Changed the power cord to SignalCable Magic Power cord on my CroMag II

I changed the stock power cord on my Cronus Magnum II today to the SignalCable Magic Power cord and the results left me speechless. I can’t believe the difference it makes to the sound quality. It just opened up everything...the highs and lows. The soundstage is so much better's like I’m listening to a different amp. One of the CDs that I always test with, Eric Clapton unplugged sounds amazing. Every change to my system seems to be getting me closer to the sound that I want to hear. Initially, I thought it was the speakers so I upgraded from a decent set of Dynaudio speakers to very good set of Harbeth C7 speakers and the sound improved but not significantly. Changing the power cord was a night and day difference in the sound Can you guys suggestion some other relatively cheap changes to improve the sound? Anybody witness similar realizations?
Welcome! to the "club" nycjlee

Cabling does make a difference, for better or worse, enjoy your new found sound. SignalCable is certainly a sleeper in terms of price and performance.

Happy Listening!
Yes, I have experienced power cable changes that truly rival major component upgrades.  Glad you found one that makes your system sing!
Receptacle and dedicated circuits if you haven't done so already. If you haven't done this you will be amazed again on your new PC.
Many years ago, I upgraded to the Signal Cable power cords on both my Rogue Audio Cronus (original non-Magnum) and my Rotel RCD-1072 deck.  Very similar experience to what you described.  Happy Listening.
My experience with Signal Cable was not as positive.Though I did not use them directly with components but instead used them on my Richard Gray Power Conditioners-two of them- one to link them together and the other into the wall outlet.I really did not notice any sonic improvements and chalked it up as a learning experience.I also bought a Signal Cable for my REL sub high level input and I thought there was a worthwhile improvement in sonics.If you want real sonic improvements you have to come with some more cash-in my opinion. A pair of Shunyata 20 amp chords for my ARC Ref3 and Ref 110 really transformed my system.I was amazed and almost 2 years later I still am.

Richard Gray makes their own 15A and 20A power cords for the conditioners and does not suggest using any other manufacturer's PC.

Richard Gray makes their own 15A and 20A power cords for the conditioners and does not suggest using any other manufacturer's PC.

Of course, of course......
I failed to mention that I have had 3 Richard  Gray High Tension PC's(sold one of them) and now I have two and have used them on all of my equipment. They are being used on my REL Stadium and as a connection between one of my Richard Gray Power Conditioners and the wall outlet. I think they are somewhere between the Shunyata's and the Signal Cables as far as performance goes. This is what my ears hear anyway. The cost of this cable also reflects this.

Synergistic Research (SR) is a sonic match for REL subwoofer.
Otherwise, I have only read on (1) occasion where an owner was using a Black Sands PC on his Richard Gray conditioner ( several years ago).
Sad to report but I had to send the signal cable back after a two weeks.  I initially thought the cable made the system sound better, but I quickly realized that my amp was no longer neutral sounding (this is not what I wanted).  Back to using the stock power cable.  Maybe, I'll try a Pangea power cable at some point. 
I had a signal cable power cord and felt that it made no difference whatsoever versus stock power cords. I'd suggest trying Audio Art Cable power cords, to my ears an obvious and positive impact
Upgraded to an Audio Art cable (1se). It was much more expensive but the sound improvements were neutral and easily heard. I'm happy with the new cable. 
After one week and a couple of different configurations, I've ended up with using the two new MagicPower Signal Cable power cords I recently purchased on my phono preamp and main preamp.  I have Audio Refinement (YBA) separates and when I used the MagicPower cables on my main preamp and amp, my system sounded too warm and lost it's punch.  The current dual preamp config kept the punch and PRAT I'm used to hearing yet expanded the soundstage in a 3D manner with a little more warmth, similar to how great tube preamp / solid state amp combos sound.

I might get two more MagicPower cords for my tuner and oppo 103.  I kept the Volex unshielded power cords on my amp, tuner, oppo and cd recorder for now.

Full system details on my system page.
I know this is a bit old subject but I'm not quite understanding OP's remarks about the affects of power cord. If a component  sounds very neutral by design out of the box, then any aftermarket "upgrade" or tweak with any noticeable impact, will by definition move the sound quality away from being neutral. Otherwise it will have no impact. For me, any tweak worth keeping is there to make a positive change.
@nycjlee As the US Distributor of YBA, we use and HIGHLY recommend the Audio Art "Signature" power cable. In fact, we included the AA Signature AC Cord with the YBA "Passion Pre/DAC" when it was reviewed by "Soundstage Ultra".