been playing with the stock profiles and been rather impressed by the sounds I get. I have a few tube amps and today I decided to start profile them. I live in an apartment and I do have forgiving neighbors, but still use an attenuator to keep the total volume beyond ear damaging levels. So the signal chain is: R-101->Rupert Neve 517->RME UFX->KPA and KPA to the guitar amp of course. I've already set up the mic placement so I just profiled and refined without listening to the reference amp through the KPA. I profiled a MK V and Orange Tiny Terror, and listening to the profiles afterwards was surprisingly good even without an attenuator.
Anyway, I profiled a HI Watt (50W) as well, first clean that gave a very nice profile then a almost maxed out version. For some reason the maxed out version was terrible, with the kind of distortion you get when you overdrive a solid state amp. When listening through the reference amp from the KPA there is a noise sounding like a blown solid state amp, that also affects the profiles. Turning off the KPA and then back on, the problem more or less goes away. I also attached an SM57 directly to the KPA input and could not hear the noise. It's almost as it seems to be worse after you've played with a few profiles before switching to the profiler.
I've checked the UFX outputs and the mic, sounds perfect when not going through the KPA. The cables are also good.
Can this be something specific to my KPA, or has anyone else experienced problems when profilng through a mic preamp?
Torsteink
It is not clipping, and I keep the signal level rather conservative. It does not matter if the line level output is set for +4dBu or -10dBv from the UFX, and I also tested with a SM57 straight into the KPA. It works fine for a while, like when the unit is cold, but after a while there is this distortion added to the sound, and the signal level does not really matter. Almost like a bad connection. I am running the 1.5 version, but if I am the only one experiencing this maybe my unit is not totally at par.