thank you i don't know well what is a FRFR and i don't know if the kemper cabinet is one of them
"FRFR" is a marketing term for a PA-style monitor cabinet. "FRFR" supposedly means "Full Range Flat Response", so the intent is to act like a very good studio monitor, PA system, or home stereo - very accurate reproduction. In reality, most cabinets that claim to be "FRFR" are anything but.
In my experience, the best way to achieve this is to purchase the best self-powered PA wedge you can find/afford. The pro audio world has been building monitor cabinets for decades, they have the technology and costs well sorted out, and the performance you get very closely follows the price point. In contrast, most of the cabinets marketed as "FRFR" are low-end PA cabinets that have been re-badged, and they really don't sound very good. This is not universally true, as there are a few at the higher end of the range that are relatively accurate...but most are not.
In the end, though, think in terms of balancing what you spend on the monitor with the Kemper. The KPA is a top-tier, no excuses digital amp. It should be paired with a monitor of similar quality, and that's not something that you get for $500.