Dear members,

I have almost decided to buy ATC SCM150ASLT. But before investing big ammount, I still need to answer few questions. I will be very thankfull if you can answer some or all of them. There is no possibility to audition in my country, so I will need to take some risks and order anyway. Also local dealers usually know less and just care about selling more gear for more money. I would really appreciate that.

I am still a beginner in hi-fi world and this will be my first big system. I own near field monitors Genelec 8351, which I like. But I already want an improvement and I am looking for the big sound.

I mainly listen to electronic music, also ambient, down-tempo, nu-disco and etc. My music often inludes some instruments and vocals. I do not listen cheap mainstream EDM. I only occasionally listen to other genres like rock/jazz/blues/pop/rap and etc.

Few tracks to get an idea:



Question 1 - Models.

Do I correctly understand, that all these models sound totally the same? SCM150ASL Pro, SCM150ASL and SCM150ASLT. Difference is only in cabinet finishes and added accessories (grills, stands)?


Question 2. Room.

Speakers will be in a summer wooden frame-house. Made from 15 cm. glasswool inside and some drywall. Room has two big windows from floor to ceilings. Room dimensions is around 5-6 m. x 8 meters. Ceiling height moving from 2.4 to 2.8 m. I will ask for professional acoustician to treat my room after we install speakers. At least primary reflections and solve biggest room issues if we find any.

  • Is my room large enough for ATC SCM150ASLT? What is the smallest room recommended?
  • I have attached my room plan. How far from side walls and rear wall I shoul place the speakers? Is my plan good?
  • Speakers will stand in front of glass wall. I know it is not good. But still usable? What problems I may face and if it will be possible to solve them?

I understand , that nobody can guarantee the sound quality in a specific room. But I just need your guidelines if you have any.


Question 3. Pre-amp and DAC.

I will be listening only to digital files through my computer. Maybe I will add vinyls/cd and streamer after few years, when I will have extra budget.

My goal now is to get maximum out of my speakers, with buying least needed boxes, but best quality, so they match my speaker quality and price range. I do not understand if I need pre-amp and if it affects sound quality.

Please help me to get right strategy what to buy now, and what I can upgrade later. And how big adding better dac or pre-amp affects overall sound quality.

So questions are:

  • Can I just buy best I can afford pure DAC (with analogue sound level control) and go straight to my active speakers (so there is no pre-amp in my system at all)?
  • Or I need DAC, not pure, with some kind pre-amp funkcionality?
  • Or I need to buy pre-amp and Dac (separate boxes)? Would that improve sound quality a lot, because of pre-amp in the system?
  • Or I should better buy best DAC I can and add pre-amp later? Or otherwise - I should buy now best pre-amp and simple DAC, which I can upgrade later?

If I am getting it right, I do not need a pre-amp now, if I play only digital files from my computer. I should now buy best pure DAC I can and which matches my system’s quality and price range, am I correct? Later on I could add pre-amp (I would choose ATC SCA2 pre-amp for brand synergy), which would improve sound quality just a little bit, but I could add vinyls also. Is that correct?

If yes, could you give reccommendations for pure DAC, that are known for good synergy with ATC? Which model could be good match for my system in terms of quality and price range? Should I invest in DAC like 5-10k.€ to get most of my speakers?


Question 4. Updates.

ATC models have been updated quite long ago. And ATC 50 year aniversary is coming next year. Would it be wise from my side to wait till let’s say Munich Hi-Fi Show to see if there are any big news from ATC? 

I would be very sad to buy my first big system and find out that it was updated just few months later…


Question 5. Audition SCM150ASLT.

Do you know any place in upper part of Europe like Poland, Germany, Scandinavian countries, where I could go and audition ATC SCM150 model? I would fly there to listen before buying.


I will be very very very thankful for all your answers 🙏




I'm jealous. I would love to have an ATC factory tour one day.

Perhaps I can one day convince Rick or Sir Paul for a personal audition in their studios. The picture in the attached link shows ATC active pro monitors in the background. I'm guessing both know something about good sound...

Rick & Sir Paul


I don't think any of us in the business have anything more important than helping anyone considering/owning/using ATC.  I believe you cannot "sell" things, you have to "explain things" and people will make their own judgements.  These are investments that have a long life.  I just got a pair of 50s in the shop that were built in the 80s.  

I send studio and home people to Ben at the factory regularly - we have worked together for years.  I visit him there as well and know all the people at the factory.  When he visits the US, we take him to US studios and dealers.  He was just here and few months ago, did an ATC event at Audio Hunters in NJ and then took him to Nashville to meet my Nashville staff and visit several major studios like Blackbird.  Leland, who runs consumer for us attended so he could see what real pro looks like- serious audiophiles that happen to do sound for a living!  


@lonemountain wrote:

What Pat was talking about was narowing of dispersion behavior of all cone drivers as frequency increases- this is a true. H. owever, ATC crosses over from a woofer to a midrange driver at 380Hz, extremely low for a 3 way. This is well below the frequency of significant performance degrading HF narrowing. This is a more relevant criticism of a larger cone woofer 2 way, say something like a 8" or larger 2 way. 2 ways typcailly cross much higher, as dome tweeters do poorly below 2K. From 1K to 2K there is significant narrowing of a cone woofer.

380Hz isn’t a low cross-over point in a 3-way system, but in a 2-way ditto it is, and with a conventional, direct radiating iteration with a dome tweeter that’s not going to happen. That is, unless perhaps we’re talking about the use of a coaxial driver; crossover points seem to leave their distinctive mark more as spread-out point sources that also invite timing issues between the driver elements and proper summation at different listening positions, rather than the crossover points themselves via a single point source, or emulated with a Synergy horn. Another matter is the power response at the crossover points, which is mostly left wanting with dome tweeters and coned drivers.

In horn loaded systems, the rules are different. Now dispersion is determined by physics, throat size and horn mouth size and design. So the net result is that narrowing at HF is still present in horns/driver combos, and it can be somewhat severe in older horn designs (its why multi cells were invented to try and create lots of small dispersion lobes instead of one big one). Bob Keil did a lot of research on this for multiple audio companies a long time ago and is credited with developing the entire constant directivity design approach (which helped raise the narrowing frequency quite a bit and improve fidelity of horns a lot).

Don Keele did great work developing the Constant Directivity horns. Here you can have a low crossover point with a 2-way system in the ~600Hz range to a 15" woofer/lower midrange without any notable issues, while having great dispersion pattern at the crossover, prodigious output AND low distortion.


I think you misunderstood what I was trying to express.  380Hz is the crossver point ATC uses from woofer to midrange (in active or passive versions of their 3 ways) therefore avoiding the worst narrowing effects of the various sized LF drivers exhibit when run up to common crossver points.   The HF crossover from the mid dome to dome tweeter is 3800Hz.  BIlly was very keen to develop a consistent off axis speaker as he was adamant about off axis relfections need to be consistent with on axis information to preserve imaging even in highly reflective environments. 

Don yes, very nice guy! A [product] engineer's engineer..  Met him multiple times at EV as he was responsible for the "white" EV horns that lead the way in the 80s.  Course EV was using a  1.3 inch driver/throat for their horn so that made crossing low difficult.