ATC scm 19 vs ATC scm 20SL?


What is the differences of these monitors?
Wich is better...
powerestudio
Bob,

IMHO, it is the the extended bass (down to 40 Hz) that you get with the bigger models. A large woofer will pressure up the room. It may be something we not only hear but feel. In any case you can definitely achieve similar results with a sub and smaller monitors. And yes a subwoofer has a ridiculously difficult task. Finding a sub that is powerful enough to play as low as 25 Hz with 115 db SPL and very little distortion or heavy compression is as rare as a needle in a haystack (ATC make one but it costs nearly 10 grand). Nearly all subs start to distort/compress at about 105 db SPL at 20 Hz (yes - I am even referring to the big big expensive ones)
Hi Folks
Just to add to this thread, I have recently purchased the ATC SCM19's after about 5 weeks of research as there was no dealer in my city up here in the Great White North. I can assure you that they do indeed have the SL(Super Linear) driver assembly and they are built like cinder blocks!!. I am running my particular pair through a Wyred4Sound ST500 Amplifier (250w rms @ 8 ohms) with great results. The bass from these speakers is really something else. I had a pair of totem hawks before I purchased the SCM19's and quite frankly the Hawks fall short in both performance and bass compared to these ATC SCM19's. Awesome speakers for the price,true sound with a great sound stage. Any other questions people may have before purchasing these let me know I will try and answer as much as possible,Thanks.
With ATC its a simple to understand their line up. There are passive 2 ways and three ways; there are active versions of some of the 2 ways and all of the three ways.

The three ways add ATC's proprietary mid dome, now copied by a lot of others, dropping midrange distortion by a LOT. This is what makes them so popular in recording studios. With the three ways, you choose how loud you want them to play and how low you want them to go (woofer size). Other the bottom end, all the three ways sound very very similar to each other, enough so that you can use larger ones in front and smaller ones in back in the typical multichannel 5.1 or more rig. Pink Floyd Dark Side 5.1 was mixed like this by James Guthrie, with 150s in front (15 inch 3 way) and 50's on rear (9 inch three way).

Brad
I own an ATC SCM20 SL since 1992. It is the oldest piece in my chain. I had a love-hate relationship, but I am glad I kept them. While they provide a rather dark, mid-hall sound, they brutally reveal any weakness in the chain. They are especially sensitive to any sibilance and "digitits".
I modded them heavily, with all Duelund crossover components, ring radiator tweeter and C37 lacquer. They are unique in combining intimacy with force. The Quad ESL63 had a similar "intimacy", while seriously lacking force.
I am happy now, driving them with Nuforce 9V3 SE, Metrum Octave dac, Audiophilleo2 and ASI liveline cables.
My dream amps would be Spectrals though...
How can you do a driver swap without destroying how they were originally voiced? I don't want to sound too critical as I have done this very same thing with 1985 vintage ProAc's. The tweeter replacement was from the Response series (i.e. one silk dome for another).