Pedal and Peter

Thanks both.  I am back home for a bit, fired it up and started playing.  This software is fun to tinker with.  However, I think I will follow your advice and get a sound card.

Pedal - my system is a Marantz AV7005 pre/pro, with a SimAudio amp and Dali Euphonia speakers.

Sometimes - to the noob like me - I feel like Forrest Gump trying to understand what you guys are talking about.  At this point I comprehend well over 10% of it.... And, to the outsider, some of the stuff sounds...well...crazy.. SP1 making some sort of sonic difference?  But then I listen, and realize that either we are on to something...or on something

Pedal

I have to give you props for one of the most informative replies I have ever gotten on an audio forum. (Peters responses are good too!)  Thank you very much.  I look forward to getting back home and experimenting.

Regarding the card, is the reason for that just to get the RCA digital output?   The motherboard has optical out - will it make a difference?

Peter

This helps greatly.   One of the great benefits to XXHE in my opinion is this forum and your participation in it.  I am on the road for the next couple days but I am looking forward to tweaking some settings.   

One other question - perhaps a bit off topic - is I see a bunch of info about SPDIF and USB with converters and the like but I never see any discussion of HDMI.  I literally have all 3 options available.  Are there advantages to one over the other?

I will first admit that I am a noob at XXHE.  I downloaded the trial version and liked what I heard, so bought the full version.  I followed Peters guide for setting up - using Engine 3 and the recommended Q settings in there.  It is a relatively new computer - Sandy Bridge i3.  No sound card.  Music goes over HDMI to Marantz preamp.  The Marantz is the DAC.
I like the detail, soundstage, and feel of the music on XXHE.  But, when compared side by side with J River, the high frequencies sound rolled off, maybe a bit muted.  j River also sounds a bit louder - and I know that louder can be perceived as better.
It's hard to get good decibel readings on music, so I used a 1000hz test tone with a decibel meter to see if there was a difference between loudness levels, and to my surprise there was not, at least not at 1000 Hz.  Both J River and XXHE had similar dB readings on the test tone.
To further test the theory, I took my PC to a friends house who has an identical PC so we could easily switch back and forth between J River and XXHE.   This confirmed the high frequency roll off I heard previously.
Is there a setting I am missing here?