People That Have Upgraded From Harbeth 30.1s....

Sorry for the RANT! No coffee and I love the sound of my Harbeth's! Guess I should dial back the passion.....

@mountainsong 
i have the C7es3 and love them but at times their warmth is too much of a good thing.  
are the 30.1 s more neutral and dynamic?  less  enclosure warmth ?   thank you.  

avanti,

From my auditioning the 30.1s are more even and controlled through their frequency range. 


When I auditioned the 30s I really liked their sound, but wished for some deeper bass.   The C7es3 did that and I liked it for the bigger sound, but found the bass to be a bit overwarm and less tight than I'd like.

That's why I ended up owning (for a while) the Super HL5Plus which were for me the perfect version - bigger and more full than the 30s, but also the best controlled and most balanced bass of the line (not to mention, more realistically open and extended on the top end, without losing the Harbeth midrange magic).

The sound of 30.1 is just more refined. It handles delicate things better. Bass is less but it is punchy. The 30.1 tweeter is a tough to beat. I'm considering trying at home a set of Raidho C1.1s that my dealer has.

This was my experience too. The m30.1 tweeter endows it with a more sophisticated and complex sound than the C7ES3. In my 20x14' room I found the presentations similar, but the m30.1 was more lucid and less warm. I much preferred the later.
Some of the differences between these two may also be down to cabinet construction - the m30.1's thicker, braced, cabinet was obviously a bit different to the C7. A simple rap test showed this.

Upgrading from the 30.1s is a challenge due to the lack of criticism regarding Harbeth speakers in general.

Some of the above comments suggest that the bigger models in the range will give you more of the same as to what the M30.1s will give you. Alan Shaw has stated that he had tried to get the SLH5+ to sound a little more open than its predecessor (SLH5). 

However, these improvements seem to be of an incremental nature rather than anything dramatic. Heck! I've even read reviews where the diminutive P3ESRs  have been compared to the mighty M40s.

There really does seem to be a family sound between the models where even the M models (monitor series) share an affinity with the rest of the line. I guess  it's natural enough given that all models share the same material for the main driver and that the cabinets also share a similar construction design.

So it looks like it's down to the SLH5s or if funds allow, the M40.1s. I've read that they work really well for nearfield listening. Or just stay with the M30/1s which share the same tweeter as the M40.1s. Here's a great write up on the M40.2s. 

https://www.whatsbestforum.com/threads/harbeth-monitor-40-2.25222/

I'd be very surprised if the original Quads were an upgrade. They certainly didn't impress in my system. A totally different kind of sound, comfortable with even mids, but somehow sounded challenged at both frequency extremes.