Marantz PM Ki Ruby vs Musical Fidelity M6si

@p3ga thanks for the detailed review. Funny enough, I have a very similar setup. I use the node 2i for streaming but is hooked to a marantz sa8005. I bypass the node dac and what a pleasant difference it has made. Everything is so much more musical and non fatiguing.
I’m fairly clear about the ruby but I’m also getting a decent deal on the PM 10 (still considerably more expensive than the ruby).
Have you had the chance to try the pm 10 by any chance? Is it worth the extra dough or should I stick with Ken’s last work of art with marantz ?

I did not try the PM-10; at the time I was looking, I could not justify it at full tariff, so it never entered the thought process. I'm confident that it offers some advantages over the Ruby integrated, especially at the price delta between the two. I might, however, need to spend a retirement-postponing amount on speakers & peripherals to appreciate the difference between the two.

I hope you have the opportunity to try both and would be interested in your findings. 

@p3ga  guess what.. I got the Pm ki ruby. Arrived yesterday and I have spent a few hours with it.

initial impressions, nothing ( and I mean literally nothing) sounds harsh at even very high volumes. Treble is definitely rolled off but there’s still plenty of detail. Mid range and bass are excellent. Vocals are gorgeous and bass is tight and fast. With the musical fidelity 5si, often times I couldn’t go past a certain point with a lot of tracks before it got bright and fatiguing. Don’t take me wrong, MF is a fantastic amplifier, I was considering going for his bigger brother 6si. Very lively and energetic sound. Very musical too. Was a bit too revealing for my dalis esp when playing tracks with a wide dynamic range.

Anyway, the negative seems to be the flip side of the pro. Everything sounds a bit darker and sometimes unexciting.  It’s too early to come to any conclusion but these are just my initial impressions.  Does this make sense?

what changes do you think I should expect as it burns in?  
Thanks again for helping me pick this amazing and unfortunately, underrated amp. I’m elated even with the way it is right now.

I am done looking for perfect measurements and clinical sound. I just want engaging music and the PM ruby shines on that front. Great work by KI!

Well congratulations on the new addition to the family!

There was some break-in time, I recall more extension in bass & highs after a few weeks. 
In one of the posts above, nonoise mentions power conditioning: I can attest to the fact that the Marantz likes & appreciates clean power.The amp is revealing enough that you should be able to hear a difference in ac cables: A Pangea will make the amp sound dull and lifeless; the Amazon iron lung jellyfish  (<$20) really opened up my system:
https://www.amazon.com/CableWholesale-10W2-51506-Green-6-Feet-Hospital/dp/B0069FLXLU
There's hundreds of others, I stopped there as I'm satisfied. For now :)

FWIW, I am using the Canare 4s11 speaker wire & Audio Envy interconnects from the Ruby SACD. An Audioquest Powerquest 3 protects all from voltage irregularities. Happy camper here.

Hope you enjoy the amplfier as much as I have mine.

@p3ga funny coz I just ordered the canare 4311 after a lot of research, and turns out it’s your recommendation.

I’m absolutely loving the amplifier. It’s opening up nicely, I can already hear a great deal of difference. Highs and mids are opening up and bass is punchier too.

That $20 power cable really make such a big difference? It’s so cheap that I cannot not try.

different topic, do speakers on spikes sound better than those on rubber feet? I have my Dalis on herbie’s rubber feet coz I have wooden floor. I’m wondering if I should buy those spike feet if they’ll make them sound better. Any thoughts?