The Marantz SA-10 has two USB inputs but they cannot be used for streaming and both are synchronus. One is a USB -A used strictly for stored music and the other is USB-B which is dedicated to iPod input, and older versions at that. The SA-10 is unfortunately dated in this USB respect although from what I read unless a DAC is uber expensive most of the streamers sound better through COAX. I think the method of streaming USB vs. COAX also has something to do with the clocks in both units and which one dominates in each of the two methods, but I'm not sure. I know the Marantz has two femto streamers and the ifi has one. The SA-10 does have an optical streamer input but the ifi Zen Stream does not have an optical output. Just because the SA-10 manual is a little confusing, I connected the ifi Zen Stream via both USB inputs and got nothing. Anyway, my goal in getting the SA-10 was to make sure I had a high end SACD player and I liked the idea that, like the PS Audio Direct Stream, which went out of production at the time because it used a Toshiba disc drive, of converting and upscaling everything to DSD. The fact that the SA-10 allowed streaming at all I considered a bonus if I were to try streaming. My first attempt was to use a usb cable from my Macbook Air laptop and be able to sit across the room so I invested in a long usb cable and thought the sound was decent, but not good. The next goal was to try a dedicated streamer at a minimal investment so I found a new ifi Zen Stream for $275 and that sounded good. Then, of course I had to read more and found linear power supplies make a difference so for a few hundred bucks got the ifi version from Amazon. No question the sound improved. I made sure I had a true 75 ohm SPIDF cable. My goal in all of this was to use the setup to preview music and then if I really, really like it, buy it on disc. Now, however, I found the streaming setup sounds really good, even on free Spotify with its low bit rate lossy transmission. No doubt the "Dac-less dac" in the SA-10 with its proprietary Marantz MMM conversion and DSD output has something to do with that. I'm guessing for the investment what I'm getting is pretty close to optimal free Spotify sound. So those goals have been achieved. Now, the next step is to do some more critical listening as best as I am equipped) to compare cd and the streaming setup and then see what changes with Quobuz. I don't buy that many CD's or SACD's anymore so I can then consider a Quobuz subscription to break the disc habit. Whether it pays for me to take a next step to another DAC or streamer or combination might be questionable at that point and the investment spectrum is wide open. I am intrigued with the new Eversolo DMP-8 because at its price point it would enable me to compare the AKM chip dac sound to the Marantz. Plus if I can figure out the connections the Luxman has two sets of balanced inputs. One would be used for the current setup with the Eversolo streaming through the Marantz DAC and the other can connect to the Eversolo DMP-A8's balanced inputs. The Luxman then with its front selector dial lets either of its balanced inputs be used as an integrated amp or just as a power amp. So the Eversolo could then be used with the Luxman power amp. The Marantz SA-10 also has digital outputs and the Eversolo DMP-A8 has digital inputs so the system can be connected that way, too. There are so many ways to see what sounds like what I think it would be very interesting.