Not that it helps or anything, but Alpines IDA decks bypass the iPod DAC in favor of the onboard (24 bit burr brown) - and charge/control the ipod - and have by far the best ipod interface ive seen in car audio. But they are not without their faults. Mainly, the preamp is ameasily 2v, and their EQ options are pretty much nill (bass/highs, fade/balance... some subwoofer options) - basically need to pay for a few other additions to bring them up to par, an external processor mainly. However since using them I have to say that even through cheapo factory speakers the difference was immediately audible - everything was clear with great definition. I can now pick out details in my car that I used to only be able to hear through my Sennheiser 380 Pros - which actually made me tear up the first time I listened to a few tracks off Pink Floyd's Pulse through them.

There is one other option that i recently discovered... Apple Digitial AV Adaptor gives a pure digital out via HDMI. Then, although it isn't cheap, its simply a matter of an HDMI to TosLink conversion. Did I mention that it wasn't cheap: Gefen? There is also the issue of powering the converter...

So in short, I'm going to stick with the Alpine IDAs and throw a processor in there to round out the controls of the HUs. Now if only there were a HU that took HDMI inputs...

Posting from work, so need this disclaimer:
"The views expressed here are mine and do not reflect the official opinion of my employer or the organization through which the Internet was accessed."

 

I completely forgot about the Alpine setups! I am no longer as unique a flower as I was hoping. Those are great links, though, gnesterenko! That Digital AV Adaptor looks especially interesting, has anyone used it for audio like that? Since I actually only need coax digital I was hoping that maybe there was a non-powered converting alternative but it looks like HDMI is lame and there are only really expensive powered alternatives. Still interesting though!

 

smh
that iLink server is pricey

 

Thank you for the great post joojoo2915. I wish more people would post like that. I especially like the links to the external sources.

I'm not familiar with all the "i-stuff", but is there any way to get digital audio to output over USB? And while we're on the topic, what about for Android phones? Is there an easy way to get USB out from Android phones to interface with something like a PCM2903b? (I'm interested in USB from phone to the PCM2903b which has S/PDIF output that could go to the car audio system).

 

is there any way to get digital audio to output over USB?

I worked at HeadRoom (headphones) for a while and at the time they made a DAC that accepted input from USB and had an S/PDIF output, so it is definitely possible. You had to use their special driver to get it to work, though. As gnesterenko pointed out there are a couple of Alpine decks that accept USB input as well. It seems like it should be completely feasible to get USB to Toslink working on Android phones/devices I am just not sure if anyone has. If you find anything please let me know. And I am going to talk to my EE friend about the PCM2903b. I know there was talk about one of the recent (or possibly to be released versions) of Android allowing the devices to act as a USB host. If that's the case and it can supply power to the chip via USB that would be a fantastic option.

 

"First off I want to acknowledge that I realize it is kind of ridiculous to connect your iPod digitally"

I have to disagree with you on this point. I've found a huge difference in SQ using the analog out from the iPod vs. digital into the P99. I guess it depends on the HU but there's no comparison on my system.

On the other hand: After spending some time tuning I can definitely hear a difference between the iPod with lossless and RedBook CDs. There's definitely an improvement in staging, top-end air and definition with the CD. Maybe that's because the P99 has a better transport than the iPod Classic I use or whatever, I definitely hear a difference. Same when comparing to the iPhone 4...

I use the iPod for convenience, it's nice to have a whole bunch of music available on demand. But for absolute SQ, it just doesn't cut it of you have a HU with a decent transport/DAC.

Just my $.02 worth,
Bill

 

I have to disagree with you on this point.

That is totally fair, if you have tested it both ways you have more experience in the matter than I do. I mean, the difference you perceive could potentially be biased by the fact that you expect it to sound better (unless you have actually done some blind tests) or due to different volume levels but really I wouldn't be surprised if you are completely correct and there is a perceptible difference. May I ask how you connected iPod classic digitally?

 

joojoo,

iPod/iPhone 4 are connected through the USB input to the P99. There's some discussion about that on bikinpunk's P99RS review thread. Lot less complicated than what you went through but your OP is definitely interesting. I never would have thought of using an Airport Express in the car.

Thanks for sharing.

Best,
Bill

 

There's some discussion about that on bikinpunk's P99RS review thread.

That is some really awesome analysis, thank you very much for linking that review for me!

