From a review:
"The Phase Linear 5000 combines excellent receiving capabilities along with a unique linear expansion circuit which compensates for the problems associated with FM broadcast. Consequently, the 5000 FM Tuner delivers dynamic range and sonic quality audibly beyond that which has been available."
https://stereonomono.blogspot.com/2012/10/phase-linear-model-5000.html
Not quite the Bob Carver circuitry (the PL5000 was an A.P. Van Meter product introduced in 1976, discontinued in 1978 by the 5000 Series II and that one in 1979 by the 5100 Series II). But they were on the right track with the PL5000 series, I had one and it was a great unit. No doubt the Carver TX-11 and the NAD 4150 were way ahead of their time in 1983!