Weak Link in chain as I upgrade from mid-fi?

The weak links as I see them—and this is relatively, as you have a decent system-are:

1) The lack of low end extension with your speakers.  As you increase the bottom end you will start hearing things that you had no idea were there previously, low end information that fill out the soundstage..  I can’t address which sub is “best” for SF but REL subs are very musical.  I would check their lineup.

2). I am not a fan of Arcam house sound.  To me it is slick and soulless, kind of cool.  I would ditch it for another integrated minus the DAC.  I would then opt for the best DAC the budget (did you ever specify one?) will allow, as it is the heart of a digital system.

  I am not crazy about the transport you have, but the other two issues take priority.

Xander,

You should consider another path  no one has mentioned yet, which is the array integrated or partially integrated systems. I am talking about the KEF integrated speakers such as LSX for the new LS 60. There is also highly acclaimed  Kii three system and an array of powered monitors out there such as the Genelec monitors. There are lots of good arguments about why these systems offer synergy not possible with separate boxes. Some reviewers that I respect have suggested that if their business was not reviewing individual pieces of equipment they would be very happy with an integrated system so they could stop focusing on Equipment and just enjoy the music. Integrated systems also are a big plus in small listening area because of the obvious space-saving. The last thing I will mention that you might want to be on the lookout for quality digital signal processing that can be added into your system. It helps compensate for the room and can make a bigger difference then the marginal upgrades in things.

Those speakers are very nice, but BOOKSHELF, inefficient and frequency limited.

The most improvement you can make is to replace them with full range. I prefer no vents, if vented front facing like your existing ones are.

Efficient, so you can drive them with lower wattage, lets you use smaller amp which saves money, less heat, more placement options, especially if remote sensor involved.

IF you try subs, agree with soix, TWO, a stereo pair, front facing, adjacent to your mains. Bass, fundamentals and their overtones are/become directional, a wonderful part of imaging.

Just saw this review of the new Gustard R26 DAC and think it should be very high on your list of potential upgrade options.  I trust this reviewer’s ears as his take on my Musician Pegasus DAC very closely mirrors my own impressions, so when he says the R26 performs very near the level of the incredible and much pricier Denafrips Terminator Plus this comes across to me as a no-brainer level recommendation.  Heck, buy it on Amazon and return it if it doesn’t just blow you away, but that seems highly unlikely.  While I’m very happy with my Musician Pegasus, if I was doing it over that is absolutely what I’d do.  But, I still think as good as the R26 may be and as per my prior post, adding a couple good subs will make the most significant improvement to your system and your enjoyment of it on an absolute basis.  Once again, FWIW. 

https://soundnews.net/sources/dacs/a-new-point-of-reference-gustard-r26-discrete-r-2r-ladder-dac-review/

For a small to medium room the Sonetto 1 is fine. I would have popped for the Sonetto II but that is me. I prefer a hi quality 2 way like the Sonner or QLN over floor standers. I have small REL T Zero’s to fill out the lower registers and have tuned them to my treated, small listening space.