One of the hang ups with OEM car audio is the Harmon Group makes Harmon Kardon, Infinity and Mark Levinson systems. In addition, they licence and build Bang & Olufsen and Bowers & Wilkins car audio systems. One company is solely responsible for 5 brands!
So much for competition and less opportunity for high definition options!
Recently got a new Lexus with the Levinson upgraded audio system. I’m pretty impressed. The improvement over my 12 year old Infiniti Bose system is substantial. There is an actual soundstage across the windshield. Maybe not a completely natural soundstage, but I’ll take what I can get. I’m a little surprised that it was only $2,900 for the upgrade, which includes the nav system.
Minor update… no crazy processor upgrades to my Audi SQ5, but I did add a $300 RSNAV Carplay unit. (No Carplay natively in this car.)
I won’t claim that sound quality is improved (I think it is, tho!), but it sounds great playing Tidal/Qobuz/Radio Paradise via a wired connection from my iPhone. (You can use Bluetooth, but I think wired sounds better, and I have it plugged in and charging by default anyway.)
Also love using my go-to Google maps over the Audi navigation.
Unit’s a little bigger than a deck of cards, and it fits easily behind the head unit/climate controls. All harnesses were included, and there are a few videos out there on installation. Pretty easy.
Biggest pain was having to buy a OBDII device to access Audi’s hidden menu so I could activate the Auxiliary audio input, which is turned off by default. 
Other than that, very happy with it.
I’ve agonized over this issue since my youth.
I even took apart my 2013 Jetta wagon and installed Hush-Mat inside the doors, floor and hood to reduce road noise with limited success.
Like others say, it’s a car and there are only a few examples of ultra low noise interiors. I have read the super high end Range Rovers are scary quiet.
In my Volkswagens, I tend to stick with the stock stereos and stream TIDAL via Bluetooth which doesn’t sound great but that’s where I am.
I still look at new head units and am tempted every few months to install something like a Pioneer, JVC or Kenwood that has Android Auto and iOS CarPlay.
There’s only so much you can expect in a car environment. I used to build SQ systems in cars and compete. The only way you can get anything close to what you would at home is with a full interior rebuild, DSP and, being stationary. If you’ve swapped the factory speakers and amps, added a dedicated sub and, added a ton of sound dampening material you’ve gotten 90% of what’s possible. DSP is also good if you only care about what it sounds like in your seat and nowhere else. The last 10% is ridiculous in terms of price, time and, usability.
In my VW MKIV R32 I did put in a Kenwood Carplay headunit in place of the Monsoon. Vast improvement. (But, to be fair, I replaced the speakers and added an amp and subwoofer at the same time.) 
I’m surprised an Audi does not come with CarPlay and Android Auto standard.
They are smart adaptations by automobile manufacturers, given how many live on their phones.
Mine is a 2017 (B8), and I do believe the 2018+ chassis (B9) does have Carplay.
Don’t quote me on that, but I think it does.
Nearly all 2018 and new Audi models have Car Play and Android Auto. Some 2017 models (Q7) had it. There are still a few base model vehicles which don’t though.
The Germans are smart car designers but can be slow to adopt none driving related technology.
Ironically, VW started adding Car Play & Android Auto to some 2015 models. They have a good touchscreen interface as well.
Our 2017 VW Golf Alltrack had CarPlay.
I love the sound system in my BMW 5 series. It’s the ‘standard’ sound sytem (not the Harman-Kardon, nor the Bowers & Wilkins), but it’s really good. It has very good bass, even at higher volume levels it sounds perfect. But…that is only the case when I listen to the radio. When I play mp3 or flac on a usb drive, the quality isn’t nearly the same. Bass is not nearly as good. Overall quality is nowhere near radio quality actually. And I even notice a significant difference between files with the same bitrate (320), It’s weird… But when I play those mp3/flac files on my computer, using only 60 EUR/68 USD headphones, they sound GREAT… It’s driving me crazy.
Welcome, @Mario70 !
Welcome @Mario70
Congratulations. You have a lovely SUV. I had a similar case with Lexus RX350. It turned out that I have to set sound parameters separately for each input because they do not share these settings.
I hope it’s the case with your car audio too.
I will warn - do NOT invest in an Audison Bit Play HD. I shelled out a grand for this in 2015 - here’s a review I posted a while ago:
Well now it IS 2017, this piece was a complete waste of money. The firmware shown in their 17 month old promo video is STILL not a reality, although it DOES sound great, it is virtually unusable as a mobile piece. Unless you are using it on a long trip where you NEVER stop… average boot up time is about 5 minutes, (longer if you have a USB drive as well as the internal SSD) then you have to select (via remote only) a source, go to a folder, find a selection & play. Well crep, I’m already at WORK now - I heard 38 seconds of a song on my 9 minute drive…. this time. I’ll catch the rest on the way home – But NO…… after work - another 3.5 minute boot up – and now I gotta start ALL over again and RE-find that song and start from the beginning. Awesome. Purchased in 2015, no updates, no announcements, I’ve BEEN patient, I emailed the company regarding firmware - no response, I had high hopes, but I guess it is time to flog this piece of Eurodung and get a Sony RSXGS9 player…… So I have a Bitplay for sale - going cheap - it only has about 3 hours of play time on it…
There was a firmware update but it is still painfully slow & virtually unusable as a mobile piece. The graphics & UI are like an 80s 8 bit video game. Disappointing as I was very excited to get hi-res & DSD in the car.
Buy a fast car so you can hurry home to your stereo.
Contrary to most people’s opinion, achieving extreme fidelity mobile sound (in the right car) is indeed possible. You just have to throw enough money at it. Eons ago when I worked with Alpine they had a staff purchase program here in Canada - once a year you could buy as much gear as you wanted at 50% BELOW dealer cost. That equated to about 1/4 retail. (You had to sign an agreement stating you would have it installed in your car and you would not re-sell it within the year.) I took advantage of this over the years and upgraded annually - stopping when the old school beefy gear gave way to less industrial stuff. The sound in my car is jaw droppingly delightful and very intense. Finely tuned, each speaker is crossed over & time aligned to the driver’s position. There’s an extreme duty Odyssey PC-2150 battery in the trunk, and at around 4000 watts, if I run the system with engine off at a substantial volume, it will kill the battery to the point of audio shutdown in about eight minutes. Some things sound best in the soundroom, some on the headphone setup, but everything sounds great in that car. Up until my current soundroom setup, that car was the best audio sound I’d heard.
Best demo tracks in the car - Joe Bonamassa - Live at the Royal Albert Hall. Dual drummers, one in each channel and when they each strike their snare a millisecond apart - the effect is spectacular in a small enclosed environment.
I think - in the day - had I paid retail and had to hire an installer, the system would have likely fallen into the $20 - 25K region.
1995 Thunderbird Super Coupe: (Previously a sheriff’s car in Texas - 5 speed - one of 575 built)
Alpine IVA-D901 DVD screen - Highest resolution screen they ever produced
Alpine PXA-H800
Alpine RUX-C800
Audison BitPlay HD - Garbage.
Alpine SIRALP2C Sirius Tuner (Lifetime)
Alpine CHA-S634 CD Changer
Modified 12 volt Apple TV
Alpine MRV-1507 X 2 - subs
Alpine MRV-1505 X 2 fronts
Sony XM2100G (Vintage ES Series) rear
Realm LS6C - front doors
Realm LS5C - rear side panels
AVI SL250 Subwoofers in custom ported box designed by AVI founder Howard Doctor tuned to 29 Hz
AVI Tweeters - A pillars
Compustar alarm/remote start with remote windows, custom 225 Amp alternator.
