Revel F-30/ large or small

I agree with Kal....I also think "overdriving" them is tough to do if you're using quality amplification. I'm driving my F-30's with a Pass X-250 and they seem to handle power without complaint.

..."However at "loud" volume levels, I am concerned that I may be over driving them."

This is a common problem wiht audiophiles/enthusiests who run full range speakers as such for HT! Often your not only under-amping them, but your passive speakers have a hard time with control and dynamics for DD/DTS becuase of the inificiency of the system! Powered sub's, and setting PROPERLY SET UP SPEAKERS as "small" is a much more dynamic experience with passive speakers! Bass managment is a must! You will get much better authority and power handling with the Powered sub, and your speakers amps will only be handling upper bass on up, which is much more efficient! You're effectively partially ACTIVELY BI-AMPING your system when you do this! It's much stronger.
A good compare/contrast here, would be you driving your F30's full range side by side vs. a pair of either full range Def TEch BP2000's, Infinity Prelude MTS's, or NHT VT3 towers! The above mentioned other speakers will dynamically stomp your speakers!...especially on ultra dynamic Rock and DD/DTS movies!!! These speakers are using powered active woofers with large drivers and amps! Your passive set up method is less efficient, potent, dynamic, and strong. That's the way it is.
Many, many, many people simply plug their 2 channel full range passive system into a DVD player, and think they have the pinicle of great HT sound!...they're mistaken.
Heck, even large commercial theaters use massive ultra high sensitivity horn speakers and cross em over to big 15/18" powered subwoofers! There's a reason...it's more dynamic, and efficient!...not to mention potently powerful.
So, what do you want? Do you want, plolite, strained, muddy, blown out sounding bass for ultra demanding HT material?...then you run things "as is". Otherwise, my suggestion(making sure you have a good amp) is to make sure they're placed properly for best bass coupling with the room/your seats, cross em over as "small"(maybe even bi-amping would help greatly if you get radical), and let active powered subs handle the "dirty work"! You'll like what you get, trust me.
Another "test" is to run some very dynamic rockor Techno "your way" vs., "bass managed/subwoofer way!".
Another consideration, and STONG REASON why you should "bass mangage" is that standard audiophile speakers like yours are lower sensitivity compared to the much more dynamically effortless high sensitivity active, horn, pro audio, and similar spaeker designs!...so they need all the help they can.(I think they're like 89/89db or something, compared to high 90-115db speakers!) good luck

Wow!!! I sure do appreciate all of your input. I believe that the bass is "tighter" when I run the Revels "large". However, there seems to be a lack of deep bass for the DD/DTS movies.As far as amps go, I use a parasound with 220 watts into 8 ohms and about 320 into 4 ohms. Based on what I am hearing and what your saying, it sounds like I would be better off using the "Small" setting. Thus the question remains, am I not loosing low end when listening to 2 channel music? Once again, thx for your advice. ( I use an older Krell HTS processor that only allows LRG or SML settings, with no other bass mgmt)

There may not be anything lower on most regular music. Why not set them as Large for music and Small for DD/DTS?

Yes that will work. With the Krell preamp it must be set to small or large. I guess I can switch back and forth. Once again thanks for taking the time to rply.