You have some important decisions in front of you. I would go for the preamp. The decision of Mac or Audio Research Corp. is a good one and very critical. These are two vastly different solutions. I personally am firmly in the ARC camp, not because it is better... but because of its sonic characteristics. It is very detailed, very natural, not lacking bass or midrange bloom. The classic compliment of Sonus Faber is ARC with Transparent. Over time I have slowly migrated to all ARC Reference components with my Sonus Faber Amati Traditional speakers and all Transparent Ultra Gen 5 interconnects. I like all kinds of music.
.
MacIntosh is also a well loved sound... they look great and are known for their slam and midrange but are somewhat lacking in detail. The analogy I like is Mac is the American muscle car the ARC is Imported sports car. If I listened to primary rock I might be more inclined to buy Mac. I highly recommend sitting down in a showroom with an all ARC system and a MAC system. To me I can tell which it is in seconds. I have spent lots of time with Wilson as well. Amazing sound! Loved listening... but not what I want to listen to every day. Each company has a house sound, you want to find the house you want to be in. Mixing different sounds can work... but you can end up having the components work as filters. If your source is a bit soft in the top end, and the preamp is good with high end details but weak on the low end and the amp is warm... you might achieve the required tonal balance, but the source cut out high end detail, the second cut out some of the bass detail and the amp can’t amplify what it didn’t get so you are soft on top amd bottom, well, you see it’s complicated. The level of performance you can expect from your speakers is very high, you want to make sure to carefully choose components so you get everything out of them you can. I have had three sets of Sonus Faber after three decades with planar and hybrid. I will not be changing.
Also, the audio source is REALLy important. I started at the bottom with a laptop (iPod before that) and stepped up to a Aurender WE20SE... and the biggest change was the last... this is a world class source and profoundly impacts the sound like a great turntable / Phonostage effect the outcome.
.
I have a separare home theater... I am not nearly as critical with that system since I am distracted by the video. However it is still a great system B&W 805 all sides and 2 800 series subwoofers.
Given your existing components...you plan of separate home theater and audio system is a good one. Combined purposes always result in substantial compromise... given the components you already have it would be a shame to compromise the potential.
