Likely culprit for harshness at higher volumes?

I'm going to go out on a limb and say that it's probably your speakers or the room. The cables you describe should work just fine. I recently compared a set of $2,000 Nordost cables to a $7 pair of hardware store cables and certainly couldn't tell $1,993 worth of difference, at least for my system that I have about $5,000 in for the main stereo components. Cables make small difference and what you're describing sound like they are more significant in scale. Keep in mind that there are many members on the forum that have systems where cables might make a significant sound difference, but I don't think it applies to you and me. I'd suggest going with something like Blue Jean cables if you want something that's respected and affordable.

Is there any adjustments on the pre-amp or amp that might be turned up too much. Isn't it possible to have the inputs too sensitive?

Saru - I read through the manual for your pre-amp and didn't see anything like what I was referring to. On my truck subwoofer amp and also some of the amps in the audio system at my church have adjustments for the input sensitivity that can really change the way things sound. I think some seperates have this type of adjustments, but not all. I was thinking that you might have things oversensitive and amplifying something in the digital recordings.

You might actually try allowing your pre-amp to do some processing rather than bypassinge everything. On my Integra 50.1 receiver I generally listen in direct mode when I'm in audiophile mode, but for some recordings it simply sounds better in stereo mode where the signal gets processed a bit. It may be similar for your system but for different reasons.

I highly doubt that you'll hear much if any difference from any cable swaps you make unless you are currently using a damaged cable currently or you're getting a lot of interference in an unshielded cable.

Saru - There are differing views on jitter, and digital in general, that go to the extremes on both end. This is just another example of an audio topic where you need to be open to the idea that very few of us are correct about everything and the truth is likely somewhere in between the extremes. Some will argue that digital comes down to a 0 and a 1 in the signal and quality only matters once it becomes an analog signal and others will spend thousands on digital components and such. Keep an open mind.

The guys at my local Hi Fi dealer were always telling me to ignor the specs and just listen. The owner gave me some specific examples of equipment that had specs that were the opposite of what you'd expect based on the sound. I'm an engineer so I like specs, but like all metrics they can be made to say whatever the manufacture thinks you want to see.

Try hooking up an iPod or other mp3 player via a mini plug to RCA cable and see how that sounds. It shouldn't sound a clean as your CD player, but might help to determine if the CD player is part of the issue. You could even rip some music in WAV format so that it's not compressed for a slightly better comparison.

Here's a few CDs that I have that I consider to be some of my best recordings. I think they may be something that you'd enjoy listening to. Amazon.com sells all of them.

Bach: The Brandenburgs - Jacques Loussier Trio

Violin Solo - Ning Feng

Holst: The Planets - Gustav Holst (Decca, Los Angeles Philharmonic Orchestra, Zubin Mehta)

The Canadian Tenors

Tanking a Chance on Love - Jane Monheit (the 1st song on this CD was a favorite demo for the salesman that sold me the majority of my audio system. He would jokingly say, "If you don't like this, get the hell out.")