Hi Jim! I also have the THX in my Hybrid, got it two days ago, and although I love the car, I am dissapointed with the sound on the satellite radio. Voices are definitely where the issue is most evident- there's plenty of deep clean bass and great extension with the highs, but they really didn't do justice to the capabilities of the system with the EQ tuning. It sounds like there's a bump in the 150 -550hz range resulting in the muddy quality of voices- or instruments in that range.
(See my next post for an update)
I was able to fix the sound in my 2013 Fusion Hybrid SE using the tone controls: Bass +2, Mid -6, treble +4 and selecting driver's seat mode, but it seems that the tone controls don't fall in the range that needs to be adjusted in the Z. Since cutting the midrange back didn't help, I tried boosting the bass +5 and mid +5 with the treble +6 and that seems to be somewhat better.
By far the best auto sound I've ever had was in my 1994 Continental with JBL sound system- it was amazingly clean and had great bass and treble extension- sounded as good as a really good home stereo system. The sound in my 2008 Sable Premier was also very, very good (the audiophile sound system). Satellite radio was excellent, as it is with my other receivers- so it's not a problem with SiriusXM.
I asked a friend who works in Ford Design about this, how they equalize the sound, etc. and he said he'd ask around to try and find out some info on it. I know that when they were setting up the JBL sound in the Continental, they had a very high end listening room set up (Magnepan speakers, Crown or McIntosh amps, etc) and compare the sound in the room and then duplicate it with the car's EQ to get it right.
Edited by Brian V, 18 April 2015 - 02:24 PM.