Thanks to recent posts, all very interesting. Here are some comments:
Space is at a premium for me, both in my equipment rack as well as in the room itself. @jji666, I pace all day waiting for my turn, hoping the wife finishes work early. Hardly ideal but it is my lot. Nowhere else for headphones...
@jimpainter, I am coming to see the Marantz may be a weak link, which makes me heartsick considering it was purportedly of audiophile quality for 2 channel, not to mention its cost. It certainly works well in the HT, but audiophile quality is in the ear of the beholder. I would love nothing more than to invest in more "stuff," but my loving wife has no patience with nor understanding of the equipment merry go round that this hobby is. A good preamp may be the price of admission to quality 2 channel audio, but then there is the inevitable follow up of replacing the humble Node and my Gustard DAC. A combo unit also makes sense. A couple thousand here, a couple thousand there, and I am into some $$$ for something that is lesser for me. Yet...
During this last week I had many conversations with Juan of Bliss Hifi, who is experienced and well-versed in this arena, patient and generous with his time. He echoed the sentiment here about a quality preamp, and made suggestions that fit my situation and mindset of the moment.
I just received a T+A DAC 8 DSD on approval basis. It is an oldie but very goodie. Not the current model, to be sure, but within the budget and consistent with the level of my equipment. It is a very solid step up in sound quality from my Gustard, and displays a sophistication that my system lacked, showing me what digital music can be with quality components. Rather than taking a measured approach, I decided to do most of it now and leapt into this with both feet; an Aurender N150 arrives in a few days. I will add the Aurender to my current system and see what it alone offers, then throw the T+A into the mix. Yes, my HT preamp might still be a choke point, but the new equipment will hopefully get me closer to where I would like. @jji666, the Parasound is a good choice as it has a slim profile, which makes it easier to place. If all goes well, that or perhaps a used BHK (thanks, Juan) could be a follow-up step. We shall see how this first phase of the transformation goes.