Marco
As wonderfully fun and convenient as the iPod is, there always seems to be some nagging issue that prevents it from becoming a true audiophile device.
Good luck with this, and I, too, will be excited to see if any fellow Agoners can crack the code. |
Why bother?
The music on your ipod is most likely in mp3 format. A dac can't help with what signal is not there.
You will have to consider storing music in a lossless or uncompressed format first on the ipod and then worry about an external dac. The software even warns you before saving to the ipod that the format can not be changed back once converted. That's because it is cutting out certain "stuff". However, how much can fit on a 40-60 gig ipod anyway? |
Elevick - Nothing on my iPod is in MP3 - to the mere suggestion of listening to anything compressed that way at all I'd say "why bother". I have a 60 gig ipod that holds my tunes in Apple Lossless. That's about 170 CD's which is certainly better than carrying around a box or folder with that many CD's and sorting through them every time I want to hear something in the car, or through headphones, or in a hotel, or at a friends house. It occured to me that the dock might have the potential for yielding a digital stream, but how do you tap into it other than connecting a laptop?
Marco |
Elevick-
I wouldn't assume on an audiophile forum that the music on Marco's iPod is mp3 format... And, with a ALAC lossless compression at about 200 MB per CD, you can store about 300 CDs on a 60 GB iPod. More than enough for any airplane ride I'd be interested in taking...
Marco-
Have not yet seen any digital outputs for the iPod family. Its too bad too--with a little headphone amp, a waveterminal, some nice Grados, and one of those Pod 60 6Ah batteries, you would have a nice shoebox system. |
Whups Marco, ya beat me to it.
You're only getting 170 CDs on 60GB w/ALAC? Seems odd. I thought I was running about 450MB per CD in WAV format, and thought ALAC was generally better than 2:1 compression over WAV.
Maybe I just listen to highly compressible music. Or short CDs. |
The iPod could probably be modded to bring-out a digital interface. I2S is probably available in there, but not S/PDIF, so a chip would have to be added to get S/PDIF. If it is too tight, the chip may not fit.
Steve N.
Empirical Audio
Manufacturer/modder |
Ed - I was only estimating based upon 600mb/CD in WAV (perhaps I'm off there. I'll have to see how many are actually on my iPod. Compression is about right though. My Alpine car rig is set up with a box that takes the iPod feed from its dock. I was thinking that that box was acting as a DAC since it is taking the feed from the iPod and running into an anlog input on the car deck. So naturally I thought there must be a way. Indeed, your thoughts were as mine: a kinder, more listenable iPod for traveling. My last trip I brought my MicroZotl and ran the analog inputs through the MZ then into a pair of Sony cans. The sound was MUCH better than straight off the ipod, but still left something to be desired in comparison to running the feed off my DAC when running a ALAC at home through the Waveterminal. There are much smaller headamps than the MicroZotl, several being made just for portable use, so yes, that's where my thinknig is going here.
Marco |
Hmm... I think I've heard the dock uses a line out that byplasses the audio amp in the iPod, but the iPod is still doing DAC duty. From what I gather, however, the amp in the iPod is pretty compromised, so the difference bewteen the headphone out, which uses the iPod amp, and the line out from the dock is pretty noticeable. Me, I use a highly suspect Nano with 128 kbps AAC files, just because the only time I ever listen to it is on the plane or on the metro. In either case, there is so much other ambient noise that the iPod is just kinda background music. |
Jax2,
I tought of the same, what I ended up doing is the following since as you said it the product doesn´t exist:
1. Burning all of my cds into a 1,000 GB external drive using the WAV format.
2. Using a Xitel Pro-Link from my laptop USB to send an optical cable (Kimber) to my Bel Canto DAC2 and into my system.
The optical connection sounds better that the coaxial, my feeling is that there is way too much digital noise inside the computer. Another option is to use an Apple Airport Express to send the data from your computer to your dac via the optical output (you will need to buy the Monster cable kit to get the 1/8 to toslink optical cable). Hope this will help.
Hector |
Hepl (Hector) - yep, I've done the same using a smaller (250gb) external drive (smaller drive using Apple Lossless format). I use a Waveterminal U24 and am also very happy with the setup. But I was looking for a portable solution that didn't involve toting along the laptop and hard drive. I've tried the Airport Express, but didn't like it in comparison to the Waveterminal route, which works superbly with my DAC.
