Regarding one’s choice of recordings when evaluating FW, Yale is so good that it really deserves good SQ recordings to evaluate as many parameters as possible in the best possible light. If you shine a 15-watt bulb in your room it is hard to see everything clearly. But if you shine a 100-watt bulb in there then lots of things come clear. I think that’s a good analogy.
There are so-so stereo and even mono recordings that I like to listen to with Yale. Regarding the latter, they often serve a special purpose – to evaluate FW for reasons that may have special meaning for us. But Yale really shines when you offer it the best you have. This does not necessarily mean that you need to use the most modern recordings put together in today’s high tech cyber studios. In fact, some of my most favorite reference recordings go back to the 60s and 70’s with occasionally forays even into the 50s. It depends on the mastering. For instance, I have a bootleg DSD Frank Sinatra CD with recordings from the 50s and 60s that is superbly mastered and is excellent for evaluating Yale.
All parameters – detail/definition, tonality/harmonics, dynamics, transients, sound stage, imaging – are much better served up by Yale with well-recorded material. Lesser quality material will not show the improvements rendered by new FW to the same extent. Indeed, It may sometimes be difficult to distinguish one FW iteration from another when using lesser quality material for evaluation. To look at in another way, it may be difficult to say if such-an-such a parameter “moved” much at all with some material.
Another older recording I have talked about on the forum is The Trio at The London House with Oscar Peterson. Norman Granz did a superb job with the London House series. With Yale, the tonality of the piano, the snares and the bass are so well rendered, nearly 55 years after this recording was made. With each new FW upgrade you can easily hear the improvement in SQ on these and other good recordings. Yale is a real pleasure to listen to hours on end. I wonder how much further future FW upgrades will take us? It’s hard to imagine the sound getting much better than this.