UncleFunkle

I still think, even if you pipe an unfiltered live band directly to the car's audio system, the limfac is the audio system. Bose blows. you can play a a pure anolog signal into a Kraco stereo and it will still sound like a Kraco stereo

perdido34

You're wrong about "going through USB is digital." The only way to get a digital music signal out of an iPhone is through a device like the (discontinued) Wadia i71i:
http://www.wadia.com/ContentsFiles/W...1i_Bro.pdf.pdf. Add to that an external DAC.

I don't know of any car devices that do this. A manufacturer has to buy a license from Apple to get digital output through the iPhone connector. What the Bose "sees" through the USB port is the filelist that exists on the phone, but what it "hears" is the analog output of the iPhone's DAC.

If you want to play music files with higher resolution than CD quality (16/44.1), you can use an app such as VLC for iOS, but the output still comes out no better than CD quality through the headphone jack, the iPod/USB interface, or Bluetooth.

As for Bluetooth, the DAC in the phone converts the digital source to analog, then the phone puts the analog signal into binary form before sending it over Bluetooth to the receiver in the car.



As for Bluetooth, the sound quality is compromised regardless of the source

Darth Kinetic

what settings did you use to retain CD quality during a Rip to MP3?

TVPostSound

iTrader: (9)

Dont rip to MP3, rip the CD in its raw form. 44.1K16 bit, and make it WAV.

MP3 is a compression codec.

Darth Kinetic

I was sure I just read that our Infiniti system will not read a wav file...?

perdido34

OK, why don't you try playing a WAV file from a thumb drive through your car's Bose system and report back? On my 2013 G, the WAV file doesn't even show up on the car's screen if it's on a thumb drive. Please let us all know once you have tried this, and if you get a different result than I did (and also tell us what year your car is.

Concerning your statement that mp3 files are compressed, yes you're right. I would suggest that someone take the same song, preferably one that was recorded some years ago before mastering engineers compressed the dynamic range of everything to make it sound louder, and rip this song to a WAV file and also to a 320 kbps mp3 file. Name them differently so you know which is which. Copy both files onto your phone and play them through the car's Bose system (phones can play WAV files). Or better yet, close your eyes and do a blind test with someone else at the controls. Run a number of iterations so you can see how far away you get from chance probability (50%).

I would guess that since most people can't even reliably distinguish between these files on a decent home system, that the overwhelming majority of listeners won't be able to figure out which one is the mp3 file on the compromised audio of a decent car system like the Bose.

TVPostSound

iTrader: (9)

WOW, Im burning my EE right now as Im reading your wisdom!!
NOT.

Binary is digital, why would Apple convert to analog then convert back to digital??


Ill do you one better, take an iPhone 5 (8 pin lightning port) and plug it in
to the USB port of your car. Lightning DOES NOT support analog audio.
Im playing through with no issues, these are uncompressed 44.1 16 bit.
Its digital. Bose handles uncompressed audio at CD bandwidth.

Before you go on, the lightning to 30 pin adapter has a DAC in it, Im NOT using one, its
iPhone lightning port to USB.

TVPostSound

iTrader: (9)

MP3 files have digital compression to save space, which is different from dynamic compression.
I stopped mixing music when my songs were over mastered.

TVPostSound

iTrader: (9)

OK, IM tired of correcting other's bad information.

Im done here!!

Darth Kinetic

oop: .

perdido34

While you're done here, I wanted to post some actual information.

I took a USB thumb drive (formatted as FAT-32) and copied three files onto it:
One was a 24 bit/96 kHz (hi-res) WAV file. The other two were rips from a CD, one as a WAV, the other as a 320 kpbs mp3 file.

So these were the only three files on the USB drive:
24-96.WAV
WAV-version.wav
mp3-version.mp3

I plugged the drive into the car's USB port (2013 G with Bose/nav) and the audio started to play "Track 1 of 1." When I chose Track List from the menu, the only thing that showed up was mp3-version.mp3.

