ATC scm 19 vs ATC scm 20SL?

I've never heard an ATC (but would love to someday).

Bob it is true that diminishing returns are reached quickly in small active monitors (much quicker than passives). Veneer and good looks do add significantly to the cost and these are real cost factors not markup - although they do nothing to improve the sound. Provided one accepts a near field position and does not demand realistic live SPL then the choices multiply.

The big ATC's are kind of mind blowing but they also suffer from diminishing returns because the SCM20 is already very good (even the passive version). It is a matter of degree - the smaller speakers simply cannot do large orchestra or big band with quote the same aplomb - so they are not quite "you are there" - the dynamics from percussion is not quite what you get from a real drum set. The larger ATC speakers get you all the way there (a point where you simply cannot imagine better other than a live band or just a slightly different but equally good presentation) - but the extra cost is almost certainly into diminishing returns.

All ATCs sound excellent on vocals. In fact in a blind test based just on vocals, it can be extremely difficult to differentiate between two ATCs. I have heard even their smallest SCM7 and even those had a very similar lifelike palpable vocal like my SCM40. Unlike many other brands all ATC speakers sound very similar with similar strengths and (weaknesses ?).

Agree with the last two postings. ATC speakers are somewhat unique in that they are very neutral and unforgiving, qualities that professional sound engineers value. I have owned many versions of this speaker, all the way up to the 150s. I presently own the 16as at work and for the money, I think they outperform most speakers in the price range, and along with the 11s and 19s, represent the best consumer oriented speakers. I buy mine from their pro distributor in Las Vegas. They are bombproof in build quality. They are made for audio bays/worker cubes, and remember, most tracks are mixed down around the vocals. To Pani's point, you can easily distinguish them in a honest fashion, and from a engineer POV, where they are fusing together different takes to make a holistic song.

The only other speaker I have heard that match the ATCs are the new Sony speakers that grace the cover of the new Stereophile Magazine. Heard them at the T.H.E.Show in Newport two weeks ago and they were jaw-dropping beautiful, driven by Nelson Pass electronics. They are 27 thousand, a little bit shy of the price of 50s and 150s, but a beautifully smooth cross-over and very dynamic.