Yes I agree. I don't know why Harman Kardon are apparently so highly thought of, Any car I've ever had with an HK system has always sounded like cheap crap to me. The stock Bowers and Wilkins speakers in my Jag sound waaay better.
The reason I asked is in my Lexus wit the Mark Levinison sound system it uses an odd ohm rating and it is hard t match aftermarket speakers.
The sound is muddy, poorly reproduced not a vibration issue.