ARC and CJ have quite a different sound. I'm not sure how it was in the 80's back. ARC's recent gear has turned me away. I've heard their stuff mostly with B&W and a bit with Martin Logan. It's difficult to put into words but the ARC gave me a feeling of gray and industrial. The operative word is "recent", I heard a VT-100 driving a pair of ML ReQuests, not sure the pre and I think the source was a Wadia rig, this system gave a presence that was down right scary.

I think when Mac started building transistor gear they tried to keep as close to the sound of their tube gear as possible. It may have been the set up to blame, when I heard Mac's expensive HT processor I was not impressed. Listened to a Anthem AVM-30 at the same visit and it sounded much better. I've heard some great Mac stereo gear though. Mac is also one of the hottest products on the used market. From what I can tell Mac and CJ have in common, both have a certain "house", or signature, sound and try to stick with that as much as possible no matter the product.