ATC SCM 40 question


I recently bought a pair of ATC SCM40 speakers. I have them placed in a room approx 12ft sq. They are on the back wall, seating on opposite side. I can't move the speakers into the room or move the chairs into the room as I barely got away with buying these and can't encrouch any further, the missus was not happy at the size of them!

Anyway, they sound pretty incredible a lot of the time, but I've noticed on some recordings, not necessarily bad ones, just they can come across a little shrill and sharp, like the highs are overheated somehow.

I'm driving them with a PS Audio S300 Poweramp, that is being controlled by an RME ADI 2 DAC. 

I've tried messing with the dsp settings on the RME but I just can't seem to ease the issue.

My question is, does this seem like an equipment issue? Or maybe a cable issue?

I don't want to end up spending serious cash upgrading the amp or dac if that is not the problem. But I know the SCM40's need a lot of juice and the S300 only has 140w per channel, and the recommended is 150w. Or is that just a top end volume concern? I'm already looking at the Hegel H20, I can't get the ATC poweramp as I don't have the space for it.

Also I was looking at the Anthem STR Preamp. Something that might calibrate the sound better for the room. Maybe a cable upgrade?

Anyway, these are just my rambling thoughts on an ongoing issue, any advice at all would be much appreciated. I really want to solve this as when these speakers sing, they really sing!



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Dave and Troy

Audio intellect nj

Atc dealer 



That's a small room. Do you have any treatment behind the speakers or on the side wall at the first reflection points?

What kind of speaker wire are you using? Do you have them firing straight ahead? Try changing Toe-in, etc.. And yes, room treatment.

Are these new or the original version?  I don’t think driving your amp with the RME DAC is doing you any favors here so you might entertain adding a good preamp, and it’d be good to know what cables/interconnects you’re using.  Do you have a carpet on the floor?  Also, you could try to tame first reflections on side walls and maybe try putting some felt around the tweeters.  Just some thoughts FWIW.