[ProAudio] Car audio systems

[Paul Kraus]

Hi Steve,

	I have observed something similar, but with very different details. More below.

> On Dec 21, 2022, at 7:47 PM, steve mastercraftrecordings.com via ProAudio <proaudio at bach.pgm.com> wrote:
> 
> 
> I’m digging into car audio systems and why many are so *enjoyable* to listen to. I’m not saying they are accurate. Far from it. But somehow, if you can turn off your critical listening skills, it can be fun to listen in the car. And I’m simply curious about why. I’m sure some of this is psychological, (reduction of expectations) but there is likely more to it than that. 

My limited experience is with Audi and Porsche. Audi using B&O and Porsche using Bose. The specifics are:

2008 Porsche Cayenne (SUV)
2010 Audi A4 (sedan)
2015 Porsche Cayenne (SUV)
2018 Audi Q5 (SUV)

The Audi/B&O systems are much more sophisticated than the Porsche/Bose.

It sounds like the Porsche/Bose is basic DSP for EQ on each speaker and they achieve consistent sound.

The sound of the Audi/B&O is *much* more processed, but not in a bad way. They are playing with imaging to a much higher degree. You even have options to ’tune’ the sound for the driver or everyone. I leave the ’surround’ effects turned off as I find that is just too much. I also note that the announcements (navigation) are tuned very differently than music (as they should be).

I agree that the sound is not accurate, but it is fun to listen to (even the older 2010). 

<snip>

> In particular, I find it hard to believe there is no dynamic processing being done. It sure *feels* like it although it’s not blatant - no *obvious* compression artifacts — at least in my car. 

The Audi/B&O system is absolutely doing dynamic processing (and reducing peak-to-average ratios as you turn the volume up to achieve higher perceived loudness without clipping). It is also doing a bunch of ‘image steering’ for lack of a better term. Those systems have a solid center image… from every seat in the car. I was truly astonished when I heard the sound from the backseat and it was almost as good as the front seat. Levels and imaging was very closely matched.

> Also, seems like there must be some matrixing employed as well. About all I’ve discovered so far is that there is DSP EQ on each speaker and DSP to time the arrival of sound from each speaker (although I have found nothing on how that is worked out for driver vs passenger front vs passenger rear, etc.) There must be more than that.

Yes, see comments above about image steering. 

> Can anyone point me to resources or fill me in?

I will bet that anyone developing these systems with the vehicle manufacturers considers them very serious trade secrets and will not be willing to share what they are doing. If you do find someone willing to share what they are doing, please share with the group.

—
Paul Kraus