Marantz SA-10 Vs Esoteric K-05Xs

Here is what the K-03XS manual says about upsampling:

Upconversion setting UPC>***

This setting can be made for each input.

During Super Audio CD playback, the DSD signal is sent as is to the D/A converter without being upconverted.

ORG - (original) The input signal is sent as is to the D/A converter without being upconverted.

2Fs - 32kHz, 44.1kHz and 48kHz sources are upconverted to double values of 64 kHz, 88.2 kHz and 96 kHz, respectively, and then sent to the D/A converter.

4Fs - 32kHz, 44.1kHz, 48kHz, 88.2kHz and 96kHz sources are upconverted to double or quadruple values of 128 kHz, 176.4 kHz or 192 kHz and then sent to the D/A converter.

8Fs - 32kHz, 44.1kHz, 48kHz, 88.2kHz, 96kHz, 176.4kHz and 192kHz sources are upconverted to double, quadruple or octuple values of 256 kHz, 352.8 kHz or 384 kHz and then sent to the D/A converter.

16Fs - 32kHz, 44.1kHz, 48kHz, 88.2kHz, 96kHz, 176.4kHz, 192kHz, 352.8kHz and 384kHz sources are upconverted 16, 8, 4 or 2 times to 512 kHz, 705.6 kHz or 768 kHz and then sent to the D/A converter.

DSD - The signal is converted to DSD digital format, and then sent to the D/A converter

So it appears you can not upsample at all, or you can upsample from 2X all the way up to 16X or DSD for each output.

@fauguy , Yes the upconversion settings do apply to CDs and I would guess, but the manual doesn't say it, they would apply to streamed PCM also.  There appears to be only one digital filter.

I agree with @goose, these are probably not settings that you will change a lot.  You'll probably find one setting you like and leave it, if you can hear much of a difference at all.

Really the way to decide between the players is to listen to them and buy the one you like best.

I understand @fauguy , my situation is much worse than yours. I’d go listen even if they don’t have the models you’re interested in. My guess is that the two brands have a different house sound and that you would prefer one over the other. 

That the room and equipment that you listen to at a dealer are very different from what you have at home doesn't help either.