Bypass iPod Sound Output?

[ipodder828]

As of now, I am using a Blitzsafe adaptor running from the line-out on my iPod to RCAs on the back of my Eclipse deck. Although the sound quality is definitely better than the mini-to-RCA cable I was using previously, it still does not sound as good as when I play the same MP3s on my iPod, but burned to a CD (I get much better bass, more clarity, higher volumes without distortoin, etc...) This leads me to believe that the problem is not with the cable I am using, the bitrate, etc... but with the sound output of the iPod itself. Do the specialty cables that audio manufacturers like Clarion, Eclipse, Alpine, etc... actually bypass this output and "stream" directly to the deck, so that the deck itself is actually playing the music file for the best sound quality? Sorry about the wordiness, but hopefully you guys can understand what I am trying to figure out here.
thanks

[bobb-mini]

If u can find a HU that has a digital iPod connection (USB plug is a good sign).

It's my opinion that iPod D-A converter does not perform as good as your run-of-the-mill HUs. Most people don't notice this 'cuz their cars don't have a 200 watts/10 speakers/10" sub setup.

If I want superb music, I still resort to burning CD and play that in my 5 years old AIWA HU. The separation, the authority, the clear bass. Ohhhhh Ma-ma.

Fortunately these days, I mostly listen to podcasts, and just the occasional music, so quality not so important.

[ipodder828]

Yeah, I have a pretty pricey setup - Eclipse HU, JL Audio fronts/Memphis backs, Memphis sub, and Memphis Belle amp...so I can really notice the difference when I use my iPod. Unfortunately, my HU just has RCAs and no digital iPod connection...I may invest in one of these decks in the future...wish I had known about this when I bough mine...its only a year old!

[bobb-mini]

Don't feel bad, I am not sure a digital iPod interface is available yet, but then I haven't looked lately.

Anybody reading this and you have a nice setup (nice=separate Amps and subwoofer, definitely after market). At least get a HU capable of DVD double layer, so u can have 8 Gigs of your critical tunes on a single DVD and play those tunes at their full glory.

[ipodder828]

Sorry to bring this thread back from the dead, but I noticed that that Eclipse now sells an iPod interface that will work with my deck (see here (http://www.eclipse-web.com/acce/ipc106.html)). How exactly does this work? Will it pass on a pure digital signal to my deck, or will it still be using the iPod's D-A converter?

[bobb-mini]

U mean u look alllllll the way back and didn't just look a few threads down? do, on the same page, it's been discussed. I dunn know about the Eclipse, but Alphine and Pionner do.

[ipodder828]

I'm not seeing anything about how exactly the signal is passed on from the iPod to the deck. If there is a direct connection, can it be assumed that it is passing on the signal untouched? The device I am referring to has an external box-type adapter, so it is a bit different from the Alpine or Pioneer.

[bobb-mini]

No-no-no-no. A DIRECT, DIGITAL connection is simply a USB plug, no adapter, no nuthing. The said head(s) has the necessary software to understand the "iTunes structure" and reads the iPod like normal external drive AND THEN run its own software (in the head) to extra the information.

[ipodder828]

Okay, so with an external adapter like this, is the DAC inside of the adapter? If so, is the DAC inside of the adapter as good as the DAC inside of the head unit?

[Uncle Rico]

I believe that all current iPod adapters are simply using the analog line-out from the iPod. Alpine's older solution also had a box like this, but all the box does is interface the controls from the head unit to the iPod and pass along audio. The head unit essentially sees the adapter as a CD changer. Even the newer solutions, like Alpine's current adapter (cord directly from the head unit to the iPod) still use the iPod's line out. An easy way to test whether your adapter is decoding the files itself is to put the iPod in a standard dock and plug the cable into the dock. The dock splits off the line out signal to the mini jack, so if you can control the iPod through the head unit but get no sound, then your adapter is using the iPod's line out (hopefully that made sense... it sounded good in my head!)

I think the reason why you never see any adapters that take the data directly from the iPod and decode internally is due to the fact that iPod uses some proprietary formats. Sure, MP3s and AACs you ripped from your own CDs would work ok, but how would the head unit decode FairPlay encrypted files purchased from iTunes? Or Apple Lossless, if you choose to encode your music that way. It is a closed-source format and currently Apple does not license it to anyone that I know of. There would be a lot of ####ed off customers if they could only play some of the music on their iPod.

There is hope though. Alpine has a new head unit coming out in April (they say) that is designed specifically around iPod functionality. Apple actually helped them design this beast. I am led to believe that this new head unit does actually decode the files internally. Link: http://www.alpine-usa.com/US-en/products/product.php?model=iDA-X001 Here is my reasoning: First and foremost, this unit displays album art attached to your music files. There is no other car adapter or even home dock that can do this. If you get into the nitty-gritty specifications and have a look at the dock connector pin-outs, there is definitely no dedicated signal for album art. Secondly, in the pictures the head unit is shown distinguishing between songs, podcasts, audiobooks, etc. No other car adapter I've seen does this. Some of them will let you listen to these, but they are all lumped in your music library. Finally, in the specs for this unit, Alpine specifically states that there is support for Apple Lossless and AAC. This would be implied if it were simply receiving an analog line out signal from the iPod. Also, before 2007 no Alpine head units supported AAC (burned on a CD) but all of the new units do. Oh, and I almost forgot, in the features, Alpine also talks up there 24 bit DAC. And since the HU was co-developed with Apple, I assume FairPlay support would be built in.

