Resolution Audio Opus 21 questions

Greetings all! I have a RAO 21, and am a little un-happy with volume(loudness), dynamics/slam. Using modified Odyssey Stratos Mono amps, Odyssey Lorelei speakers, VD Revelation speaker cables & TG Audio i/c, Electraglide SOTU p/c's. My question: Is anyone using a pre-amp with the Opus 21? Does it/will it help in the above mentioned categories.
Thanks for your help.
I am very happy with mine in all respects actually.
I will state that I have the unit running into my Ayre K-1xe preamp via the DIN output on the Opus 21. (The DIN output bypasses the volume control, and is the absolute best way to get the best sound from this unit, as per Jeff Kalt, the wner of Resolution Audio.)

Also, I feel that the Opus 21 is somewhat analog sounding, (which is how I like my sound to be actually), and lacks the ultimate digital dynamics that some units have, such as the Ayre C-5XE, which has great dynamics, but sounds very digital sounding to me. (It might be that you prefer the dynamics of that type of CDP, over the analog sounding ones, like the Opus 21.)

Good Luck in your search for your CDP.
I much prefer the Opus with a preamp in my system. I tried it direct to my VAC monoblocks and it was ok, but I gained clarity and resolution with a preamp (Dodd pre). Also, I didn't feel the Opus had enough gain run direct and the pre helped in that regard. I also use the DIN out of the Opus, though in A/B testing I thought the differnce as compared to using the RCA outs was negligible. This is obviously a system dependent issue, since there a many here that prefer running the Opus direct.
So the Pre-Amp is acting like loudness button? Where did Jeff Kalt say it was better thru a Pre Amp? Better how? More like the ultra compressed music most people think is natural? How can adding stages to the signal path improve anything but the bottom line of Pre amp manufacturers?

I've done a good bit of research on this topic lately, as I run a CDP directly to my amp. Here are the two key points I've gotten from the preamp advocate camp:

1. a preamp greatly increases the soundstage depth (though the advocates disagree as to why); and

2. the volume control components in CD players are much lower quality than the other parts in order to keep cost down.

The experience I have in this area is of such a nature that I'm not comfortable commenting either way, but the report of what I hear from manufacturers, dealers, and other users are what I've reported here.
Thanks to everyone who responded including email responses. I greatly appreciate the sharing of your time and experience. Seems that there are 2 distinct sides to this one...since I've already tried the direct route I will give the pre- a shot. Thanks, again.