Need suggestions on preamp

From a happy LRS owner. Get a high pass filter to roll off the input to the amp that feeds the LRS at 50 Hz. Get a good sealed sub - Rythmic or SVS. Set the sub crossover for 50 Hz. Your electronics are not the issue.

I think I’d 86 the Maggi’s and went with a cone based speaker with either a ribbon or beryllium tweeter, you’ll probably be a lot closer to that headphone crispness you’re looking for.
Check out:

Fritz Audio

Philharmonic BMR

or best case scenario…Have Soundfield Audio Custom Make you a set of speakers like the MMW’s… Call AJ and discuss your tastes and needs… Not as much as you think.

Any of these should certainly will get you closer than Maggi’s to your headphones you’re using as your reference. I just got rid of my Maggi .7’s… I fed them lost of Hi Current Power and still No Attack, No the Slam I was jonesing for, sure they sounded good but dull. Nothing wrong with the sound Maggi’s project, lots of folks love em, thought I would, but panels just didn’t work for me.
I think Cones or Ribbon based speakers will bring you to your happy place.

@g2the2nd - I plan on getting a Sublime 531. I plan on setting a -24db slope for 50hz. I want to pair it with dual Rel T Zeroes. I know also upgrading the crossover with better components should improve clarity.

@saboros - I’m kind of the same point. I think the Mark II has more power but the 545 was so good. Detailed and only when driven hard does it sound harsh and Maggie’s are meant to be driven hard. I guess stuff like Monitor Audio would have been more detailed but I would have had to spend 2 or 3x more to get the naturalness and soundstage these guys have.

@skiznfliz - I’ve heard Martin Logan Tweeters and those are exceptionally detailed but I find they get fatiguing after a while even with a McIntosh front end but maybe if I paired it with some like a Conrad Johnson it would be worth looking at again. I’ve heard the Philharmonics are a great value. What amp do you have paired with them? I feel like you need something more lush to counteract the tweeter. 

Depending on your location, you might be able to find a used Benchmark LA4 for about US $2,000. I'd consider that a strong contender for detail and exceptionally low distortion.

@hikaru126 

Check out my system … Everything is listed…
I had Maggi’s for 3 years…I tried and I’ve got an Ok set up and they just didn’t cut it.
If you’re experiencing the issues you mentioned, I really don’t think swapping out a preamp is going to give you what you want. The Maggi’s have a distinct signature and the few people I know that had them who got rid of them have told me the reasons I got rid of mine were pretty much their reasons as well.
I’ve got one buddy who likes his 1.7’s but of one of the others I know actually said to me they were the speakers that had the shortest time in his listen room… At the beginning I though they were great, then after some time realized their shortcomings. Hey, LOTS of Folks Love ‘em, just feel if you’re comparing them to the sound you get from headphones, they’re be short lived with you to.
A properly crossed over speaker will not be fatiguing and once I heard a properly crossed over speaker utilizing a Beryllium tweeter I was sold ! Buying an off the shelf speaker and hoping it’s going to work in your room is a long-shot, esp if you’ve never taken measurements of your room’s acoustic values so you know what and how to address in order to achieve synergy with your room & system. Your room is probably the most important factor in achieving good sound from your rig.
You have a lot to think about, AJ at Sound Field might be able give you some insight helping you make a better decision for your situation.