I owned the Harbeth m30.1 for 6 years and think they are a very enjoyable speaker.
While I wasn't diisatisfied with the m30.1, I had the opportunity to hear the ATC scm19 and ultimately sold the m30.1.
I was very surprised that I preferred the ATC mids and they had far more neutral and punchy bass. A great little speaker with a lot of pedigree - and ATC make all their drivers themselves.
Perhaps a downside for the ATC is that they require a pretty hefty amp - 100W plus. The Harbeth played well with lower power amps. Neither are difficult loads though.
While I wasn't diisatisfied with the m30.1, I had the opportunity to hear the ATC scm19 and ultimately sold the m30.1.
I was very surprised that I preferred the ATC mids and they had far more neutral and punchy bass. A great little speaker with a lot of pedigree - and ATC make all their drivers themselves.
Perhaps a downside for the ATC is that they require a pretty hefty amp - 100W plus. The Harbeth played well with lower power amps. Neither are difficult loads though.