Conclusions: As I have said several times, and contrary to that person who claimed to have mastered recordings, the audio system in this car will NOT play either hi-res or CD-quality WAV files from a USB thumb drive. It will only recognize and play mp3 files from a thumb drive. So in response to the person who claimed you can get great sound from the Bose system by playing hi-res files on a thumb drive, well I don't think so.
If anyone actually tries this for themselves and gets a different result, let us know!


Yes, the car's system will play CD-quality files from an iPhone, but Apple converts them to analog as they come out of the phone. Why Apple does this is another question, but it's a fact. This has been the way all iPhone models work: "Astute readers may have noticed that the Lightning connector does not support analog audio-out, but the 30-pin adapters do. That’s because hidden away inside each 30-pin adapter is a digital-to-analog converter (DAC) that converts the Lightning connector’s digital audio signal to an analog version. (The inclusion of a DAC explains at least part of the price of the adapters.)" Lightning: the iPhone's new connector | Macworld


Yes, you can play hi-res files on an iPhone with a player that can recognize them (e.g., VLC for iOS), but they are down-res'd to 16/44.1 before getting transmitted digitally via Bluetooth or getting converted to analog through the headphone jack:

"Apps such as VLC for iOS and Onkyo HF Player can play high-resolution files, but there’s a catch: What you can hear on your iOS device is limited by its headphone jack, which is capable of reproducing only CD quality (16-bit, 44.1kHz). Even AirPlay is limited to CD-quality audio (although it can handle 24-bit and 48kHz for video). To unleash the fidelity of high-resolution audio files through your iOS device, you need a specially designed external digital-to-analog converter. Unfortunately, few DACs are designed to work with iOS devices." High fidelity: How to get lossless and high-res audio on iOS devices | Macworld

Absinthe

Perhaps you didn't read my response correctly. If you don't educate the listener what high fidelity and quality is, hey have no indication that what there listening to is quality or not. If you have nothing to compare one system to, you have no basis for any conclusion; you can expect the same results if you don't know what to compare against the two systems. If your idea of high fidelity is Bose, you really have no argument point as most of the industry will disagree with you. However, if you like it, go with it

As for recording media having no impact on audio quality Id say your dead wrong. Magnetic tape is severely limited in fidelity by how fast the tape travels over the head, the purity of the iron oxide and the saturation level of the tape. LP's have the advantage of speed past the needle but lack the ability to capture extensive dynamic range due to the nature of the groove width and the physical ability of the average phono needle to track the more energetic grooves. The cannon on a live Telarc recording of the 1812 overture are a prime example of this. Aside from this the main thrust of my response was the fact that the majority of America thinks the MP3 audio on their iPod is high fidelity which of course a fantasy fueled mainly by the ignorance of the listener

I never claimed that anything playing MP3 (Car radio, iPod or whatever) would shine. XM while slightly better also does not shine

Oh, and I drove three hours a day with a bone stock Bose SOW system for six months; played uncompressed audio exclusively and no, it didn't shine either.

Absinthe

There have been several high end audio magazines that have done tests similar to what you propose and as you suspected, only a minority of listeners could tell the difference. However, the real test you probably want to run (although wildly impractical) is take the same files and play them through a higher end system and the Bose SOW and see which one sounds better to you

Darth Kinetic

Evil...did you end up making some changes yet?

DHS803

It can yes but I'd try a sub in the trunk. I have a powered sub and it sounds really good. Also, if you have the coin you should buy components for the doors. I recently replaced my door speakers with 2-ways and even though my woofer size dropped from 10 to 6.5 I haven't noticed any change in bass, the sound is much more accurate and the tweeter placed in the midrange location sounds fantastic. If you have the budget check out the Image Dynamics subs referenced in the forums. Apparently those are incredible. Too much $ for me right now.

Make sure you Dynamat the rear deck for sure and also the doors at least around the woofers if nothing else.