In other news I have requested a IC sample from TI and I fully intend to see what can be done with digital out via USB from Android. If I (well, my friends and I) can make it work I will be sure to update this thread.

 

Some quick points.........

-Taking the digital signal out from a portable device is definitely not ridiculous and if done properly is indistinguishable from even the most expensive home digital source out there. That type of interface put the idevice into a MSD state which is essentially an external hard drive mode.

-Alpine bypasses the iDevice DAC BUT it does not send a digital stream all the way from the file origination to the DSP chip input in the head unit.
Which is what we all expect when we hear "it bypasses the DAC".

What they do is convert the digital stream at the head unit using a DAC, then that analog signal gets sent to a source selector which then sends the analog source chosen to an ADC for digitizing to be able to go into the head units Digital Signal Processor.

So in the end, you still go through the same number of conversions and there is also no reason the DAC in the head units usb input is any better then that of a quality iDevice.

See Erin's thread below for proof of this. You'll notice how the ipod source results are different then the CD source results for the new top of the line ina-w910. This can not be possible IF the usb interface stays digital all the way to the dsp input. The results would be nearly identical if only the digital source changed source (ie ipod usb versus internal CD transport). As they are in his pioneer p99 test of the ipod usb connection versus the internal CD. (Digital outputs ALWAYS measure the same in an RMAA test. These test don't take jitter into account but that doesn't matter anymore unless we are talking about a CD player from 1985. So if they measure the same in that test, then the digital outputs will sound the same.)

http://www.diymobileaudio.com/forum/bikinpunks-product-review-forum/108165-alpine-ina-w910-vs-alpine-iva-w505.html

Granted this is an assumption that ALL Alpines do this, but if the newest top of the line unit works like this them its safe to say that a IDA $150 USB unit does as well.

-Airplay is good except that you have to enable it each time you get in the car since it defaults to internal speakers once you leave the wifi network (ie APE). Also when using an iphone you loose all functionality that depends on 3G for data like navigation and maps and stuff. Since naturally you are connecting to a router (ie APE) which itself does not have the internet connected to it for those data task. I forget what other points, I haven't looked at the option in a while. There is a 5 volt mod out there which allow you to skip the inverter for a much more stable dc to dc converter of your choice. I can provide the link if anyone is interested.

-I use a Pure i-20 digital ipod dock which bypasses the DAC like the other units mentioned. It functions very well and is bug free up to now. It syncs and boots instantly and is only $100. It runs of 7.5 volts DC so a good quality dc to dc converter should be perfect for it in a car, especially when using a digital out which would not need a super clean converter. This one from powerstream.com looks good and is pretty affordable - PST-DC292 . You might need different tip for it then the one provided though, I haven't measured to see if the one that comes with it is compatible.

The i-20 also has a clean 2 volts analog output for anyone interested.

http://www.diymobileaudio.com/forum/member-reviews-product-comparisons/109034-pure-i-20-digital-ipod-dock-analog-output-rmaa-measurements.html

 

-Alpine bypasses the iDevice DAC BUT it does not send a digital stream all the way from the file origination to the DSP chip input in the head unit.
Which is what we all expect when we hear "it bypasses the DAC".

What they do is convert the digital stream at the head unit using a DAC, then that analog signal gets sent to a source selector which then sends the analog source chosen to an ADC for digitizing to be able to go into the head units Digital Signal Processor.

So in the end, you still go through the same number of conversions and there is also no reason the DAC in the head units usb input is any better then that of a quality iDevice.

Finally SOMEONE who can give a legible explanation of Alpine's "DAC Bypass" to me. Makes sense now that you mention it, as opposed to DEX-P99RS method. Just to check that I understood you correctly, there is still Digital to Analog and then again Analog to Digital conversion going on, except that its all going on inside the head unit instead of using the iPod hardware? As opposed to DEX-P99RS that connects the the iDevice to the DSP and then DAC for final amplification without the back and forth conversion?

All that said, there is a slight difference in what we're talking about here. Mainly price (a factor of 10 no less). The DEX-P99RS is an allout audiophile head unit, and while I would love to own one, its hard to justify spending 25% of my cars total value on just the head unit... in the future though, will absolutely be taking a look at this.

