OS and Software > All Things Macintosh > [iPhone] Bigger Fail Than Maps ...

reply to Count Zero

Re: [iPhone] Bigger Fail Than Maps ...

Listen haven't not heard those two together I cannot definitively say what they sound like.

HOWEVER

Full quality audio will always be better than re-compressed audio and from what I could tell about the devices from the tech specs published online they're sending the audio over A2DP probably re-compressing to a 128kbps audio stream which (1) further degrades the quality of your original media & (2) consumes battery power to do unless you're plugged in - and then you might as well just stream the audio over your USB connection.

Granted cars aren't the best audio platforms in general but I have a 2010 Subaru Outback with the 440W Harmon Kardon stereo with a parametric EQ. I tuned the stereo using pink noise and some settings I found online and it's much better now than when I first got it - but when I drive I notice a significant difference in the clarity and the accuracy of the music between BT and USB. It may be that I listen to a lot of jazz and indie music where that is more noticeable but this is just an example of why I think saying "you can just stream it on bluetooth" is not as good.

reply to Count Zero

Re: [iPhone] Bigger Fail Than Maps ...

reply to Anon

Bingo. It's great to just get in the car, forget I even have my phone in my pocket, and just switch tracks using the radio controls.

I have thousands of tracks, I need playlist controls and I haven't seen an OEM automaker BT system that gives you that kind of control from the head unit. My 5-series can index through tracks using BT for example, but I don't have access to playlists on my Galaxy player. The handsfree BT doesn't integrate for voice control of the Galaxy player (so I can't just call for a playlist). I don't know if that is a byproduct of Samsung abandoning the player to Gingerbread the day it came out or what. It basically makes it a giant CD player with a gazillion tracks which is pretty worthless. The iPod control mimics the screen of the iPod including album art.

Hmm... As much as it pains me to say it (not a Ford man), Ford might have the best OEM BT on the market. I wouldn't know, though; I don't usually keep an OEM stereo for long.

I never have a car that a non-OEM head unit would look decent in.

reply to BronsCon
while that's theoretically possible - it isn't actually utilized in any real world applications I've seen.

Light travel is theoretically possible -- no one uses it. See the similarity there?

reply to skeechan
My wife's 2012 IS 350C can do it over BT from her iPhone - a first in our experience too!

reply to Count Zero

reply to BronsCon
My car can do that over USB or BT from the steering wheel.

But on long drives I get annoyed at the lower quality of BT. I guess I consider myself something of an audiophile and if I'm going to pay for high end stereo equipment I don't see a point in feeding it lower quality audio to play.

reply to BronsCon
Again, show me a consumer device that actually plays FULL QUALITY audio over bluetooth.

Seriously? I looked through the entire manual to see where it would validate your claim and could not find it (see several posts above). Again - your player uses A2DP and that typically re-compresses audio to 128kbps or less for compatibility. Since ALL of my files are 256kbps AAC or higher then I would expect your player to degrade the quality. Just because BT is theoretically capable of higher data rates DOES NOT mean that they are actually used for consumer applications. You seem to be unable or unwilling to accept that fact.

My ears tell me something different than your perusal of the manual. You can keep arguing but I don't see a point.

EDIT: In fact, the A2DP spec tells me something different than your interpretation of the manual.

See here: »en.wikipedia.org/wiki/Bluetooth_···8A2DP.29

Advanced Audio Distribution Profile (A2DP)

This profile defines how high quality audio (stereo or mono) can be streamed from one device to another over a Bluetooth connection. For example, music can be streamed from a mobile phone, to a wireless headset, hearing aid & cochlear implant streamer, car audio, or from a laptop/desktop to a wireless headset.

A2DP was initially used in conjunction with an intermediate Bluetooth transceiver that connects to a standard audio output jack, encodes the incoming audio to a Bluetooth-friendly format, and sends the signal wirelessly to Bluetooth headphones that decode and play the audio. Bluetooth headphones, especially the more advanced models, often come with a microphone and support for the Headset (HSP), Hands-Free (HFP) and Audio/Video Remote Control (AVRCP) profiles.

A2DP is designed to transfer a uni-directional 2-channel stereo audio stream, like music from an MP3 player, to a headset or car radio.[1] This profile relies on AVDTP and GAVDP. It includes mandatory support for the low-complexity SBC codec (not to be confused with Bluetooth's voice-signal codecs such as CVSDM), and supports optionally: MPEG-1, MPEG-2, MPEG-4, AAC, and ATRAC, and is extensible to support manufacturer-defined codecs, such as apt-X. Some Bluetooth stacks enforce the SCMS-T digital rights management (DRM) scheme. In these cases, it is impossible to connect certain A2DP headphones for high quality audio.

-- Peace.

reply to Count Zero
I think the problem comes down to Apple not supporting MP3 in their A2DP implementation. I suspect that's more popular in bluetooth receivers/speakers than AAC, although they'd all be better off supporting AAC. If the receiving device does not support AAC (which iOS resamples to 132kbps no VBR), then it falls back to SBC - the base compression that all A2DP devices must support, which sounds like shit. All other codecs are optional.

So if your car supports the AAC codec over A2DP, you'll get pretty decent sound quality. 132kbps AAC is roughly equivalent to 256kbps MP3, imo. If it doesn't, you might as well use an FM transmitter hooked up to the audio out.

Source: »developer.apple.com/hardwaredriv···ines.pdf
--
University of Southern California - Fight On!

reply to BronsCon
Nice wikipedia quote. That means IT CAN but does not enforce the support for all of those profiles except SBC (low quality profile).

--PEACE

reply to Thinkdiff
That may well be part of my problem with A2DP but I find very limited information out there about what formats different devices support over BT/A2DP. Also if you have a significant amount of music in ALAC then no BT profile will support the playback of that and it will always be re-converted to something else of lower quality.