I have three digital sources

I also have an Oppo player and an AN DAC and am completely amazed you find the Oppo superior.

My first question is what kind of music you are listening to. Please tell me, and I'll respond with my thoughts.

Ok. If you would have said you listen mostly to rock or even more processed modern pop, rap, etc. If you are listening to well-recorded acoustic music I am indeed quite surprised.

After some thought I would say it is likely you are legally deaf.

Just kidding. My AN DAC is the kit 3.1 Signature, roughly equiv to a factory DAC 3 I believe. To me it excels in smoothness and correct timbre. I hear this most (in relation to other DACs) in horns, which are so difficult to reproduce with correct harmonic balance and integrity. I find other DACs - especially ones that don't employ the AN NOS/filterless philosophy - to without except sound a bit thin or bleached in harmonics on horns.

It's been awhile since I've compared anything else but two recent players were a Marantz SA11 (pretty good on SACD) and a Modwright Transporter.

IME most decent NOS/filterless DACs get the smoothness/naturalness and the timbre fairly correct. Where the AN DAC did better to me than any of those other NOS DACs was in micro and macro dynamics. In fact until I got it (I built it almost two years ago now) I had started to conclude that NOS, while being smooth, sounded a bit flat and lifeless. That's not the case with the AN DAC *at all*. (For example, it has thunderous and very dynamic bass, possibly partly related to the very low Z of the transformer-coupled output.)

Do you find that your Oppo player makes horns sound properly full and harmonically complete? What's the rest of your system? I see you have AN/E speakers - which are certainly great and definitely have truthful timbre.

I wouldn't think the differences in timbre & tone would be subtle, but color me confused. Your system sounds top-notch - just the kind of gear I like - and I'm sure you can hear.

I would certainly try replacing all the tubes. In fact my DAC is probably due for a new set too. Good thing they're all cheap.

Please let us know at some point if it was the dampers or the tubes!

(I'm curious about a design that would seem to rely on undamped tube resonance for positive qualities...)

David,

For kicks today I played an SACD through my Oppo BDP-83. As I recall, it's really, really good! Except for one thing: the machine's output level is so low I don't have enough system gain.

On RBCD it's no match for the DAC but SACD is good.

Epilogue: My player is not an SE, but a "normal" BDP-83.

I didn't notice this difference before. So, really I have no idea what the OP was hearing on his player. Or little idea.

I bet a modded Oppo SE can get quite good then.

The stock one is still chock full of mediocre parts (at to anyone who considers all opamps sub-par).

(The Sony 5400 is the same; opamps, so-so-parts at best everywhere, sounds great stock.)