I do have to disagree with you on one point - "no reason the DAC in the head units usb input is any better then that of a quality iDevice". Well two points actually. First there is no distinction between a "quality" iDevice and any iDevice - not sure why you used that adjective. They are iDevices, all made equal so to speak. And their DACs are all made equally and notoriously poor. So even if I'm going to go through the same # of conversions, I'd trust the 24bit Burr Browns on the Alpine decks to do the work over the iDevice chip any time, any day of the week. Especially for $150. Especially when you consider the added benefits of direct control (that is actually close enough to the original control scheme of the iDevice to be awesome) and charging of the device. But then, I'm one that hates to use actual iDevice controls in a moving vehicle, especially the new touch devices - waaay too much attention diverted from the road. Alpine's decks give back the tactile feedback and I can at this point navigate the iDevice without looking at the screen except to check which song/album/artist I'm about to pick - but not to look at the "controls" themselves? It seems the majority of others prefer to control the iDevice from the iDevice itself, but that's a personal preference so /shrug.


EDIT:
Actually this thread got me thinking and researching, and I've found out a few things.

First thing is the iDevice DAC - apparently are NOT all created equal, and the newer ones are far worse then the older ones.
Linux on iPod
"Most of them used the Wolfson WM8711/21/31 versions for playback only. Some of the units incorporated Codecs (ADC and DAC in one package) Nano 2&3, iPod 5th gen and allow full recording at 16/44.1. I have one of the Alesis consoles that has an iPod doc and I record when we play out and use the mixer to mix down two full monitors.

Even though the Wolfson dacs are capable of 24/96 the processor and storage really do not make it possible to accomplish this.

The new iPod Classic does use the Cirrus dac chips. The iTouch and iPhone still use the wolfson but I am not sure about the 3G iPhone. There has been allot of criticism over the Cirrus/Crystal dacs."

Apparently the Wolfson DACs are actually pretty nice. However, this is not the full story. Its not the "quality" iDevice DAC that really ruins things (I now agree that the "quality" is an appropriate adjective and the newer iPod classics as well as the nanos/minis are the ones that it would NOT apply to). It is what is done to the analog audio signal internally AFTER the DAC stage. From ALOAudio:
"Even if you use the very best iPod cable with your stock iPod, you are still not avoiding the serious degradation of sound quality that occurs after the internal DAC. This degradation from the cumulative effects of the following stock components that are directly in the line-out signal path and that were NOT optimized for audiophile use:

• The low quality stock SMT coupling caps after the internal Wolfson (before the stock opamp)
• Opamp output stage
• The low quality stock SMT coupling caps after the opamp output stage
• The minuscule circuit board traces that carries the analog line-out signal
• SMD resistors and inductors directly in the signal path
• The signal path inside the stock iPod dock, which contains: the dock connector plug, a very cheap ribbon cable, more minuscule pcb traces, SMD resistors, and finally the line out jack

"

Bypassing all this is certainly worth $150 to me. Sure, its not bit-stream, but then again, the price reflects that.

I DID find a few companies offering modifications to older iPods (gen 4, 5, 5.5) that still used the Wolfson DACs, and these seem like pretty awesome upgrades...


Red Wine Audio iMod basically bypasses all the internal components in the analog signal path that are not essential, and upgrades the ones that are, esentially connecting the Wolfson DAC line out directly to the plug without all the junk in between. Result is an reportedly vast improvement in the analog sound quality. Does require a proprietary cable in order to not fry your iPod/head unit which is $95, in addition to the $250 price for the mod itself. Pricey, no doubt, but possibly worth it.

ALOAudio knocks it up another notch. Not only do they partner with Red Wine Audio to do all the aforementioned mods/upgrades, they will also replace ur gen 5 or 5.5 iPod hard drive with a 128GB SSD by Super Talent. (Checked out the model they apparently use - not the best, but not terrible reviews. But then again, those were for general use in laptops and such, not for such specialized application - one in which all SSDs shine - random access of media files). Price is even more painful - $800. The SSD runs just under $300, so even with the $250 iMod upgrade and SSD, still looking at another $250 premium.

Both of the services above, while they are at it, will replace your iPod battery if you supply one. iPodJuice sells high quality replacements for $20. No reason NOT to do it!



So now I'm thinking, grab me a dead battery or crashed hard drive 80GB video iPod off craigslist for like $30, upgrade the heck out of it and I'll have a 128GB SSD, audio-phile grade portable device that is still compatible with my head unit. Actually at that point, I may as well scrap the Alpine dock and get me a nice audiophile head unit since I can then use the dock to RCA cables from iMod and use any brand that will take RCA ins for my car audio reproduction... I hear McIntosh makes amazing SQ HUs....

