Regarding the Harman Kardon HK990

Hi,  I'm a newbie.  I have a HK990 that was purchased off of Audiogon by a friend (dead now) and he said it was special, as he already had a HK990.  Supposedly it had something special done to it?  Anyone here remember any conversations about it?  His wife is asking me to liquidate his stuff and am trying to accommodate her. Jack Fletcher was his name, maybe I can get info from the admin?

Cheers, and good health...

Phil Marusek  Temp Esquire......and Estate manager for Jacks stuff.