Audioengr (Steve) - A direct to DAC solution would be great too (as I think you are suggesting with the I2S route), but I'd be happy if I could just get a USB feed to my Waveterminal which would do the S/PDIF conversion. The USB docking dongle won't work as it's the wrong end (and I assume wrong direction) of the USB cable. Do you think it's possible to get a digital feed via USB to go to my Waverterminal, or would that require the chip you mention?
Marco |
Wavelength Audio has USB DAC's - check out the site www.wavelengthaudio.com and see if that might work. I couldn't tell by just the quick glance, but it would be worth a look.
Hepl,
Yamaha has a 200GB hard drive recorder that writes to the drive in an uncompressed format. I got one, and when I figure out how to use it, I will put all my CD's on it.... |
Wavelength Audio has USB DAC's Yes, I know about their DACs. There are several companies with USB DAC's but they require a USB input (female). The only dongles cables available from the iPod Dock are USB male. I don't think you can reverse that or use an adapter - someone correct me if I'm wrong. Marco |
Joeylawn36111,
This is my third hard drive. I keep running out of space, I do burn the entire disks. Of course I always hear the same songs over and over, about 30% of the library. But disk space is getting cheaper and it's easier for me to burn the whole than to manually select the songs I like.
Jax2,
I just bought an Alpine CDA-9855 and KCA-420I (I-Pod interface) for my Ruf. The I-Pod can be controled from the head unit, even the information can be seen on the dash. Not sure if the unit(KCA-420I) does the D/A conversion or just allow the head unit to control the I-Pod and read its display info. You may want to try to find out more on www.ipodlounge.com.
Hector |
Hector - I have an Alpine head unit in the same series, and the same KCA-4201 iPod interface. That was the unit that made me curious if what I'm asking is possible. Alpine makes a nice head unit, but I find the iPod interface to be a bit tedious...don't you? It's still great to have access to such a great variety of music in the car, especially when driving long distance.
Marco |
As a subset of this discussion, can anyone please suggest which of the new iPods might be most suitable to audiophile applications?
Would you just get the biggest, most expensive, video iPod? Or as audiophiles, does it make more sense to skip the video, perhaps gaining longer battery life or something?
Is the possibility for digital output the same for all models? |
The only rumor I've heard that indicates any advantage was in the HeadFi forum where someone opined that the op-amp (line-out) in the more recent (video) iPods was slightly improved from the previous versions with a bit more robust output. I don't know if this is true or not. I find the output on my line out to be just barely adequate for listening on the edge of loud. If others were worse than this then I'd say definitely go for a more current version of the video ipod. Other than that, I just went for the most storage capacity, which happens to be a video iPod (60gb). I don't know if any of the current large-capacity offerings from apple are anything but "video" ipods. The only other type of ipods being offered are the smaller units with much less capacity. Unless you are using mp3's, you will be severely limiting yourself in terms of how much music will fit on one. And if you're using mp3s you may as well just glue some nails to the ends of the earbuds and call it a day. Of course if you have to have some pop star's autograph emblazened across the back of your iPod to go with your celebrity sports-star approved basketball shoes, well, then again you are limiting your selection.
Marco |
Marco,
There is third party software out now that will copy your tunes from your Ipod to your computer. Which means yes there is a digital output of the Ipod now just how you access that I don't know.
Sorry I could not be of more help.
Michael |
As an addendum to my ramblings here, I discovered that the problem I was having was with the $99 device that was providing the line output on my iPod. Can't recall the manufacturer, but I believe they were the only ones offering a dock with dual RCA line-outputs. Whatever circuitry they put between the dock and those RCA's was wreaking havoc with my output signal and the music sounded awful. I exchanged it for the much cheaper iDock and went with a $69 Signal Cable silver iPod interconnect and have been happy as a clam since. I recently noticed this mini-system by Monitor Audio claiming to be getting a digital output signal from the iPod lower connection, which it runs to its own DAC and bypassing the DAC in the iPod. If this is so, apparently it is possible...why isn't anyone making a simple cable or converter to do this? |
The Monitor Audio iPod dock, the i-deck, claims to bypass the DAC inside the ipod and take a digital bistream directly from the ipod to it's own internal dac, which sounds much better than the internal dac. I'm not sure exactly how this is implemented, it apparently gets an audio bitstream out of the dock connector because that's all it needs to have connected, but it certainly sounds better than any other ipod dock I've heard.
