ATC SCM40A vs ATC SMC20ASLT

[solwisesteve]

First time posting for a couple of years, in which time it looks like my previous login has expired. Anyway, not a problem.

Some advice please. Previously I had passive 40's using ATC amplification and they sounded very good. However that setup went some time ago due to a house move and I'm now approaching the time to consider a new set of speakers. Naturally I want to go ATC :-)

I want active this time around and I'm considering the active 40's or, perhaps, the 20's.

I'm struggling to sensibly compare these two speakers, from the specs that is; I'll hopefully get my dealer to demo both options when I get to the buying stage. Meanwhile what exactly are the pros/cons of the SCM40A vs SCM20ASLT? The knee jerk reaction is to jump to the conclusion that because the 20’s are over a grand more then they must be better, but then the 40’s have the mid range driver. If it matters room size c. 25’ x 16’.

Can anyone please advise the good/bad points of each model?

Thanks

Steve

[SolarMusic]

if you previously had 40s with the ATC midrange driver, you might be missing something in the mids with the 20s. Listening at the dealer is best, of course, but I'd go the active 40's route if financially possible. You won't regret that. ;-)

[solwisesteve]

Looking at active in both models, 40 and 20. Never heard a bad word about the active 40's but, tbh, I've yet to hear anyone say anything bad about the 20's! ;-) As you say, at the end of the day, listening is the ultimate test :-)

[jophill]

if you previously had 40s with the ATC midrange driver, you might be missing something in the mids with the 20s. Listening at the dealer is best, of course, but I'd go the active 40's route if financially possible. You won't regret that. ;-)

Just for information, there's an interesting comment here attributed to ATC's Richard Newman and Ben Lily:

"What is the function of the soft dome grafted onto the mid/woofer in the two way designs from the HiFi Passive Series (SCM7, SCM11, SCM19)?
... The SCM19 is different. In this case the voice coil is 75mm (3”) in diameter, so the dome is larger; in fact the dome grafted to the former is the same as that used in our mid-range dome. The dome is designed to decouple from the cone at higher frequencies where it performs the role of the primary acoustic radiator."

The mid-bass driver in the SCM20 is the same as in the SCM19 IIUC. So, on this basis maybe you do get the flavour of the mid-range driver from the SCM20 and it's even the SL version.

The SCM40 will go louder than SCM20 (112 vs 108 dBSPL) so will drive a bigger room/listening distance with more dynamic range if that matters (but like all ATCs they are designed to do much better than the average in this respect anyway). And the SCM40 will go lower in frequency. As you write, though, it's always best for the individual listener to decide based on an audition.

[SolarMusic]

the active 20 pro model could be an alternative if you like black.
I got a good price from a ATC pro dealer for my pro model (scm45a) and they sound absolut hifi (not just for studio use)

https://www.whathifi.com/atc/scm20asl-pro/review

[solwisesteve]

tbh I don't mind the functional, black look of the Pro model. Not sure if SWMBO will though ;-)

[saureign]

If you have the room, 40s. 40s are more full-range. 20s are more refined, and their bass more layered, if not so low.

[solwisesteve]

At the moment I'm steering towards the active 40s but, tbh, the whole concept of the speaker purchase has been put back because it turns out we need a new roof! I don't want to even get the system out of it's boxes whilst that's going on. It might be spring '23 before I can progress with this and who knows, maybe I can find the funds for some active 50s by then! :-)