NRG PA1 preamp. Anyone heard about it?

I came across a NRG Preamp at a shop today. I have never heard of this brand before but the owner told me this amp used to cost over $7k new and it was perhaps one of the best preamp he has heard.

I tested it (along with other components) but the sound was pretty bad. I can't make out if that was the preamp's fault or that of other components in the system.

Has anyone heard of this preamp before?