HE-6 = very good with Stratus and super-resolving Sabre DAC.
HE-6 = even better with SS speaker amp and NOS tube DAC.
HE-5 = best with Stratus and either DAC...
I agree - keep tubes in the chain!
My $.02
This old saw, well... To me it depends a lot on what "noticeable" means and whose ears are doing the noticing. Plus please keep in mind it's not just the conductor that matters, the construction of the cable matters MUCH more. People compare copper to silver and after-market to stock using cables that have the same incorrect geometry, the same smearing dielectrics, the same detail-crushing connectors, and then they wonder why they can't hear very much of a difference. To be sure, silver is generally faster and more liquid but tone can falter while copper puts meat back on the bone sometimes at the expense of detail. I prefer a combination of both and that's what SAA has, actually. But the construction of the cable is where you will *notice* incredible differences. By eliminating teflon and bogus shielding technologies and expensive multi-metal connectors you will achieve quite an obvious upgrade in sound. Less is more. This also partly answers the question about connector type. From my experience, the 4-pin XLR sounds best - including in the Stratus - of all connectors - with the 1/8" next (which for the Stratus is moot, I realize.). For me, these changes have made it impossible for me to ever go back to any kind of stock or stock-made cable.
That's one of the advantages to the TRS input on the Stratus, the options between the IEC/Low impedance and 0db/-6dB gain allow you to tailor the sound much more than the switch between SE and BAL on the balanced intputs. For that reason alone sticking with a 1/4" connector might be a good idea...
