Current or Previous Harbeth Owners…

If I may add. Agree with other comments about stands. The Ton Tragers are without a doubt the best match with Harbeths. They make quite a difference because they allow full resonance of the cabinets. They make the Harbeths sing. Worth the investment if you are a Harbeth owner. 

Spendor or Graham. I like both better than the Harbeths. The Graham 5/8 is probably the best of the three to my ears. 

IMHO, there are brands that employ more advanced materials/tech that sound better than any of the thin-wall, BBC derivatives. Some of those are Rockport, Acora, Borresen and Joseph Audio. 
 

Just like dpac996 I have chosen ATC after several smaller models of Harbeth. ATC does have a better, more colourful midrange and the dynamics are much better. I’m a classical listener and Harbeth is an often advised brand to people like me, for some years now I have felt no need to change my speakers, other equipment yes.  

I’m a member of a large audio club and we have a Zoom social weekly. There are a lot of very experienced, even obsessive, audiophiles in attendance. I attended the usual weekly Zoom meeting just two weeks ago and came away with what I think is valuable advice on a speaker that you might consider listening to. Here’s the story I heard: a fellow audiophile member had some Danish speakers in for review which he liked very much. When he had finished his review and returned the speakers he was instantly aware that his Harbeth* speakers sounded dull and unmusical in comparison. The difference was so obvious that he immediately decided he had to sell his Harbeths and buy the Danish speakers, which he did. He is very happy with the change and kept emphasizing how much more musical the Danish speakers were. And, interestingly, the Danish speakers cost about half what the Harbeth’s cost. Perhaps that’s because the Danish speakers are sold direct unlike Harbeth speakers which are sold through distributors and audio shops which raises their cost to the consumer. It also turns out that Harbeth speakers are built to a price point and contain el cheapo parts in their crossovers; the Danish speakers have an opposite philosophy in that their speakers are designed with the best parts that will perfect the way they sound. Also the Danish speakers are shipped free all over the world and have a 60 day trial period.

The speakers are Buchardt S400 MKII. They are perfectly suited to his smallish room. I don’t know more.

https://buchardtaudio.com/collections/passive-speakers/products/s400-mkii-color-se?variant=48341062025562

* I’m not absolutely certain of the model no of his Harbeth speakers I think they were 30.2s. They might have been 40.2s.

Let me add my voice to the chorus of high praise for the C7ES3. I originally chose that model because more than one Harbeth employee mentioned off the the record that upper management considered the C7 line the "best-sounding" of what Harbeth had to offer (whatever "best-sounding" means -- I can’t get into that here, but regardless, that was a convincing endorsement).

I’ve had my pair for, I dunno, 10 years?, and in that time, upgraded from a sub-$1K amp to a $19K T+A. In every case, yes, in terms of voicing and cohesiveness, these little boxes rivaled the Quad ESL (57s) that I’d restored & enjoyed for over 20 years. I’m sure that many people have other favorites in this price range, but overall, these non-flashy little speakers are stunningly lifelike in many ways -- at least in my 14x17 room, paired with a sub.

Having said all that, they’re not perfect. They throw a decent soundstage, but don’t disappear as well as some of the competition. Despite their generally excellent imaging, I can always point to the speakers with my eyes closed. However, given all the other strengths of the Harbeth house sound, that’s never been a showstopper for me. they still regularly provide a thrilling listening experience with content like SACD or 45RPM vinyl.

These comments only speak to the C7 stand-mount models, which are the only ones I have extensive personal experience with. But my understanding is that the main ways in which the larger and smaller models differ is in bass extension and dynamic range (and, to a minor extent, to treble extension).  All Harbeths are reputed to have similar house sound.

As for the thin-wall-construction controversy, all I can say is that it seems to work. Aside from the fact that it’s nice to have 15-pound speakers that produce this level of SQ, I did personally confirm that part of the BBC’s design philosophy was to not even try to eliminate all cabinet resonances -- but to instead minimize them and then incorporate any residual resonances into the speaker’s sonic signature. That is, the overall system design expects the cabinet resonances to exist and is tuned to complement them.

I verified this by damping the cabinets externally, just out of curiousity. And when I did so, the sound degraded considerably, lifeless, dull, colored. I guess that’s one reason why Harbeth recommends minimizing coupling with even the Harbeth-recommended Sound Anchor stands.

Bottom line for me is that the Harbeth line -- especially the C7ES3 -- are undoubtedly worth considering in their respective price ranges. Not for everybody, not for every system, but still an extraordinary box speaker in its price range.  Add a top-notch sub like a Perlisten, and you’ll have a heckuva good $5-10K system for a small or mid-sized room.