"Personal Preferences: I am looking for non-fatiguing, warm, musical qualities. In another discussion topic here on this forum, @mtrot and I agreed about "smooth, sweet, soft, silky treble" and "shimmery, airy cymbals" as goals."
Sorry, but I don't think there are too many people here who'd read this and then recommend a "professional" grade amp. Pro amps are generally made for durability, affordability, and overall power delivery capabilities -- not refinement. Almost the polar opposite of what you're looking for. The reason the 5000 was priced similarly to the 3500 is probably that the 3500 uses a transformer-based power supply and the 5000/7000 use a switching power supply -- probably for cost, efficiency, and weight savings, not sound quality. I think you may be fighting an uphill battle reaching your goals with this amp. I'd dump it and move on to a more synergistic amp/speaker pairing for your specific tastes and goals. Sorry to be the bearer of negative news, and best of luck.
Sorry, but I don't think there are too many people here who'd read this and then recommend a "professional" grade amp. Pro amps are generally made for durability, affordability, and overall power delivery capabilities -- not refinement. Almost the polar opposite of what you're looking for. The reason the 5000 was priced similarly to the 3500 is probably that the 3500 uses a transformer-based power supply and the 5000/7000 use a switching power supply -- probably for cost, efficiency, and weight savings, not sound quality. I think you may be fighting an uphill battle reaching your goals with this amp. I'd dump it and move on to a more synergistic amp/speaker pairing for your specific tastes and goals. Sorry to be the bearer of negative news, and best of luck.