MikeWI

What are the Bang and Olufsen digital analog converter (DAC) characteristics?


I just purchased a 2017 A4 yesterday and wondered what FLAC files it could handle. I haven't tested many yet.

I have been increasingly downloading higher resolution formats (in FLAC) from Pono and HDTracks. A common ripping "standard" is 16 bit depth and 44100 Hz sample rate. I have many FLAC files at 24 / 48K, 24 / 192K, etc. up to 24 / 352K. In a prior (DDX5901HD w/ 24bit DAC) head unit the higher bit rate files would have problems playing.

That head unit had "Technology Bluetooth Ver3.0+EDR" but I can't tell BT version for 2017 A4.

Thanks. New here.

Mike

MikeWI

Links:

A4 - Bang & Olufsen 3D Sound System
A4 - Bang & Olufsen

Specifications
Speakers
19 speakers

Amplifier
16 amplifier channels
755 watt output power
Class D technology

Digital Signal Processing (DSP)
Class D amplifier
MOST150
Microphone inputs

Sound Features
Vehicle Noise Compensation (Road EQ)
Digital Transmission Content Protection (DTCP)
Fraunhofer Symphoria® 3D algorithm
5.1 multichannel support
Diverse sound setting options (front/rear/all)

Design
‘Dynamic Line’ design
Anodized aluminium finish
Harmonic integration in the A4 interior

MikeWI

Bang and Olufsen Links

Car Audio - Bang & Olufsen
Audi - Bang & Olufsen
A4 - Bang & Olufsen


LowBeats | Neuer Audi A4 mit B&O-3D-Klang [9/10/15, German]
Erster Check: neuer Audi A4 mit B&O-3D-Klang ? LowBeats

LowBeats | 3D-Hörtest im neuen Audi A4 [..., German]
3D-Hörtest im neuen Audi A4 2.0 TFSI ultra - LowBeats

Bang & Olufsen announces 5.1 surround system for Audi R8 [3/4/15]
Bang & Olufsen announces 5.1 surround system for Audi R8 | What Hi-Fi?

The all-new Audi A4 - Bang & Olufsen 3D sound system [1/13/16 Video]

Bang & Olufsen Premium Sound System... Are you kidding me? [4/18/13]
Bang & Olufsen Premium Sound System... Are you kidding me? [Archive] - Audizine Forums

MikeWI

I haven't gotten an answer on DAC type or specs yet.

However, I tried out these test FLAC files (randomly selected for testing).

BR / SR / Track

Worked
16 / 44.1 / Iggy Pop - Lust for Life
24 / 44.1 / Paper Gods (feat. Mr Hudson)
24 / 48 / Love Used To Be
24 / 96 / Skyfall
24 / 192 / Main Title and The Attack on the Jaku Village

Didn't work
24 / 352.8 / A Place In The Choir - "file not readable" message
1 / 5454.48 / A Place In The Choir (DSD, dsf file) - title not recognized


BR = bit rate
SR = sample rate


I will try out a 24 / 176 FLAC file and edit.
But this would suggest a 24/192 DAC capable DAC. It could be 24 or (less likely) 32 bit.


Mike

mej16489

FYI, just because a system is capable of playing a file which is 24/192 doesn't in any way guarantee that its a 24/192 DAC. Realtime downsampling to a lower sampling rate to a physical DAC is a trivial computation. Which is why you will want to know the capabilities of the physical DAC for the most optimal solution.

MikeWI

Thank you for commenting.
You bring up good points.
I know JRiver detects "too high" for DAC and downsamples, but I wasn't aware that was common in car audio. It didn't work in my prior car with a new aftermarket audio system.

And arguing against that is that the 24 / 352.8 was detected but not downsampled. If the software was detecting sample rate and down sampling the others, one would expect this to also be downsampled.

However, your points are good ones and suggest that this information should be transparently made available.

Mike

MikeWI

Bang & Olufsen 3D Sound System for the new Audi A4 (PPT -> PDF)

MikeWI

(Is there a way to edit prior posts? I'm used to that in other Forum software -- eg AVS)

I tried this FLAC file:
24 / 176.4 / Michael Jackson - Wanna Be Startin' Somethin'

And it worked.

Summary:

BD / SR / Track

Worked
16 / 44.1 / Iggy Pop - Lust for Life
24 / 44.1 / Duran Duran - Paper Gods (feat. Mr Hudson)
24 / 48 / Love Used To Be
24 / 96 / Skyfall
24 / 176.4 / Michael Jackson - Wanna Be Startin' Somethin'
24 / 192 / Main Title and The Attack on the Jaku Village

Didn't work
24 / 352.8 / A Place In The Choir - "file not readable" message
1 / 5454.48 / A Place In The Choir (DSD, dsf file) - title not recognized


BD = bit depth
SR = sample rate


Knowing that almost all of my FLAC files work (and don't need to be converted to 16/44.1 FLAC or MP3) is useful.

This doesn't characterize the DAC and if it is 5.1 channel or 2 channel etc.


Mike

*EDIT*
Apparently I can edit now. Maybe I just need to satisfy a time and/or post # threshold?

mej16489

Its entirely within the realm of possibility that some rate combinations can be down-sampled on the fly and others cannot because it would be considered too much loss by the developer.

Unfortunately, lack of transparency in the digital realm is not the least bit uncommon in Audio/Video circles. Pretty much the only realm you can somewhat count on the information provided is in the commercial realm for studios.

Are you familiar with avsforum.com? You might have some luck over there...lots of industry insiders frequent that forum.

MikeWI

Good comments.
1) Glad the files work, even if not sure if downsampled
2) Still looking for info

I am on AVS. Just seemed like a very niche question.
I was surprised this wasn't in product literature (even if buried in manual) or in training slides (see prior post). Especially since Audi compares vs other products.

Audi otherwise seems very tech oriented and should be well aware that at least a subset of people care about these things.

Mike