http://www.hometheatermag.com/ipodaccessories/106monitor/ |
Nnyc - This has me baffled...how the heck is Monitor Audio able get a bitstream from the docking port of an iPod. I thought there was no S/PDIF output within the iPod. This seems so blatantly obvious and marketable, why hasn't anyone else bothered to do this?!?! I wrote to Vinnie over at Red Wine Audio, and he pointed out that it was interesting that Monitor Audio does not list this as a feature of this unit on their own website. They do mention that it can be used with a computer via a USB connection, and I wonder if that is where the interface is coming into play. Using my computer I can pull the content from my iPod via USB or Firewire through iTunes, have the computer spit out a signal to my converter (a Waveterminal U24) and feed the digital stream from the Waveterminal to an external DAC via S/PDIF or Toslink. I wonder if AudioAdvisor and the reviewer are muddying up the description by leaving out the need for a computer in between in order to feed that digital stream to the DAC? If not, how are they getting an S/PDIF feed from an iPod? Vinnie went on to speculate that they may be using the USB port and a custom converter board (like my external Waveterminal, or an internal sound card for a computer), but added that some software would be necessary to govern that interface. Anyone have any idea how Monitor Audio is doing this? Marco |
I suppose it is possible that the i-deck reads data directly off the ipod disk as data files, treating it as just a USB hard disk, and uses it's own software to play and decode the files. The only strange thing about that is that you can control whats being played with the interface on the ipod... I haven't seen any definitive explanation yet. |
There is a program called Anapod Explorer that allows you to treat the iPod as an attached drive so you can copy files to and from as strictly digital data so there must be a way to get the digital data back out. See http://www.redchairsoftware.com/anapod/ |
I haven't read this whole thread, but I found this thing
http://www.nyko.com/nyko/products/?i=44
which I had to buy - it cost about $20. The sound is OK. I'm not sure how it's doing what it's doing. seems to answer your question though |
I haven't read this whole thread, but I found this thing
www.nyko.com/nyko/products/?i=... Nope, that's just a line output. The digital output would have to be in the form of a single S/PDIF (RCA type connection), or a Toslink connection. Anything that goes directly into an amplification source is using the Ipod as a DAC. With a digital output you would need to go firt to an external DAC. Thanks for posting, regardless. Marco |
The iPod uses a cruddy, standard Wolffson Microelectronics low-power DAC; headphone amplification is handled by the same chip. It is built into the ipod, rather than the dock, unfortunately.
You might as well use your computer or one of the newer digital media servers as a lossless source, and then rout this into a good upsampling DAC. Some of the newer upsampling CD players (eg. Cambridge Audio, Quad) will allow for digital inputs, as well. |
I think it is. I saw somewhere on the internet the pin lauyout for the ipod connector and it includes two interfaces: a USB and a Firewire. It is quite possible that when playing a bitstream is sent to usb and/or firewire...that's how monitor audio may have implemented their own DAC. |
[email protected] writes: The iPod uses a cruddy, standard Wolffson Microelectronics low-power DAC; The iPod has always used a Wolfson Microelectronics DAC. The first and second generation iPods - WM8721; third generation - WM8731L. Fourth generation - WM8975 CODEC; fifth generation - WM8758 Audio codec. Some think the WM8975 is the best sounding of these. As some know, Arcam changed from the dCS "Ring" DAC to a Wolfson DAC. Obviously there were many business reasons involved in this, but Arcam are a savvy company with a good reputation for sound quality, and Arcam chose to use chips from this Scottish DAC manufacturere. For example, the Arcam CD33 uses the WM8740 DACs, and it's a good sounding player (though I prefer the earlier "Ring" DAC). I'm not saying the WM8975 is a great DAC. I just don't think it's "cruddy". headphone amplification is handled by the same chip. It is built into the ipod, rather than the dock, unfortunately. No. The headphone amplifier is handled by an opamp output stage following the Wolfson DAC. This can be bypassed as Red Wine Audio do with their iMod. We take the analog output (line out) off of the dac chip and send it directly to the internal 1/8" headphone jack (converting it into a dedicated line-out jack) via high-end Black Gate Non-Polarized NX-Hi-Q coupling capacitors The pin outs have been published. See http://pinouts.ru/Devices/ipod_pinout.shtml. There is digital data coming out of the iPod on both the Firewire and USB outputs. But it's not in SPDIF and you can't feed it to an external DAC. The MSB modification extracts the digital data higher up in the chain and run it through custom circuitry, as shown on their web site. This is a $2000 "mod" as you cannot get the $200 iPod mod without buying the system. Regards, |
