Shaunp
I think what I said was the mids could be recessed or made more prominate (marginally so, yet noticeable) by playing with the imp sw. Not louder or softer, although it might appear that way to some.
... and yes, other aspects of the sound do change too by moving that sw about. it was an eye opener playing with that sw. Teaching me the importance of properly matched and improprerly matched cabling, and what it can do to the sound, if the imp is not right or even close.
AS the Tech alluded too, those numbers aren't 'live or die' figures... given he pointed you to another settings. Their Spectral gear likley does very well on the lower pos.
I did post a review of some ICs, look there for more info as I simply can't recall exactly.
I've had mine set to where I like it so long now I don't recall exactly what all is affected and how, but those results are at your fingertips now, so do investigate.
it'll get more complicated when or if you go to XLR. They have two switches.
I sold my Magnums and now have Shotgun S2s. I use them off my rec into my tube pre for the rec's tuner and cable box radio stations, till I can find another pr. that suits me better. I would like to have again a magnum 1 or maybe a 2, albeit, not to supplant the S2, but to use elsewhere.
More playing time will show you still more resolution, and that buttery smoothness might fade some and morph into a bit more dazzle. it's probably due to the connections within the MIT cabling, as there are more in them than in most other cables.... and there's those components too. that all adds up to lengthier run in or re-run in times. or such is my exp.
Some say around here, simply leaving the upstream item on and the downstream item off, can aid the run in some. Not sure if that is applicable to MIT though... and my exp doing just that shows the effect as quite marginal at best There's no replacement for conducting a signal. IMO
In the end, that switch needs be where YOU need it to be in your system for your preffs. it's your dime, so you make that call. period.
Lastly, as imp varies, maybe this will show you more on that mechanism's worth. Say you add or mix a SE preamp, with a Balanced amp. Now what? The amps input imp is shown to be 50K. usually that means 50K total using XLR cables or both legs of the XLR interface. Or 25K per leg as RCA.
My exp says, it's either one of the two closest to the rated downstream input imp. the mid point usually is the one size fits all, selection... with some exceptions, and why the tech said use it.