Bruce (Bifwynne), I wouldn't consider the use of a Jensen transformer to be a jury rig/jerry rig/kludge (whichever terminology one prefers). It's a legitimate means of converting a single-ended signal to a true balanced signal pair.
Consider also that some extremely highly regarded preamps have transformer-coupled outputs, and in some cases also utilize transformer coupling in their internal signal paths. Examples include the Coincident Statement line stage, and some ultra-expensive Audio Note models.
Of course, all transformers are not created equal. But the Jensen transformers are well regarded, and as I've indicated multiple times in this thread, a number of highly experienced members here who have very high quality systems have reported excellent results with it. And the OP was quite happy with the results he was getting with it, until an unrelated problem he experienced caused the thread to be resurrected, and various subsequent responses unrelated to that problem caused him to become concerned about theoretical issues that may or may not be subjectively significant, or even perceptible, in his system.
Regarding your other comment, I don't doubt that for some and perhaps many listeners the Ref 150's power capability may be marginal with the Maggie 3.7, and in fact that very issue is being discussed in
another current thread you are participating in. Of course, the degree to which that may be a concern will depend on the particular listener's preferred volume levels, on the dynamic range of the recordings that are listened to (well recorded minimally compressed classical symphonic music perhaps being the worst case), and on listening distance and room size.
My impression, however (derived in part from your comments in other threads), is that the power supply of the Ref 150 is robustly designed, including large amounts of energy storage. Which, together with your comments about its marginality with the particular speakers, reinforces the concern I expressed in my previous post about the adequacy of the lower power rating (100 watts) of the CAT JL5.
Onhwy61, I'm surprised at your response to what I thought was a knowledgeable and entirely appropriate input from Knghifi. I would especially not have expected such a response from you in particular.
Best regards,
-- Al