Atc smc40


I couldn’t imagine buying sub for 40’s. They really go much deeper than specs say. ATC is very conservative with specs on the website. For example I’ve auditioned Spendor D7 in my room with same setup and it was much lighter in bass and extension even though it’s specced at 29hz vs SCM40 48hz (-6dB). Almost 20hz difference and still ATC outperforms it. So once again I recommend auditioning before drawing conclusions. Specs don’t tell much.


I agree the specs are very deceptive. In my 4m x 4.3m room the bass from SCM40 was too much. With a sealed box design like SCM40 the bass drops off a lot slower compared to a ported design. This explains the modest spec but in reality it barely drops in level from 50hz down to 40hz.


Yes the specs are not necessarily that representative of actual in room performance. My 19 passives are fairly strong down to about 35Hz in room according to my calibrated frequency response meter using pink noise, and I actually attenuate the very deep bass in DSP to stop rumble and add punch…I would imagine this would be even more the case with the 40s with their slightly lower frequency spec.

Makes you realise how damaging subs can be unless critically profiled to match your room and listening position for natural music… special fx is something else.

And of course the 19s have the world renown bass mid dome driver borrowed from the pro range, that provides some of the lowest conventional loudspeaker distortion out there…


I had Dynaudio contour 3.4 s before, which went lower, hence my reason for the lower bass.i am fortunate in having a largish room, but didn’t want speakers too dominant, and cost cf to the 100 A which are mega expensive. Plus you get the mid range driver that ATC are renowned for, with the 40.
The result I have to say is very pleasing.I only notice the sub when you turn it off, the REL is an excellent , no desire to change, which I have to say is a first in Hifi. Even down to speaker cables, I just use the ones that ATC made for me,which I believe are std studio mike screened cable.


Yes that midrange is wonderful, its in all their speakers from 40 and upwards.


Where’s your rumble coming from?


It comes from some albums… though many modern albums do have eq to stop very low bass… I think it can interfere with some of the mastering compression techniques


I ordered Mogami 2549 xlr-xlr cables and also rca-xlr, just in case I need to connect 272 or something similar to the system. Still waiting for the 40A’s but meanwhile 19A’s are starting to open up better. This is pretty new pair so it’s not yet fully burnt in. Mytek Brooklyn DAC+ in front.


I been following this thread with great delight.

I’ve been auditioning the passive 19v2 with my naim NDX/282/HiCapDR/250.2 setup for the past week. It’s incredible!!!

My room is 4m x 12m

My dealer is selling off all the ex-demo units at heavily reduced prices.

19 passive and active
40 passive and active

So my decision is:

  1. drop out the NAP205.2 amp and go active
  2. keep the 250.2 and go passive
  3. 19 v 40

OMG a very tough decision. Is there a $$ for $$ best scenario here?

I’m sure many of you have faced the same decision.



If your room is that huge then go 40’s, no question there. I have A LOT smaller room and felt that 19 wasn’t enough there. 250.2 will drive them but I’m positive you get better results going active. My pair should leave from UK to Finland today, can’t wait!


Go for active 40s for sure, no regrets


Anyone tried connecting 552 to 19a/40a?


It’s hard to part with a perfectly good 250.2!


Have you tried the actives yet to see whether you actually like the active sound espescially over long periods? You have tried the 19v2 with your Naim system and you said ‘its incredible’. If you go over to actives without audition its a bit like the Brexit scenario- the unknown…


That’s the next step! Great suggestion.


Hi, yes ATC are renown for their mid performance, possibly something to do with professional pedigree. The 19 has its renown mid dome combined bass driver borrowed from the professional studio monitor speakers, which provides some of the lowest distortion out there for a conventional speaker for a high performance (ie no crossover required) and the 40 uses a seperate driver for the mid with careful cross over design to minimise the added distortion, but compensates with its dedicated focussed mid range performanc from a single driver.


I ordered Metrum Acoustics Jade DAC/preamp to try with SCM40A’s when they arrive next week. 30-day trial period so it’s risk free. Goes offtipic already but does anyone have experience with Metrum products paired with ATC?

I also have RCA-XLR cables arriving today so I can try the active ATC’s from SN2 pre/sub-out on my old system.


I have read online some interesting reviews on the Jade espescially to its DAC. Look forward to your report .


Yes, the 40 uses the iconic dome mid range, the company was founded upon. It is apparent on listening how good ATC drivers are, especially with there very low distortion, and lack of compression at very loud levels.
I have had many speakers over the years, most very very good, but I have to say that to my ears ATC, especially in active form take some beating. Although as anything to do with hifi it’s very personel.


Yeah the midrange driver brings most of the magic I think. When I compared passive 40’s to my PMC 20.23 back in 2015, I was blown away immediately. It felt like PMC didn’t have midrange at all or at least it was completely hidden compared to 40’s. Of course 40 is much bigger speaker than 20.23 but there was really no competition between these two.

I currently have PSAudio DirectStream DAC/pre connected to active 19A’s. This must be the best digital sound I’ve ever heard. I didn’t expect much but really, it does everything right. Smooth, enjoyable top end without sacrificing details. Dynamic and punchy sound with great reach in low end. With this source, 19A’s goes clearly deeper than before. Mytek just couldn’t reach the depths these speakers are capable of playing. It even clears the most difficult part after listening to Naim for 10 years, PRaT. Not quite as forward as Naim but still pretty much perfect. I really hope Metruc can match this since this active trip might get super expensive otherwise.

I still haven’t auditioned NDX2 straight to active speakers through variable output but it interests me a lot. Probably will test that one also before making final decisions. Active 40’s are little bit late, should be here somewhere in the middle of next week. Same with Metrum Jade.