Pairing of Magnepan 1.4 with Marantz SR7007

I'm pretty new to hifi (really didn't start building a quality system until the last few years and am a very budget conscious young adult paying off a mountain of student loans) and this is actually my first post on this site.  

I'm looking for some thoughts on pairing a pair of used Magnepan 1.4 speakers I recently purchased with my Marantz SR7007 receiver.  I recently came into ownership of a pair of used Magnepan 1.4 speakers for $250 locally and they appear to be in great shape.  I can't tell any signs of delamination of the wiring from the Mylar film, but I haven't taken the dust covers off of the speakers to check in detail.  I have replaced a pair of much more efficient Klipsch KF-28 floor standing speakers which I purchased open box from Best Buy with the Magnepans which I was running off of my Marantz SR7007 receiver.  I knew the sound quality and detail would instantly be better as I had heard Maggies at the local audio specialty shop in the last year.  But it is still surprising every time I start the system up and hear the difference.  Just for a reference I am mostly streaming Tidal lossless through a Audioquest Dragonfly Red or Meridian Explorer 2 DAC directly into the aux port on the Marantz.

The Magnepans are currently set at a crossover of 60 hz with the bass being picked up by a pair of entry level 8" Klipsch subwoofers.  Right now I'm trying to determine if there is really any need to consider upgrading to include an external power amplifier in this setup.  I believe the Marantz is rated at 125w into 8 ohms, but not sure if the power supply on this unit has the ability to really provide the current needed for the mangepans or not.  I so far haven't had any issues with the Marantz shutting down or showing signs of excessive heat (at least any warmer than normal).  I usually listen at moderate levels without cranking volumes too high as I am in close proximity to neighbors and conscious of protecting my hearing.

Would an external amplifier with a better power supply connected to the pre-amp outputs from the Marantz provide a significant benefit?  Would there be a significant difference between Class A/B and Class D in this application?  I know Class D technology has come a long ways, but has it gotten good enough where it can compete with Class A/B in the same price category?  How would external amplification likely manifest itself in the sound of this system?

Any suggestions on a good budget amp (new or used) that would be good for this application?  I've had a friend suggest Crown amplifiers for the good amount of power they will produce.  Other have suggested a good NAD or Rotel amp.  But not sure I'm in the market to spend $1,000+ now.

At the end of the day, I will likely enjoy these speakers for the time being on the Marantz as it really doesn't seem to be a bad combo at all.  I'm not completely sure the upgrade that might be realized would be worth the added cost if it is likely to require an additional $1,000+ investment (keeping in mind that I only paid $250 for the speakers).

you want good current delivery into 4 ohms - Maggies are otherwise very easy to drive as they are a nearly pure resistive load, not a complex impedance

and... just use your receiver

hopefully, you will be hooked and then want the HIGHLY improved 1.7i Maggies

at that point, I'd be looking for a nice Class D (see the thread titled Class D is just like candy) or an Emotiva amp
If you like sound just drive it till it blows and then buy an amp rated to 2 ohms .
It might blow or might not, I had 1.4’s for several years , at times they go as low as 3 ohms easily .
Class D is fine if you get a tube preamp, 1.4’s show their best with amps
at least 300 per side at 4 ohms .
Thanks for the feedback. While I think the Marantz will work for this application, I'm curious what would happen with more amplification. I've been looking at the Crown amps and think I might pull the trigger on one of those. Probably just purchase through Amazon and take advantage of their return policy if the results of adding a higher current power amp doesn't provide significantly better results.

I'll be sure to share what I hear and ultimately decide.
And I'm kind of partial to the Marantz and would prefer taking steps not to kill it as I really don't intend to be in the market for another $1,500+ receiver anytime soon. lol.
I just got the Crown XLi 1500 in today and set up with the Marantz as a pre-amp.  I have to say it is quite a significant improvement for this application over the built in power amp in the Marantz.  The extra power and current from the Crown seems to really add a lot more control over the mid and low end of the Magnepan speakers and definitely has the ability to drive them to much higher output.

I learned a bit about pairing the preamp to the power amp during this exercise and think this is a really great pairing for the cost of the Crown amp.  The Marantz is rated for 0.4v on the pre-amp outputs while the new Crown amps have the ability to switch the impedance rating from 1.4v to 0.775v which is a new feature included on the XLi series so that it is more compatible with consumer products.  The 0.775v setting makes for a nice pairing with my system.  It still allows me to reasonably amplify the signal to around 300 w per channel at 4 ohms into the Magnepans (not the full 450 w per channel into 4 ohms if I was able to deliver the 0.775v input signal), which is really more than enough.  Not looking to kill my hearing before I'm 40.  

The benefit here seems to be that the Crown still has a lot of head room over this limit so it is not likely that the Crown will clip (though the pre-amp in the Marantz may if driven too hard).  I'm just getting generally good, clean power and sound while it is producing a pretty good stereo image and fairly detailed sound stage.  I think this one is a keeper for my system at least for a while.  I think the low end could be a bit more defined and separated on this amp, but is it terrible?  Not at all.  Would I like more detailed low end?  Of course..... but is the difference worth the added cost of a true audiophile grade amplifier (easily costing 10 times as much)?  Probably not to me.  Maybe my tastes will change after I get my mortgage paid off and am no longer paying $1,000 a month on student loans.  LOL.

Most importantly, now I feel a lot more comfortable turning up the amp and letting the Magnepans show me what they are really capable of.  I think for $250 speakers, $300 power amp, $250 for a pair of Audioquest Type 4 speaker cables and a few other Audioquest RCA interconnects and throwing in the Marantz to tie it all together on the front end, it is a really good system for maybe a total of less than $2,000 (including the Marantz).  It isn't bad.  And to steal a quote from someone on another thread, "While this may not be the absolute best system or sound, I'm not exactly punishing myself listening to it."  LOL.

Thanks for the feed back on this post.