Do powercords make a difference in sound?

Zaikesman -- I suspect that you would have been thorough enough to do this, but just to be sure, did you repeat your power cord comparisons after you obtained the footers, to verify that similar differences resulted with the various power cords you used when the unit was right side up, compared to when it was upside down?

Obviously the preamp was not designed, developed, tested, and voiced with the expectation that it would be used in an upside down position. I can certainly envision that operating a component upside down would have sonic consequences, due to the thermal differences that would result throughout its circuitry, those effects conceivably including increased sensitivity to variations in power-related parameters such as ac voltage.

Regards,
-- Al

Hi Al, if there was any sonic difference between having the preamp right-side-up and upside-down, I was never aware of it. (As best I remember, I tried listening for such when I first turned it over, but not with the expectation of hearing much if anything different.) I did, however, eventually change the power cord again, from the model I had chosen over the stock cord at the time I reinstalled it right-side-up, to another model I use today throughout my system, and those comparisons were carried out in normal orientation using the adapter. (I should note that some other aspects of my system had also changed during that time span, and still more since.)

As a postscript, I also remember talking again to the ML dealer and mentioning my findings. I thought I was enlightening him, based on what he'd told me, but his reaction was that he wasn't surprised, that of course if you upgrade the power cord on any component you're likely to hear some improvement in a revealing system no matter how good that component's power supply, but getting into that just wasn't practical for his ML preamp customers. (I'd also note that the No.38x series was designed prior to the time when aftermarket power cords came on the scene, and I do believe that ML's later preamp offerings dropped the obscure receptacle placement.)

PPS - Hi Richard, almost as soon as I'd posted I wished I hadn't taken the bait, so thanks!

I would like to think I have designed a few during my career.

Dear Mr. Liguy: I would like to think a lot of things about myself (and a few of them may even be true!), but in the situation I had something of particular relevance to tell you, I'd go ahead and spell it out...

I am truly sorry but I simply do not subscribe to your accessment. I mean no offense. I am sticking to my guns that properly designed power supplies do not require fancy power cords. I do not disrespect your opinion, I simply do not hold the same opinion. I have designed power supplies for a living and fully believe that I, during my career, have designed more than a few that can allieviate the effects that would cause detriment to audio reproduction.
I mean no ill will, we simply disagree.