Take a look at Tire Rack for the tires that tested as being quiet.

+1 for the Michelin PS4S's. Went from Hankook Ventus V12 Evo's and it is a night and day difference. Low speed cornering on the Hankraps sounded like I was grinding on the rim. Ride has also improved with the PS4S's. Tirerack reviews shows these as being the quietest.

You'll want to look at Grand Touring All Season tires, which are specifically engineered for quiet & comfort, without too much performance loss.

while I agree that quiet and comfortable go with Grand Touring All Season, I have to disagree with this: "without too much performance loss".

That IS a subjective statement AND observation to each person, but in my experience you will be giving up ALOT of sidewall stiffness / performance when you choose a tire rated in the Grand Touring segment.

You have to stay in the High/Max performance category to utilize the full potential of this car the suspension setup.

gr

+1 on this.

The GT tires I have (General Tire) are pretty "numb" in terms of feeling and hence makes for a nice, quiet and boring ride. They do NOT grip as much as PZeros, for example. This is possibly a subjective opinion but I had PZeros on BMWs and now Audis and they have similar road gripping characteristics.

Having said that, the Grand Touring tires are plenty fine on highway driving, straighaways where I want to accelerate fast but not worry about turning/cornering capabilities.

My 2018 S4 came with Hankook Ventus (or whatever they are called) and those are quite numb and lack grip but are very quiet and comfortable on the highway.

Mine received the Contisport 6 as OEM fitment. Note there are several versions of his tire in this size, even amongst the Audi OE designations. Mine are RO2 version.

We we have the Michelin 4S on the TT, obviously a much louder car than the S4 with a different suspension so hard to direct compare but I find both tires more than acceptable from a noise comfort standpoint for a performance tire, though it sounds like the contis are a touch louder. I really wish Audi would use Michelin for OE tires, as well I really wish they would dump Hankook (those were OE on the TT). Though I did see the Michelin 4S on an R8 in the showroom.

Toyo 4+
That's what I'm getting when I need new tires.

B9 S4

The Bridgestone Quiettrack should be your best bet, period.