When John Atkinson of Stereophile tested the iPod's DAC he found it tested quite well. Psiberaudio offers passive/active preamp docking stations that raises the iPod signal output to a standard 2V. Psiberaudio's website may give you some ideas and useful information on getting the most out of your iPod. Their site is http://www.psiberaudio.com/iPod_2.htm. |
Ooops,
I guess I prematurely jumped into a thread that's a bit out of my league late at night or something. But now that I've actually read most of it, I'm curious about this quest for the ultimate iPod sound if it's for on-the-go listening in the car or out in the world, where a previous Audiogoner already pointed out, there's unavoidable ambient noise issues. In most cars and noisey environments, dynamic compression is a good thing. I don't know if it's possible to compress the dynamic range to spare storage space, but that would make sense in portable music player. I've enjoyed this thread and learned a few things, and I hope I didn't kill it with my previous off track response.
But it will be innovative companies like Psiberaudio that will offer solutions. |
See:
http://www.msbtech.com/products/iLink.php |
Thanks Kana813! That appears to be the real deal. From another thread, compliments of Peter_S and Monitor Audio: The digital/ audio over USB protocol has only just been released to us by Apple in September, which will mean that products in the future may use the digital data stream with local D/A conversion. I imagine once Apple begins releasing products with that protocol they would be very popular among audiophiles. As for the MSBtech device; for $2K you can buy a Mac laptop, an 500gig external drive and have money left over for lots of music. Marco |
"I imagine once Apple begins releasing products with that protocol they would be very popular among audiophiles."
Marco- I'm afraid their marketing plans will be ruled by the MP3 world and the new iPhone.
PS- I agree the MSBTech devise is way over priced, but
I'm sure some iPod groupies will still buy it.
PPS- I'd love to hear that MSB Power DAC. |
Wow. The MSBTech devise is exactly what I have been waiting for... until I saw the price.
No doubt a similar product will be around soon for much less.
You might as well buy a spare laptop, with all its advantages.
In the mean time I am using my ipod in a docking station that is connected to my pre-amp through a modified Musical Fidelity X-10D tube buffer. Surprisingly good. |
It appears that it is, at around $2K.
http://www.ipodhacks.com/article.php?sid=2085 |
I just stumbled upon what appears to be a (lower priced) iPod dock solution that has a Toslink digital audio output - Escient FP-1. Here are photos of the FP-1Does anyone know anything about this solution for potentially interfacing an iPod to a DAC? |
The Escient does not talk about modifying the iPod. This is required to bring-out a digital signal.
The only ones doing this to my knowledge are myself and MSB.
Steve N.
Empirical Audio |
Steve is correct... the Escient is most likely using an A/D converter and converting the analog line-out into optical and/or coax digital output. I've seen a few other docks like this, even via Bluetooth (e.g. Griffen Bluetrip). The MSB is the only one that does it properly.. that I know of.
Vinnie |
Hi Steve - I know about MSB but I didn't realize you were doing digital out modifications to iPods - can you point me to some additional information? |
Bwhite - The digital iPod docking station is called the iRod, for Hot-rodded iPod. It will essentially replace all of the analog circuits in the iPod with external circuits of my own design. I will bring-out the I2S interface on the docking connector. The connector will dock with my own portable box, which will have rechargable batteries, D/A, headphone amp and analog volume control (Alps). It will use the AD1853 D/A converter and be non-upsampling. I may also try to drive a low-jitter master clock back up to the iPod, locating it at the D/A chip. I am considering putting line-outs on it as well, but it may not have the space.
Steve N.
Empirical Audio |
Steve
what is the latest on our project? Have you completed a product that can bring digital out of the iPod to an external dac?
