ATC SCM 40 mk2 vs Salk Song3 Encore

Any ATC folks care to share how far they have their speakers from the back wall (from the back of the speakers, I mean)? I can do up to about 16" and I was thinking I'd start from there, but if 12" or something works better for anyone... They're big and heavy and we're seniors so the less fiddling the better. The same goes for toe in.
I just mean generally, not specific to a certain type of room.
Thanks.

Would a Musical Fidelity A308 bring them a clear and strong enough signal? And I use Deezer CD quality through a $400 dac.

Thanks!

Thanks, everyone.
I found an amazing deal for the ATCs and pulled the trigger. If I hadn't, it was going to be a Salk. Clearly, I wouldn't go wrong with either.

Yes, the 40's mk2.
I lucked out.
I'm excited.
I just hope my wife can hear the difference.
m.

Thanks. I couldn't have ended up with these without y'all.
Since they had a ding and a few nicks, I got four year old ATC 40 mk 2s for 3400!
That ought to leave some cash on the table for upstream stuff someday.
Marc

I have to wait until next Monday for the speakers to arrive. Aargh.
Any suggestions for where to sell (local pick-up) vintage KEF references?
(Besides here, of course).
Thanks.

Thanks. I'll do it.