Digital Front End: Critical Listening

I dunno, I've just beeen through a raft of digital upgrades in the last 8 months. I started with old Arcam Alpha / Assemblage 2.6 / D2D-1 lashup, bought a SimAudio Nova, then switched to Audio Note gear - ending up with an insanely expensive CDT-2 / 4.1x Balanced Signature combo. There is no way on God's green earth that I'd have followed that kind of bank-account-draining path if I hadn't heard a difference at each step of the way that was worth the cost - to me.

A lot depends on the rest of the system and (even more important, IMO) your values, preferences and goals for reproduction. I can understand that the perceived differences, both objective and subjective, may not be significant enough to justify the expenditure.

I have to say that the biggest jump in quality I heard was going from the Nova to the Audio Note transport with a 3.1x Balanced DAC. The change wasn't so much in the objective audiophile performance parameters, as in the amount of sheer music that seemed to be released. But keep in mind that this change involved moving to a totally different design philosophy and technical implementation, as well as a 3x jump in price.

Wow, judging from all the interest in this subject I guess there's a lot of us who are questioning the claims made by manufacturer's and reviewers alike.
First, a couple of things I neglected in the first post. I don't use any AC filtering or regeneration. I do use decent cables, synergistic research X series (approx. $200 per pair). Digital is not as good, the best monster cable and a custom AES/EBU on one end and RCA the other. I had a lond talk with an engineer on the subject of digital cable and he agreed with me that, in theory, it should really make a difference and that the hype was just that, markering hype.
I've taken apart my Celestion's and, as a speaker builder with decent knowledge of what is good and why, I think it's doubtful that the speakers are the culprit. The crossover use Solen caps and good parts all around.
I must say I was suprised to see so many of you questioning the sonic differences in digital gear. I also own a Sony SCD 777ES. Soon I'll be reorganising my system using different speaker placement in the room and different speakers, a DIY pair using the very best part I could find. I also plan to place the X-overs outside the enclosure so I can easily change parts throughout the voicing process. For speaker I'll be using E-speakers G3 ribbons and Scan Speak 5" mid, the revelators, and Scan 10" in a sealed WMTMW. This is my attempt at using what I've learned about speaker technology and computer analysis to build the best speaker I can. Maybe these will be able to reveal some more subtle differences.
Thanks for all the feedback.

Your DAC section cannot unleash the potential of the ML. Need an adequate DAC, price and quality wise to match what the ML can do.

I don't follow Bemoptil, I use a Levisnon 360S DAC. In the original post I said that I was comparing the Levinson to a newer Marantz DVD player, one of the better ones. To restate my original suggestion, maybe the newer DAC's are almost equal to older one's like my Levinson. There's about 5 years difference between the build dates. I'm gearing up to finally build a pair of DIY speakers that should be the last word in resolution, IMHO. Using the new E-Speaker G3 ribbon and 2 San Seak 15W's (5") per side in an MTM. The trouble, and what delayed this project so long is whether to add woofer and make it a 3-way, or using a separate active subwoofer per side. My room is only 12 by 20 by 8. With the 3-way design, I'd have trouble keeping the enclosure narrow due to the large volume required.

No opinion yet just my experience in the last month.

I figured it was time to let the B&W CDM9NT's sing. Speaker Cable upgrade. Huge difference especially in the bottom end. With B&K Pre and Amp. Interconnect upgrade difference ???. Then there goes the allowance Upgrade to Musical Fidelity A308 integrated. Nice sound out of my Denon DVD 2800 II which I had just purchased to replace my Denon DVD 2800. At this point I am a goner. Added Musical fidelity Tri-Vista tube DAC. After about a week of burn in with the Denon as the transport beautiful difference, more open and warm sound. Had trouble with the transport in the 2800II and returned it (Fedup with Denon). Purchased the Sony DVPNS999ES DVD SACD player. Beautiful fixed base transport. The music became brighter and not as warm as the Denon but very pleasing. At this point I blew a crossover and then a cone in the CDM9NT. My dealer loaned me a pair of DunAudio speakers so I could break in the system and still have music. Over the next week I A-B the Sony and the Tri-Vista many many times there was no audible difference to my ear. Reaching the frustation point a 2400.00 DAC aginst a 900.00 DVD and no audible difference. I took the Sony to my favorite audio store for a different ear and a listen. We used 308 Integrated to keep things the same. The only differnece was the Speaker Cable and the Speakers. Still no audible difference to my ear. There was to the salesman whom by the way I trust. A-B'd the Sony and the Tri-Vista for about an hour. Then we switched to the Musical Fidelity A308 CD Player using it as a transport nice difference over the Sony in all respects. A-B the 308CD and the Tri-vista DAC shall we say to my ear the DAC was warmer and more refined is it worth going separates over a CD player, I don't know yet I am looking for a good transport as I spent my allowance it will have to be used and mid-grade.
It will probably take another month to get the system together I will post again at that time. Remember to take the system as a whole.