Transport & tweaks for audio logic 24MXL

I just bought an audio logic 24 MXL with Marigo apparition digital rca and it sounds good with stock denon 3910.

Would i improve performance significantly with better transport? I want to stay below $ 1000 used unless there is huge gain. How is CEC TL51Z?

Are there tweaks with power cords or NOS tubes?

Thanks in advance
Depends on your definition of "significantly"; there will certainly be a difference. Summarizing the past threads (and you should check the archives) the CEC TL-1 and 2 and the Forsell (which I use) are favored transports with the Audio Logic. I'd hold off on tube rolling till you get used to the stock tubes, but I have used Siemens E188CCs and Ccas, and Telefunken Ccas, with very good results. Best power cord I've used with my Audio Logic has been the Kubala Sosna Emotion; for significantly less the K-Works Empowered Cord and Dynamo power cords and TG SLVRs are excellent as well.
Rcprince's advice is spot on. As a long time AL owner, listen to his thoughts carefully. I am among the crowd of AL owners who have an earlier model, in my case the M34DSB. I use a CEC TL2 and the combination works very well. If you search the threads you will find many who are using the CEC/AL combination. The only thing I would add (which has been in prior threads) is that this DAC responds VERY well to good air isolation. I use a Townshend Seismic Sink and I believe that Rcprince is still using a K-works. IMO, air isolation under this DAC improves any tube that you will use.
The first thing you should do, since this is a stock transport, is buy a 1.5m digital cable. This white-paper I wrote explains why:

Steve N.
Empirical Audio
You could change the capacitors to Auricaps. Symposium makes special mini pads that go under the caps for isolation which is something that i'm looking into.
As stated above by Rcprince & Jeffcott :

I run a TL-2X into a Virt. Dynamics Master Bal. to a A.L. M-34-DSM with NOS tubes.

A King Cobra V-1 on each handles the AC.
also try to play around with the rca vs xlr analog outs if yours has both- I ordered my 24MXL has the optional $$ XLR outs, assuming it would be the superior interface to the preamp, only to discover (and this was confirmed in a friend's reference system) that the single-ended outs sounded more involving and musical to our ears- YRMV...
The simple answer is yes you will definitely improve sound with better transport. The question is which one is better to your taste. Very often there are no simple better or worse but just different characteristics and you have to choose which one you like better. I'm not commenting on Denon v CES cause I never heard either one, but hypothetically, better transport will obviously result in better sound. Will it be a huge change or marginal, it is up to you to decide. To me the difference between Sony7700 (stock)and 10 years old Krell 20t (stock)is big - Krell is much better sounding unit, but I'm sure that some people probably would say there is no difference at all or that difference is not worth the money. To make a long short, you should not rely on somebody’s taste but get both components at the same time in to your system decide which one you like better, and even then it won't be an easy task. :)
Thanks a lot guys. I tried the DAC with $70 philips dvd player, denon 3910 & modwright 999es. They all sound different with the 999 producing the best result.

I just got a new TL51X today and it bettered all the other transport. More details, weighty and full and improved spatial clues. One thing i did not expect was the improvement in macrodynamics. I thought i was going to get the Apl 3910 but i am pretty happy with the sound. may be I am done for now.

What are your favourite NOS tubes with the audio logic?
Rcprince's experience with tubes from his use in the previous response are all good recommendations and are all in the upper crust of the 6922 tube family. There are a wide selection of tubes in this family, spanning from "modest and affordable" to really expensive. You might find it helpful to try a small selection of "affordable" choices to get a taste of the changes you will find in your system. In addition to Siemens and Telefunken, you might want to look closely at the Ameperex family: there are a lot of choices. I have had very good success with carefully selected Brimar ECC88's.
Thanks guys. I got a pair of Holland Amperex 5922 and they are a worthwhile upgrade. The Purist audio Dominus is also superb.
btw- for digital cables w the 24MXL, I can't recommend the Marigo Labs 5.7 Sig highly enough...
What did the Amperex do for you?
Thanks, Sutts. I also have the marigo apparition. I have the version with metal jacket. Do you know what version is that? is the newest version much better?

I got the Holland Amperex 6922 PQ. It has lower noise level and more details than my original tubes (unknown NOS by previous owner). I used used to run RCA input. With the PAD Dominus XLR and Amperex, the detail and front to back imaging is better. THere is more composure on complex and loud orchestral music.
interesting Glai- I don't have that option, as my Vecteur transport offers rca digital out only, no XLR- thanks for the feedback on that though.