Shunyata Venom RCA vs Bluesound Node 2i stock rca

Are you sure you heard a difference? Did you do some blind trials? Sighted listening does not count because seeing the object under test leads to biased judgements.

I wouldn’t worry too much about the RCA interconnects at this point. I think you’d get more out getting a new DAC, a linear power supply for the Node, and using a Wi-Fi extender or Mesh system so you can run an Ethernet cable from that to the Node. Each one of these will probably yield nice improvements, and they’d be additive as you implement more of them.
 

I’ll just add that you’re using older midFi components including an AVR that will limit the extent to which you’ll hear the benefits of the above upgrades.  Personally I wouldn’t throw too much $$$ into this and would focus rather on upgrading your components if you’re really looking for better sound.  Otherwise, just sit back and enjoy what you have.  Just my $0.02 FWIW.

I think you gotta live with it in the system for a while. You might hear a difference with a quick A - B comparison but it would be very logical for that to be affected by your expectation that you will hear a difference, just like @jasonbourne71 mentioned, and seeking/paying attention for what stands out. That can be very subjective and in my experience results might switch on you.

In my experience there’s little doubt that the interconnects can make a big difference, but whether it is an improvement or just a change in the frequency response in some part of the range can be a challenge to determine.

@jasonbourne71 I have a question for you - not trying to start an argument - have you ever tried swapping any wires in your system? I’m curious what you’re using and how you arrived at your setup. I was a cable agnostic until an unexpected encounter plainly demonstrated a difference between my standard interconnects and another pair. I was irritated to find that power cords made a difference, a power conditioner made a difference, interconnects and speaker wires. I am glad I had this experience, as my system sounds much better than it ever did before. I kind of kick myself that I spent so many years listening to wires that were negatively impacting the sound of my system.

I kind of kick myself that I spent so many years listening to wires that were negatively impacting the sound of my system.

@markusthenaimnut  Nah.  Pat yourself on the back and Goodonya for keeping an open mind and having the confidence and courage to trust your own ears.  Many here never manage that and they need to have numbers or experiments tell them what can sound good and rather waste their time telling those of us who clearly hear differences that we’re just kidding ourselves.  Obviously you now know different and are reaping the significant and ongoing benefits of your efforts. 

I wouldn’t bother with cables for that system. Not yet at least.
Better and more transparent cables will just highlight some of the drawbacks up and down stream. BluJeans cables should be fine. 
If your Denon amp works good, look into upgrading speakers.