I have not heard either of these players but auditioned the SA-10 and D05u together, and owned the SA-10 and D08u. Since you said you have been reading up on them, you are probably aware of all of their features but I'll mention a few that would be important to me:1) Marantz plays SACD and not MQA; Luxman plays MQA and not SACD. I own a lot of SACDs so the Luxman would be out for me. If you have Tidal, the Luxman will probably be a winner - I used to use a Lumin to stream MQA and thought MQA was really nice.2) Luxman has XLR out and Marantz only single ended.3) Marantz upsamples everything to DSD. This is something that you don't see mentioned a lot.
I think the ruby is a heck of a deal money-wise; it seems to be basically a SA-10 without being balanced. Sound-wise, I ultimately chose Luxman over Marantz because I did not like that Marantz upsampled everything. I found on some CDs the Marantz seemed to cut off some high frequency info (in fact, you'll see info here from other users like Elizabeth on the SA-10 thread that talks about picking the SA-10 specifically because it is 'not hard' in the treble - may be a good thing for some depending on the overall system. It definitely is very smooth). I have had other digital solutions that when upsampling to DSD it did the same thing. I like the flexibility to play everything in its native format. If you are using a streamer or software that upsamples you can send it to the DAC/CD player in the format you want anyway. So the marantz takes that option away. Both are excellent, but overall I also preferred the Luxman house sound, which seems to be slightly more detailed than the Marantz; a little more sparkle on top perhaps, very transparent but still a bit warm. I want to hear the flaws in CDs if they are there. Since I have not heard the D03 I can't say exactly what it sounds like but I would be surprised if it did not retain the Luxman 'house sound.' If you can get a Marantz at $3k and don't care about MQA or balanced outputs, I think that would be a great CD player and deal if paying retail for the Luxman. When I auditioned the two other units together as previous mentioned, I used SACDs only and we flipped back and forth between the two simultaneously on a preamp using two identical SACDs. I honestly could not hear a difference between them. That is why I initially purchased the Marantz because the dealer gave me a good deal on it as compared to the Luxman. It was only after I got it home I noticed I did not like its top end lack of detail with CDs/redbook. On SACD it is really good...again, probably because it is a DSD machine (literally and figuratively!). The Marantz is a very musical player. Overall, you probably can't go wrong with either. If it was just about sound, if I had a somewhat dark system I would probably choose the Luxman; if the system was a little bright the Marantz might be the best choice. At $3k Marantz and Denon also just came out with an anniversary model that might be worth checking out.
I think the ruby is a heck of a deal money-wise; it seems to be basically a SA-10 without being balanced. Sound-wise, I ultimately chose Luxman over Marantz because I did not like that Marantz upsampled everything. I found on some CDs the Marantz seemed to cut off some high frequency info (in fact, you'll see info here from other users like Elizabeth on the SA-10 thread that talks about picking the SA-10 specifically because it is 'not hard' in the treble - may be a good thing for some depending on the overall system. It definitely is very smooth). I have had other digital solutions that when upsampling to DSD it did the same thing. I like the flexibility to play everything in its native format. If you are using a streamer or software that upsamples you can send it to the DAC/CD player in the format you want anyway. So the marantz takes that option away. Both are excellent, but overall I also preferred the Luxman house sound, which seems to be slightly more detailed than the Marantz; a little more sparkle on top perhaps, very transparent but still a bit warm. I want to hear the flaws in CDs if they are there. Since I have not heard the D03 I can't say exactly what it sounds like but I would be surprised if it did not retain the Luxman 'house sound.' If you can get a Marantz at $3k and don't care about MQA or balanced outputs, I think that would be a great CD player and deal if paying retail for the Luxman. When I auditioned the two other units together as previous mentioned, I used SACDs only and we flipped back and forth between the two simultaneously on a preamp using two identical SACDs. I honestly could not hear a difference between them. That is why I initially purchased the Marantz because the dealer gave me a good deal on it as compared to the Luxman. It was only after I got it home I noticed I did not like its top end lack of detail with CDs/redbook. On SACD it is really good...again, probably because it is a DSD machine (literally and figuratively!). The Marantz is a very musical player. Overall, you probably can't go wrong with either. If it was just about sound, if I had a somewhat dark system I would probably choose the Luxman; if the system was a little bright the Marantz might be the best choice. At $3k Marantz and Denon also just came out with an anniversary model that might be worth checking out.
