I suggest getting the SCM19 as they incorporate the 3" dome in their midbass. Even though they would make the speakers more revealing, that is what makes ATC so unique. The more revealing they are, the more it will show your upstream equipment's signature sound. You want a warm tone, you can get a warm sounding tube preamp from cary or mcintosh, if you want the most accurate sound possible, you can opt for a bryston or pass lab preamp, and if you want somewhere in the middle, you can get a parasound halo preamp..and so forth.
The most important is to get an accurate power amplifier with stable current. Class A, or high bias Class A/AB amp works well. Krell, Classe, Pass Lab, Vincent Audio, and Brystons. However, I have use old class A/AB amps like Parasound HCA-2200II with 250watts per channel. Even though it was alot of wattage, it was grainy and harsh at higher volumes with very thin bass (using a sunfire TGI and parasound preamp). So just make sure the amp is "SMOOOTH".
BTW, here is an response, i wrote a few months ago, that may also help you:
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One of the major difference b/t the 19 and the 20 is the tweeter. The older 20s uses a vifa tweeter and the newer 20s uses a seas tweeter. Both EXTREMELY revealing and very smooth, with the seas having a bit more detail (very hard to hear a difference, but better specs are better specs)...same goes for the non-SL vs the SL spec-ed 20s. I can't hear a difference really...but that is probably because I never hear it in the same room, and I always ask to demo them on tube-preamps.
The 19 uses ATC inhouse tweeter and are more meant towards home usage. ATC tame down the speaker so that the average recording sound a bit easier on the ear...although they are still very unforgiving.
The SCM20 and SCM20SL to the SCM50, SCM100 were meant for pro use. The ATC SCM40, SCM35, SCM19, SCM11, and SCM7 are meant for home use. Although they both carry the signature sound, they are quite different. If you are used to the "pro" sound you may think that the Entry Series may lack something. I tried going to the Entry series, but the sound is not as detailed nor is the speaker as transparent to source change. This does not mean the Entry series is not as good. Both series are like intensive X-Ray machines, its just that the Pro will do the full X-ray and has a zoom-in feature if you know what I mean.
But those are still very minor critiques. Both Pro and Entry level are great speakers. The entry level will trump most speaker if you are looking for the most uncolor speaker you can find.
Just remember to power them correctly if not, the ATC will be the most ugly sounding speaker ever. You will hate them. Also take into account that most of your recordings are will be unbearable to listen to, even with great electronics. They will spit out what is fed. If you look at my system, I used 2 huge monoblock class A amps to power them. However, I opted for a tube preamp because 75% of my music collection are not perfect recordings.
If you want the most extreme of the extreme, you can always opt for an all byston setup with the ATC. Then you have a system that is so precise it can surgically remove the music bit by bit.
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The most important is to get an accurate power amplifier with stable current. Class A, or high bias Class A/AB amp works well. Krell, Classe, Pass Lab, Vincent Audio, and Brystons. However, I have use old class A/AB amps like Parasound HCA-2200II with 250watts per channel. Even though it was alot of wattage, it was grainy and harsh at higher volumes with very thin bass (using a sunfire TGI and parasound preamp). So just make sure the amp is "SMOOOTH".
BTW, here is an response, i wrote a few months ago, that may also help you:
---------------------
One of the major difference b/t the 19 and the 20 is the tweeter. The older 20s uses a vifa tweeter and the newer 20s uses a seas tweeter. Both EXTREMELY revealing and very smooth, with the seas having a bit more detail (very hard to hear a difference, but better specs are better specs)...same goes for the non-SL vs the SL spec-ed 20s. I can't hear a difference really...but that is probably because I never hear it in the same room, and I always ask to demo them on tube-preamps.
The 19 uses ATC inhouse tweeter and are more meant towards home usage. ATC tame down the speaker so that the average recording sound a bit easier on the ear...although they are still very unforgiving.
The SCM20 and SCM20SL to the SCM50, SCM100 were meant for pro use. The ATC SCM40, SCM35, SCM19, SCM11, and SCM7 are meant for home use. Although they both carry the signature sound, they are quite different. If you are used to the "pro" sound you may think that the Entry Series may lack something. I tried going to the Entry series, but the sound is not as detailed nor is the speaker as transparent to source change. This does not mean the Entry series is not as good. Both series are like intensive X-Ray machines, its just that the Pro will do the full X-ray and has a zoom-in feature if you know what I mean.
But those are still very minor critiques. Both Pro and Entry level are great speakers. The entry level will trump most speaker if you are looking for the most uncolor speaker you can find.
Just remember to power them correctly if not, the ATC will be the most ugly sounding speaker ever. You will hate them. Also take into account that most of your recordings are will be unbearable to listen to, even with great electronics. They will spit out what is fed. If you look at my system, I used 2 huge monoblock class A amps to power them. However, I opted for a tube preamp because 75% of my music collection are not perfect recordings.
If you want the most extreme of the extreme, you can always opt for an all byston setup with the ATC. Then you have a system that is so precise it can surgically remove the music bit by bit.
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