Final ditch effort to improve my sound. Pls. help

Please help!

I feel I am not getting the sound I like out my system, so I finally have decided to throw a little bit more money at my source, as a final ditch effort. I sure hope it works. While not nearly as many of the systems I read about here, here is what I have. I'd be interested in what you think I should do to improve the sound. I have about 3000 to spend on either speakers or source or combination of both:

System 1 tube drive (for music):

a) Cary SLI-80 Integrated Tube AMP (I LOVE THIS)
b) 1 pair JM Lab Chorus 706S Bookshelf or 1 pair EPOS ELS3 Bookshelf (I go back and forth between these)

System 2 solid state driven (music on occasion but mostly home theater)

a) Audio Refinement Multi-5, Audio Refinement Pre-5
b) Same speaker set as above

Source for both Systems: Marantz DV8400 Universal
Onix Rocket UFW10 Sub: Its almost in the same class as REL when it comes to music I feel.

The Epos ELS3 are an amazing little speaker. I actually auditioned several higher end B&W, and NHT speakers (1,000+ range), but kept coming back to the Epos. So I'm not sure if I'm ready to part with these just yet.

Here is why I'm thinking I should improve my source before speakers. I borrowed my friends VPI scout turntable and played it through my Cary, and my EPOS - I was floored by the sound. I dint realize how dull my Marantz player was until then. So I decided that I am not going vinyl, because I have several thousand CD's -- so I started searching for a digital front end that would be most vinyl like, and my search ended with these three products. Meitner, DV-50, or 2900/3910 modded. Word on the street says modd'd Denon.

So APL or Exemplar 2900? Well the APL uses Cirrus Dacs, with very nice specs. And also has the advantage of the volume control built in, and balanced outputs, so it would seem that this may be the way to go. But I have not heard either, so this would be a leap of faith somewhat. All I know is that I am hoping the Exemplar 2900 would beat my Marantz. If it does, I think I will finally be able to rest from this relentless pursuit of nice sound.

What do you recommend? Change my source, or change my speakers? Or something entirely different.

The modded Pioneer OR a modded Panasonic would do the trick. There's also the modded Philips 963 -- but it's more expensive I think.
I haven't LISTENED to the Panasonic -- only heard abot it & read about it here.
Basically, a modded dvd player should set you back $<1000, leaving left over cash for music or speaker stands (that you probably have, anyway).

Later on you might think about the speakers; but a reasonably efficient, good performer would be expensive unless you go for diy...
The DV-50 & Meitner are very expensive. I would leave these out for now.
I'd suggest a Musical Fidelity Tri-Vista 21 DAC (there's a new one listed on Audiogon) and a transport of your choosing. You might even try what you have to see how it does as a transport for a reference point.
Have you done anything with the room? The room is essentially an extention of the speakers and can account for at least 50% of the sound quality. If you have bad acoustics you can keep throwing money at equipment and it will still never sound good. If the acoustics are good, even a modest system can sound stellar. If you haven't done anything with the room, a little bit can go a long way.

Disclaimer: We engineer and design the acoustics for listening rooms and home theaters world wide--so I am more than just a little bit biased here, but what I said about the room can make up 50% of the sound quality is true.
A modded cd player? Huh? Didn't that go out about two generations ago? Seriously, if you have that kind of money to spend on a cd source then go thee directly to your local Naim dealer and listen to the Naim CD5x. Then go home a little lighter in the old bank account and start listening to unbelievable cd sound on your totally reborn system. Maybe then you can think 6 months or so down the road about replacing those Epos with a set of Harbeths....then....whew.
I use a Cary cd-308 CDP with an Audio Refinement Pre-5 and AES-DJH (Cary) preamps. Sounds great with both, but the speed of the AR mates the best in my system. Amp is Pass Labs Aleph 30.
Not sure of your budget or if you are looking for another universal.
Many mnay options allegedly better than the 8400.

I do think modded units can offer exceptional value in some cases.
Do some reserach on various modders here, and decide what you think is worth spending on a source, and go from there.
I think improving your source is a smart way to go.
I don't mean to beat a horse here, cuz it seems that I'm always yammering on about it but I'd highly recommend an older Meitner DAC called the Museatex Bitstream. They pop used here on Audiogon, I own 1 but won't be selling it at all. If you do come across one, believe me its worth the wait. Send it over to John Wright. That dac seems ideal to what you're looking for. Several members of gon' might not engage in this thread but could attest to what a properly modded Meitner DAC can do to your system. Quite a few people who I admire for their honesty can vouch for that DAC. Worst possible case you could turn around and sell it, most sell their Museatex Bitstream DACs for what they paid for it orginally, on a few occasions they've made a profit.
The Audio Aero Prima is very analog sounding. I love mine. Sounds great with Cary gear as well as the Berning ZH270.
This might not be the response you are seeking, but just fyi, if your room happens to be the wrong size/wrong dimensions/have the wrong surfaces, you can try equipment until the cows come home or you run out of money or run out of time, and you might still not get there. It seems that it takes audiophiles many years to realize that the room can be a MAJOR contributor to the system's ability to reproduce accurate/pleasing sound, but it's a real consideration. Just something to keep in mind.
Borrow a high end source from a local audio retailer to determine if the source is the problem or the room. I have speakers in the same family the JM Labs mini utopias with a REL sub. I am using an older Cary 303-100 player and it's a good match. I am in the process of upgrading my player to Modwright Sony 999ES with the full mod. Total cost would be around $2,600 since you can find the players for about $500. Just another option. Check the latest Modwright review