I have a C47 preamplifier and it passed the dac direct to amplifier test of resolution. So those who say McIntosh is veiled compared to ARC are just full of it... or just tried older McIntosh pieces or their warmer tube preamps...
What kind of test am I talking about ? You connect a sota dac direct to your amplifier with sota interconnects. That gives you the ultimate resolution you should get from your dac. Then you add the preamplifier you want to test in the mix. It’s very easy to ear if you loose any resolution in doing so. If you don’ t loose anything compared to the dac to amp direct link, then your preamplifier is transparent to the source. Add to that the benefits of a preamplifier in the chain... a bigger soundstage, better dynamics and bass weight, a denser midrange, etc. Everything else another preamplifier can bring ( like ARC or any other you may like ) is either color, euphonics, and prat...to the taste of the listener.
That confirms the latest magazine tests of McIntosh solid state gear. Like the Absolute Sound review of the C52 preamplifier.