Posting from work, so need this disclaimer:
"The views expressed here are mine and do not reflect the official opinion of my employer or the organization through which the Internet was accessed."

 

Since the p99 allows full digital from an ipod, is it reasonable to assume that the p88 does the same thing? Has anyone ordered one from overseas? JPS

 

Going digital with my Pioneer DEH-P01 (DEX-P99RS) was HUGE to say the least.


Then again it could have been the fact the head unit is all around hugely more expensive too. All in all it is by far the most worth it upgrade I have ever done to my car.

 

I think it's awesome how that unit lets you navigate the songs from the iDevice itself while still allowing commonly used functions from the head unit.

It's almost worth paying what it cost even if you don't plan to use the advanced DSP in the unit. Like if going with an MS-8.

You get a multi source media player. A very high quality and high output variable analog section for the processor input. Master volume control from the dash or steering wheel instead of remotely from the processor if using a seperate input for the idevice digital or digtal+DAC. You don't need to worry about powering the idevice or working through any powering bugs.

 

The best part is you can STILL control what songs you want to play from the actual ipod/ipad/iphone, navigate through your phone normally while still retaining the digital connection unlike most headunits that lockout your ipod

 

I'm glad to find that out about the P99RS because thats the headunit I am looking into getting. I was researching it up but I just heard a lot of negative things about the browsing capability on it (i.e trying to find a song on an ipod and what not). I guess they didn't know they could do the searching through the ipod itself. Although it is a pricey headunit it offers a lot of features for an SQ user.

 

I like the iPod interface on the p99 more than any other single din deck I've laid hands on.

 

I don't see how anyone can possibly disagree with this.

 

Some quick points........

This is fantastic, thank you! I should have come here first. You are absolutely right, the APE is not ideal between having to select the source as you mentioned and the 1 minute boot up time I would definitely be happy to find another way. If I can figure out a good way to mount the Pure i-20 in my car I think I'm definitely going to have to go with that. Thank you very much!

 

Anytime

Also, if you want to go the apple av adapter route through hdmi out, it should work fine. ipod touch has to be one that is compatible with it of course.

post #43 and on.

http://www.diymobileaudio.com/forum/bikinpunks-product-review-forum/105710-alpine-h800-vs-h701-vs-audison-bitone-1-technical-comparison-5.html#post1323529

StarTech makes an hdmi to dvi+coax extractor that about half the price of the Kramer, but it should work the same. Can't guarantee it though. And yes, these type of boxes are the only option out there. There are cheaper ones, but I dunno about those. At some point you get what you pay for.

The beautiful thing about the av adapter is that it doesn't look to interfere with whatever the idevice and the device connected to it are doing. It just hangs there parallel with it and gives you the digital out.

That's an awesome feature so that you can still control and display the pod from say a cheap OEM head unit yet send a clean signal to the digital aux in of a processor connected after.

But for stand alone digital out, you can't beat the pure dock. I just timed the sync and boot times. I unplugged the power plug on the back of the dock, pull the iPhone off the dock, put it to play, then plugged in the power and put the phone back in right away. 5 seconds after, the music was coming through the speakers. And it only takes 3 seconds to start playing if the dock is powered up already, which would be the case in a car if it is wired to the ACC. It's also 5 seconds if the device is in the dock and power is plugged in.

As for mounting it, Dice electronics make a nice yet expensive car dock for idevices (ie G2) which can be ordered with a dock connector pass through option. That allow you to plug an dock extension cable to the back of the dock and the other end to the pure dock mounted in the dash hidden away somewhere.

For power, I'd call powerstream and see if the power supply I linked earlier would be ok or if you need something with better regulation, isolation, and protection. Don't wanna fry the thing ya know.

There's also a great music player app which would go great in the car with a pure dock. Leechtunes, has gesturing and works off the ipod app so it sounds the same. No funny audio software bugs. The best feature it has is that when the device is playing, it disables the auto lock feature. So you don't have to be bothered by the display timing out while listening to music.

 

Wow this is insane stuff. I am a total noob to this and am learning alot. I got the general idea down for ipods holding high quality digital sound files and being able to use them as a media device for certain head units. But the extent that everyone is going through is really cool. I am still in the planning stages for my set up and reading everything here definitely helps me plan and prep especially since I plant to use my ipod classic as a storage for my songs. I dont have any useful input to add to your discussion but I wanted to THANK everyone for posting up their knowledge.

