FWIW, my system employs the NAD 7600 Monitor Series Power Envelope RECEIVER (which combines the 2600 power amplifier and the 1300 preamplifier with the 4300 tuner—all flagship components for NAD at the time, which was the late 1980s). I have never looked back. The unit I had as an original owner finally began to fail in various ways after 30+ years of daily use (and transportation to various dwellings in various states). Because it was hard to find a replacement by then, I auditioned various integrated amps, including several that are very well regarded; I've got audiophile friends, one of whom owns the best shop in the county, so I had lots of sweet options to choose from. None sounded as good! Finally, eBay came through, and once again, the NAD 7600 powers my system. Nothing else, in my experience, was as transparent, with natural timbre of instruments, vivid soundstage, and tremendous power.
Just sayin'....