If this new unit really delivers everything it claims, I'll be purchasing one right away. I completely empathize with you regarding the sound quality of current adapters. I've got a decent setup in my car that sounds great with CDs and pretty good with the iPod, but I am picky and could definitely stand to get a little better quality out of the iPod. Especially considering all of my music is in Apple Lossless. I just have to cringe whenever I see someone using an aux in minijack on their factory radio with the amplified headphone jack on their iPod... or, god forbid, and FM modulator!

Sorry for the long post, but I hope it was informative :D

[bobb-mini]

Okay, so with an external adapter like this, is the DAC inside of the adapter? If so, is the DAC inside of the adapter as good as the DAC inside of the head unit?
I said NO ADAPTER, am sorry that wasn't clear enuff. Hope Rico's post helps.

[ipodder828]

Rico, thanks for your post - it was very informative. Things are cleared up for me now. I will be very interested in the new Alpine unit when it is released.

[deezel629]

I too have a "system" in my car and have tried countless set-ups to get the sound out of my iPod that I get out of a CD. I've come to the realization that it isn't out there, at least not yet anyway. My current setup is I'm using the AUX output on the back of my HU(Pioneer). The mini plugs into a small dock connector adapter. Then that plugs into the bottom of the iPod. It sounds OK. The bass is what lacks. On some songs, the bass is non-existant. I found that if I halfway unplug the mini adapter that goes into the small dock connecter, I get a significant boost in bass. The downside of this is that while bass increases, treble decreases.

Thanks to Rico digging up the news about the Alpine HU coming in April, maybe this is the solution all of us have been looking for.

[ArcCoyote]

Pioneer has a HU out now that does this: DEH-P6900IB. I have the P5900IB, which has the usual type of iPod connection.

http://www.pioneerelectronics.com/pna/v3/pg/product/details/0,,2076_310069880_338818745,00.html

FYI, the USB interface doesn't read the filesystem, it probably uses something similar to DAAP over USB. Only newer iPods (nano, 5G, software v1.2+) can stream audio via USB.

[THX]

I believe that all current iPod adapters are simply using the analog line-out from the iPod. Alpine's older solution also had a box like this, but all the box does is interface the controls from the head unit to the iPod and pass along audio. The head unit essentially sees the adapter as a CD changer. Even the newer solutions, like Alpine's current adapter (cord directly from the head unit to the iPod) still use the iPod's line out. An easy way to test whether your adapter is decoding the files itself is to put the iPod in a standard dock and plug the cable into the dock. The dock splits off the line out signal to the mini jack, so if you can control the iPod through the head unit but get no sound, then your adapter is using the iPod's line out (hopefully that made sense... it sounded good in my head!)

I think the reason why you never see any adapters that take the data directly from the iPod and decode internally is due to the fact that iPod uses some proprietary formats. Sure, MP3s and AACs you ripped from your own CDs would work ok, but how would the head unit decode FairPlay encrypted files purchased from iTunes? Or Apple Lossless, if you choose to encode your music that way. It is a closed-source format and currently Apple does not license it to anyone that I know of. There would be a lot of ####ed off customers if they could only play some of the music on their iPod.

There is hope though. Alpine has a new head unit coming out in April (they say) that is designed specifically around iPod functionality. Apple actually helped them design this beast. I am led to believe that this new head unit does actually decode the files internally. Link: http://www.alpine-usa.com/US-en/products/product.php?model=iDA-X001 Here is my reasoning: First and foremost, this unit displays album art attached to your music files. There is no other car adapter or even home dock that can do this. If you get into the nitty-gritty specifications and have a look at the dock connector pin-outs, there is definitely no dedicated signal for album art. Secondly, in the pictures the head unit is shown distinguishing between songs, podcasts, audiobooks, etc. No other car adapter I've seen does this. Some of them will let you listen to these, but they are all lumped in your music library. Finally, in the specs for this unit, Alpine specifically states that there is support for Apple Lossless and AAC. This would be implied if it were simply receiving an analog line out signal from the iPod. Also, before 2007 no Alpine head units supported AAC (burned on a CD) but all of the new units do. Oh, and I almost forgot, in the features, Alpine also talks up there 24 bit DAC. And since the HU was co-developed with Apple, I assume FairPlay support would be built in.

If this new unit really delivers everything it claims, I'll be purchasing one right away. I completely empathize with you regarding the sound quality of current adapters. I've got a decent setup in my car that sounds great with CDs and pretty good with the iPod, but I am picky and could definitely stand to get a little better quality out of the iPod. Especially considering all of my music is in Apple Lossless. I just have to cringe whenever I see someone using an aux in minijack on their factory radio with the amplified headphone jack on their iPod... or, god forbid, and FM modulator!

Sorry for the long post, but I hope it was informative :D
Just bumping one of the best posts I've seen here :)

I know we're a minority, but us SQ freaks need our digital fix! ;)