 

interesting thread, quite keen to see if there any ways of connecting the apple devices myself

recently I connected up a Onkyo ND-S1 to my system and noticed quite an improvement in sound over the standard ipod connection into the headunit.

so the below
Ipad (source) > ND-S1 > optical cable to H701

my other setup (also running)
Ipod (USB) > w505 > Ainet cable to h701

my music on both apple devices are in lossless format

my problem now that is Im wanting to use my iphone or an ipod touch with a dock extender to the onkyo ND-S1.. however that doesnt seem to work (tried both 4 and 30 pin cables) obviously the 4 pin ones being for charging

 

interesting thread, quite keen to see if there any ways of connecting the apple devices myself

recently I connected up a Onkyo ND-S1 to my system and noticed quite an improvement in sound over the standard ipod connection into the headunit.

so the below
Ipad (source) > ND-S1 > optical cable to H701

my other setup (also running)
Ipod (USB) > w505 > Ainet cable to h701

my music on both apple devices are in lossless format

my problem now that is Im wanting to use my iphone or an ipod touch with a dock extender to the onkyo ND-S1.. however that doesnt seem to work (tried both 4 and 30 pin cables) obviously the 4 pin ones being for charging

Mind if I ask what cable specifically. I want to stay away from it when I try the same thing on my Pure dock.

 

Even thought i hate apple product. This was a great review for some of you guys....

Sent from my SGH-T959 using Tapatalk

 

just some generic dock extender cables from ebay
I know they work as ive used them inside, its just from the onkyo ND-S1 that it doesnt work for some odd reason, onkyo support was useless as well and didnt want to help me.

if I place the iphone in the dock, it works perfectly

 

Must be the dock is very sensitive to the change in electrical parameters a length of cable produces. Those are after all some very thin wires to fit 30 on an already thin dock connector cable. This might be one time where a "high end" cable might be useful.

 

hmm I guess I can try it as Id love to do away with my headunit and just use a Rux controller and ipod touch or iphone

the ipad is a tad too big to keep in the car.
Im just worried if I buy a more expensive cable, it may not work
and makes it harder being in little New Zealand, as the shipping would most likely be out of the return dates of the ebay sellers.

 

I don't think there is a market for audiophile dock extension cables yet, so you can probably find a high quality competent one without the ridiculous markup. I saw one the other day that looked pretty stout for under $20 IIRC. I forget the brand .

 

you could run hackintosh on a normal windows PC too
just need vmware installed and a copy of the OSX 10.6 or 10.5 etc with a custom bootloader (Darwin?)

I just got one running the other day, and it was quite neat, but soon got sick of it after a day

Im a fan of some of the apple products and agree about the above statement.
the one thing that really bugs me is how apple make it so cant do anything on it, even though the device maybe capable of doing it..

an example being that most external USB devices cannot be used due to a voltage restriction apple stick on the ipad..
the iphone being similar to an ipad.. yet the USB adapter does not work on the iphone??

I could go on..
if only Apple could allow some of these things to work then they would have a very good overall product

 

after reading this i really want to try a ida deck

 

Check some youtubes onelivinlarge, the interface is very very nice. Here is one of Pandora-link control.
And one of iPod control.

But as previously mentioned, unlike other HU's brought up here, the IDAs will NOT let you control the iPod from the iPod (or iDevice, whatever). The newer INA double-DIN does have this option, as does the P99.

Cheers!

Posting from work, so need this disclaimer:
"The views expressed here are mine and do not reflect the official opinion of my employer or the organization through which the Internet was accessed."

 

Sorry if I'm in over my head here, but what about Bluetooth? Is that not a digital signal? I have an iPad 2 that I use in my truck via Bluetooth rather than the cable for easier control. am I losing any sound quality by doing this?

 

That would be bluetooth a2dp.

I've haven't researched it much but I do know it take a file and compressed it on the fly with a type of compression algorithm similar to MP3, acc, etc. It does that in order to meet the bluetooth bandwidth limit.

The quality I imagine would depend on the each particular implementation, but I have heard that it sounds excellent on the pioneer p99rs. If you start off with an uncompressed file and send it threw a quality A2DP setup, then it should sound as good as running that file through a compression scheme and playing it from the transport or USB. IE it should sound excellent since the a2dp bit rate is as high as a high bitrate MP3 (iirc).