[Viffermike]

Originally Posted by Redbeemer

I am still doubtful of the HU downsampling USB audio or especially CD's during playback. For one, most commercial DAC chips that I know anything about will play at least 44.1/16bit audio which is the same as a Redbook CD. Secondly, even if the HU maker wanted to cheap out and only play compressed audio, they would still have to use a DAC chip which converted from digital to analog at a 44.1/16bit rate, since all of the commercial sources for mp3 tracks, (iTunes, Amazon, etc.) encode them at the standard CD sampling frequency and bit rate (44.1/16 bit). I still fail to see any real "gain" for the manufacturer by downsampling audio files. What is the real difference in perceived quality between playing a CD at full resolution on a "poor quality" system and playing the same CD, but downsampling the music before playing it on a "poor system". The only area where the downsampling makes any sense is in the storage of files on the limited hard drive space available to archive music in the HU. That is the same reason that iPods (when they first came out) would only play back lossy files; they simply didn't have the storage space for very many songs, especially if they were stored in a lossless format. I guess we will never know for certain, because we both know that BMW/Harman would never admit to doing this even if it were true. Personally, I find the Harman system adequate for my needs since I play my car "radio" at fairly low levels so I can hear approaching traffic, car horns, railroad crossing signals, etc.

Keep in mind that a selling point of those commercial DACs that we can know anything about is its sampling and rate abilities. If those abilities aren't good -- or, worse, don't meet a typical current standard -- then the DAC's specs usually aren't mentioned. Hell: the DAC itself usually isn't mentioned in those situations!

My point is that BMW has more to gain than customers to lose via downsampling the programming fed digitally to the HU. Think about it: compression typically cuts off the very bottom and very top of the audible frequency range, as well as certain depth details (depending on the algorithm). The OEM system's drivers already can't reproduce highs or lows well at all -- and since the system is also underpowered, cutting those frequencies out via downsampling prevents unknowing customers from blowing the speakers because of bass' need for substantially more power at volume, as well as treble's need for clear, precise, stiff, highly efficient driver assemblies (which the OEM full-range drivers, either Hi-Fi or HK, are decidedly not).

Installing drivers that can handle the full audible spectrum properly reveals the OEM setup's deficiencies. Such drivers allow us to hear the frequencies higher-resolution audio delivers. This is fact, and has been demonstrated time and time again. What hasn't been demonstrated much until recently is how much of a difference a known lossless digital source, fed to the HU as an analog signal and amplified without the OEM DSP -- another deficiency-masking measure taken by BMW in the OEM setup -- makes in audible resolution and quality.

You may not be convinced, but I am. Logically (pun semi-intended), it makes total sense to design the OEM 2-series systems to downsample because of perceived quality vs. actual quality.

[Grave]

Originally Posted by Viffermike

The USB current issue is a legitimate one, since it's already been proven by other posters in other posts that the one provided doesn't charge very quickly -- and doesn't have the amperage to charge at all when too much is running (apps, etc.) on an attached device. I'd estimate that it feeds between .5 and 1 amp to any device plugged into it -- not much at all.

Many discussions about flac obsolescence or downsampling

The BMW notice said that HU can handle 4 usb device and a max of 40 000 files so you really can play large collection of CD.

What format ? Wav ? very large files and no tags possibility is'nt a good idea.

There are many other lossless : AIFF for Pears that says "APPLE uber Alles" and buy their products or "Free Formats" as WV, APE and FLAC

In fact OEM HU don't read WV or APE so choose AIFF, FLAC or crappy MP3.

What device ? HDD ? Yes if you use one with low charge such as a SSD.

You only need to formate your SSD in FAT32. I have my car for five months and use a 512 GB mSATA SSD in a USB3 enclosureof less than three inchs.

I can't fill it because most of my albums were in APE format but i have about 1200 albums and 400GB in use.

First connection was slow but now as i only add or change few albums, no more latence.

I replaced all speakers, use a Match DSP amp (as Bimmertech's one) and an old Alpine for the subs. Ajustements were done with pink nose and a Berhinger microphone.

That was my 2 cents...

[Viffermike]

Originally Posted by Grave

Many discussions about flac obsolescence or downsampling

The BMW notice said that HU can handle 4 usb device and a max of 40 000 files so you really can play large collection of CD.

What format ? Wav ? very large files and no tags possibility is'nt a good idea.

There are many other lossless : AIFF for Pears that says "APPLE uber Alles" and buy their products or "Free Formats" as WV, APE and FLAC

In fact OEM HU don't read WV or APE so choose AIFF, FLAC or crappy MP3.

What device ? HDD ? Yes if you use one with low charge such as a SSD.

You only need to formate your SSD in FAT32. I have my car for five months and use a 512 GB mSATA SSD in a USB3 enclosureof less than three inchs.

I can't fill it because most of my albums were in APE format but i have about 1200 albums and 400GB in use.

First connection was slow but now as i only add or change few albums, no more latence.

I replaced all speakers, use a Match DSP amp (as Bimmertech's one) and an old Alpine for the subs. Ajustements were done with pink nose and a Berhinger microphone.

That was my 2 cents...

Dude ... please read the entire thread before jacking it with grammar-delinquent techno-drivel like this.

The central point has been addressed: the HU's digital music file processing is not acceptable for higher-quality files. The only recourse is an outboard DMP fed to the system as an analog signal. Good luck doing that with just SSD storage.

[Grave]

Originally Posted by Viffermike

The central point has been addressed: the HU's digital music file processing is not acceptable for higher-quality files.

The central point ?

Only your assertions but it's true you wrote more than half reply of the thread

[Viffermike]

Originally Posted by Grave

The central point ?

Only your assertions but it's true you wrote more than half reply of the thread

I have half the responses because I care about sound quality, understand what it actually is, and have issues with those who think they do but actually don't within the context of the audio platform being discussed.

The OP's original questions:

"What is the best way to do this that would result in the highest possible audio quality? I'm assuming that the key is to create FLAC lossless files. Yes? And if so, what device would be best for the highest quality? An external player connected by USB? Any recommendations on how to do this and what equipment to use would be appreciated. Flat sound a priority."

My answers all directly relate to the OP's concerns.

[bobbeckster]

Hear is my .02. I am an old guy with old ears and the H-K system. I drag MP3 and Flac files onto a 64 Gig thumb drive. Typically I have a folder with the audio files and a jpeg for album art. My 2016 car lets me browse the root directory to select music and I think it works well. I have experimented with managing my file with J.River Media Center and I can "equalize" the files for my car. I am also experimenting with playlists in the root directory but no concrete advice yet. I get the album art on my screen.

[selmeralto]

Have just taken delivery of my new M235i. Wonderful car.

But ... just writing to confirm, speaking as a longtime audiophile, the HK system is as bad as I feared. Terrible factory equalization configuration, wonky soundstage, etc. I had better sound with old Alpine systems years ago.

Listened to and burned to the car's system a CD. Not a happy experience.

With the help of the many on the forum who have contributed to the HK discussion I'll start making changes, starting with what I can do without spending gobs of money: disconnecting the center speaker, adding the ASD removal harness, and listening with lossless files from a USB via audio input.

If I'm still disappointed I'll consider swapping out the front door speakers.

I'm trying to avoid buying a new amp after spending $850 on the HK system.

Thanks to all who have suggested ways to improve the sound.

No thanks to BMW on the "premium" sound system.