That is exactly why I find them not so enjoyable.
Whatever model I've heard so far, the enclosure singing along has severely disturbed my listening pleasure.
Like you say, when you're used to and like dead silent cabinets like with Magico, YGA, Vivid Audio, Harbeth is a no go.
Sorry to be the party pooper here.
Hello Bart,
This is really a question of taste. I cannot hear this "resonance" in Harbeth speakers. Neither they can sound "boxy". Actually if you open a pair you can see easily that the cabinet walls are not thin at all. They are about 17 mm which is pretty thick for a wood speaker.
The old story about resonating thin walls come actually from the original BBC LS3/5a.
Now if you knock on a Harbeth cabinet with your hand, you will have an idea of how dense and heavy and actually non resonant these cabinets are. Moreover, Harbeth speakers are extremely heavy. The P3ESR for example is at least 2 times heavier than the Stirling V2 LS3/5a. The 30.1 is much heavier than most similar british wood speakers. And I don't even mention the 40.1 which is a monster compared to the Spendor S100.
Something that is impossible to deny, no matter your tastes, is the incredible linearity, coherence, purity, naturalness of the Harbeth mids. To me this medium is not only the best in the world, it is far better than any other one on the market.
If the speakers were really "resonating" at a frequency that the human ear can get, then, it would just be impossible to reach this quality of the mids.
Last but not least, I cannot listen to Magico, YG ( never listened to Vivid), BW...and other supposedly non resonant and highly inert cabinets, without getting angry and frustrated and horrified and...
just cannot end this list !
They sound just sterile and cold and they do not communicate any emotions to me.
Envoyé de mon iPhone en utilisant Tapatalk
The Harbeths are moving me in ways I have never been moved before. 
How you like the GA so far ? I'm loving what I hearing vs BIG7 I had 