Thanks |
Johnmhuntbch - I took an iPod Video apart and mapped-out the signals. The problem in this particular unit is that the signals necessary for I2S are not present. The D/A chip is run from a 12MHz clock. It is a proprietary chip from Wolfsen, cannot find a datasheet. It also uses a half-speed bit-clock. With some effort and logic, I could generate S/PDIF from this externally, but it would be jittery.
The whole point of this was to get a low-jitter I2S out of the thing. Looks like maybe a different iPod is needed. The new ones evidently use the WM8741. This I have the data sheet for. This probably has I2S going in. Not sure which iPod to buy though. This is getting expensive. I managed to put the video iPod back together and I'm giving it to my wife for use when walking the dog...
Higher priority is getting my new Formula One DAC to market right now.
Steve N.
Empirical Audio |
Alpine makes a head unit for cars that does not have a CD player. It claims to take the digital output from an Ipod. So it must be possible.
Also, check out Red Wine Audio. They do upgrades on Ipods though not the latest ones. They upgrade the analog section because they claim the DAC is top notch already. One review I read said that the upgraded unit is pretty much reference quality. |
Alpine makes a head unit for cars that does not have a CD player. It claims to take the digital output from an Ipod. So it must be possible.
Also, check out Red Wine Audio. They do upgrades on Ipods though not the latest ones. They upgrade the analog section because they claim the DAC is top notch already. One review I read said that the upgraded unit is pretty much reference quality. I have the Alpine iPod interface in my van. I'm not certain it is the one you are referring to but it was the only one they offered when I purchased it - basically a separate black-box interface that connects to the dock of the ipod and feeds the signal to the head unit. It works great (very convenient and sounds OK as far as car stereo goes, but is easily bested by a CD in the same head unit). It does not claim to take digital out from the iPod. It is a $150 accessory (when I purchased it) and I assume it is just taking the line output like all the other inexpensive docking devices for iPod and amplifying the line signal. I am quite sure that the Alpine head unit that I use does not have an internal DAC, nor is the black-box interface contain a DAC itself according to the manual. That Alpine iPod interface has been around for a couple of years now if it is the same one I have. With all due respect to Vinnie and Red Wine, my experience with the Wolfsan DAC in my iPod simply judging from the line output and decent interconnects would certainly not suggest it is a top notch DAC. I have no doubt Vinnie can improve the line-output signal, but that would not improve upon the DACs abilities which are critical in what you hear at the other end. I found the iPod line output to sound 2-dimensional and lacking in dynamics in the systems I've listened to it...fine for casual listening, but sure wouldn't want to sit in front of it for long. I've read some positive words for Vinnie's iMod, but can't recall any giving it the specific praise you mention as "reference quality" digital front end. Is there a new review out recently or any changes to the iMod? Marco |
That is not the unit I mentioned. That is a generation or two old.
It is a new product that does not even have a CD player. It specifically states that it uses the Ipod digital outputs. I personally have their best current CD receiver which interfaces with the Ipod through a simple cable, but nowhere does it state that it is doing the digital conversion, so I suspect it does not. If the Wolfson is as good as so many people claim then the mods to the analog section that Red Wine does may achieve the results claimed. But I have not heard it, only read about it. Caveat Emptor. |
That is not the unit I mentioned. That is a generation or two old. I went to the Alpine USA site and all I could find there was the same KCA-420i adapter box that I have in my van, which definitely does not extract a digital output from the iPod. Would you provide a link that tells about the newer unit you are referring to? Thanks in advance. Marco |
http://www.alpine-usa.com/US-en/products/product.php?model=iDA-X001
Here is the url. It is the iDA-X001. Personally I am not ready give up the ability to listen to CDs in the car. Though I don't take advantage of it too often. |
Try this.... from a name you trust.
http://www.ilounge.com/index.php/news/comments/wadia-digital-to-debut-itransport-digital-ipod-dock/12256 |
Wdrazek-
Great news. Now we don't have to wait for some over priced product from Empirical Audio. |
I can't wait to get one. I wonder if Wadia is cleaning up the signal at all or passing it straight through. Either way it's a steal for $348. |
Check out this Stereophile announcement for details on how this is done. It looks like we will be seeing more of these products in the future. http://www.stereophile.com/news/010408wadia/ |
