Replacements for Dynaudio Floorstanders

Well you ended up answering your own question didn't you.

"As for my Benchmark DAC, I'm going to stick with it for the immediate future because it's my newest component at less than two years old. It DRAMATICALLY improved the resolution in my system, though I'll admit it left my sound a bit thin and definitely trending on the bright side"

I'm curious, why would you "stick with it" if you've now come to the realization that the Benchmark is bright, and don't like the way it sounds, and it's causing the issues that you have with your system? Keep it cause it's 2 years old?? Not to be rude but your logic doesn't really seem to make any sense. Just sell the thing and move on. You can probably get $700-$800 for it. pick up a new W4S Dac1 for $999.00 that will crush it, across the board.

As for the Levinson 383 I'd think hard on that. The 383 is long discontinued, no warranty, and Harmon is known to have terrible support for older Levinson products, just poke around in the discussion forums about Levinson customer service issues.

A great choice in an amp that would match up well with your Dynaudio's would be a Plinius 9200 plenty of power great sound, excellent match.. They typically sell for $2500.00 -$3000.00, less than a 383 and pretty much bullet proof build quality.

my 2 cents(considering your room acosutic is OK and you like your speakers)-
change your dac to soemething more warm and liquid.

audioqest cables is on the hot side, kimber 12tc would do the job making sound fuller.

pass labs class a amps could be a ticket. most Ayre would not go hand in hand with krell bass- when you are used to it you will miss it.

Erikminer: my logic is that I'm in grad school and don't want to spend too much money. However, I'd like to pin down what exactly I should get in the future, so I can keep an eye on Audiogon. Also, my intention was never to replace the Benchmark, nor the Krell, but the speakers. Even if I've pinned down that the speakers are not really the issue, I'd much rather invest in a full(er)-range speaker (ideally one that is a little warmer) that will serve as the anchor of my system for the future and deal with the Benchmark and Krell at a later time.

Might not make the most sense, I'll grant you, but this is a work in progress, and I haven't laid down a dollar to change anything as of yet. I just wanted some feedback! Thanks once again.

A fuller-range, warmer speaker would be a Vandersteen 2 or 3, and good values.

It might be due to setup or the room. How big is your listening room and how are the Dynaudios set up in the room? Are they close to wall boundaries? Are your equipment on a proper rack? Move your speakers around and try treating the room for a free fix. If all else fails then replace the DAC and/or the amp assuming you like the Dynaudios.