Inside the Onkyo ND-S1 Ipod Transport

[FAA]

Hi Guys,

Just got this today and thought you might be interested to see whats inside this little transport..

[IMGDEAD]http://gi170.photobucket.com/groups/u243/MGFLKA1BVF/IMG_0069.jpg[/IMGDEAD]

[IMGDEAD]http://gi170.photobucket.com/groups/u243/MGFLKA1BVF/IMG_0071.jpg[/IMGDEAD]

[IMGDEAD]http://gi170.photobucket.com/groups/u243/MGFLKA1BVF/IMG_0081.jpg[/IMGDEAD]

[IMGDEAD]http://gi170.photobucket.com/groups/u243/MGFLKA1BVF/IMG_0082.jpg[/IMGDEAD]

[IMGDEAD]http://gi170.photobucket.com/groups/u243/MGFLKA1BVF/IMG_0084.jpg[/IMGDEAD]

See more photos here: ND-S1 - Photobucket Groups

 

[Agi]

Very nice, all you need to do now is give us the schematics .

 

[kevinkr]

What does this thing cost? The Wadia iTransport is too expensive IMHO.. I assume it has spdif output..

 

[Agi]

What does this thing cost? The Wadia iTransport is too expensive IMHO.. I assume it has spdif output..

$180, yes it does have both spdif optical and co-ax.

 

[stephensank]

Just been doing some tweaks on a Wadia ipod deck for a client, and I can tell you that the Onkyo actually looks a LOT better inside than the Wadia, which has less than half a dozen chips, most of which have the numbers GROUND off of them, and has a crap dc-dc converter circuit(a form of switchmode power supply), which itself is fed from a crappy laptop-type SMPS 12v/1a external power unit. Although I was able to clean it up substantially, the SPDIF waveform is about the WORST I've ever seen, with several harmonics riding the signal & a nasty overshoot ringing on the leading edge of each wave. In my view, a COMPLETE PIECE OF CRAP. Further, it only provides coax spdif out, only component & s-video out(no composite), audio outs are simply direct from the ipod(no better dac of it's own on board), and there's no usb.

 

[dhaen]

Is there a further PCB? I can see that the control/dock PCB is a snap-off from the main PCB, but that still leaves a big triangle wasted.

 

[FAA]

Is there a further PCB? .

heres the whole board:

[IMGDEAD]http://gi170.photobucket.com/groups/u243/MGFLKA1BVF/IMG_0073.jpg[/IMGDEAD]

 

[FAA]

hi stephensank, do you have photo of the wadia 170i board?

 

[stephensank]

Sorry, no, I didn't take any overview photos of the Wadia board. Only a close up of the upgrade work I did on it.
Back to the Onkyo, strangely, the Onkyo has a PCM2704 and a DIT4096 on board. The PCM2704 is a USB input DAC and a USB-SPDIF converter/driver. The DIT4096 is an SPDIF driver. So, considering the lack of any analog audo outputs, it seems that the PCM2704 is strictly being used as a USB-SPDIF converter, only used to take a computer-fed USB audio data signal out to SPDIF for an external dac, through the same output that the DIT4096 is feeding from the IPOD, switched by the buttons on the top of the unit, and the dac in the PCM2704 is not used at all. Very strange. In any case, I would be willing to bet, not just because of the DIT4096, but also by the lack of any evidence of internal DC-DC conversion(at least of the SMPS type, like the Wadia has), that the Onkyo will have a hell of a lot cleaner digital output signal than the Wadia.

 

[wwenze]

Seems like the same trick used in Wadia - data sent from iPod in USB format to PCM2704.

PCM270x or 290x are often used as USB -> SPDIF/I2S interfaces to other better DAC chips because they're cheap and simple to implement.

 

[kevinkr]

The big deal with this Onkyo box is that it is much less expensive than the Wadia.. Looks like the hot tip to for spdif output from an iPod. (I know it is not the optimum solution, but it has to be a big improvement over the iPod's analog outputs which IMO sound execrable when connected to a good system.) It looks well executed and for this kind of money I can't really pass it up, I'll probably be getting one within the next couple of months.

 

[stephensank]

Sadly, the Onkyo looks five times more expensive inside than the Wadia. First time I opened up the Wadia, both it's owner & I said "So, the $400 must be just to cover the cost of paying Apple for the rights to access direct digital output on the ipod connector." It's just looks cheap as hell inside. And, since they sandblasted the numbering completely off the total of three large-ish chips in it, including the one doing the digital output spdif conversion, there's no way to know if the horrible harmonics on the spdif waveform are caused by the chip or by the DC-DC converter(which they had run the spdif output trace STRAIGHT past, within a mm or two, but replacing that trace with a shielded line only reduced the garbage a tiny bit), without disabling the DC-DC converter & directly supply the +/- rails to the rest of the unit. Adding an enormous, overkill amount of energy storage/filtering cleaned up the signal just a bit more, so I do think the translator chip is largely to blame, but budget did not allow enough experimentation to say for sure. Simply replacing the external crappy SMPS 12V power unit with a high grade linear supply had ZERO effect on the waveform quality, so problem is positively internal to the unit, at least. At least with the Onkyo, the chips are identifiable, and thus allows for thoroughly informed upgrading. I really HATE companies that grind numbers off chips. It's anti-piracy, I know, but it's also arrogantly having the company say to the buyer "Oh, we'll NEVER go out of business, and you'll ALWAYS have our service support on our crap."

 

[wwenze]

Audiophile tax... big companies that also mass-produce consumer products like Onkyo charge less of those.

 

[kevinkr]

Sadly, the Onkyo looks five times more expensive inside than the Wadia. First time I opened up the Wadia, both it's owner & I said "So, the $400 must be just to cover the cost of paying Apple for the rights to access direct digital output on the ipod connector." It's just looks cheap as hell inside. And, since they sandblasted the numbering completely off the total of three large-ish chips in it, including the one doing the digital output spdif conversion, there's no way to know if the horrible harmonics on the spdif waveform are caused by the chip or by the DC-DC converter(which they had run the spdif output trace STRAIGHT past, within a mm or two, but replacing that trace with a shielded line only reduced the garbage a tiny bit), without disabling the DC-DC converter & directly supply the +/- rails to the rest of the unit. Adding an enormous, overkill amount of energy storage/filtering cleaned up the signal just a bit more, so I do think the translator chip is largely to blame, but budget did not allow enough experimentation to say for sure. Simply replacing the external crappy SMPS 12V power unit with a high grade linear supply had ZERO effect on the waveform quality, so problem is positively internal to the unit, at least. At least with the Onkyo, the chips are identifiable, and thus allows for thoroughly informed upgrading. I really HATE companies that grind numbers off chips. It's anti-piracy, I know, but it's also arrogantly having the company say to the buyer "Oh, we'll NEVER go out of business, and you'll ALWAYS have our service support on our crap."

IMO Only sad for the fellow who bought a Wadia over the Onkyo, it's nice to see something this well made at an affordable price point, and sounds like it is better engineered as well..

Unfortunately a passion for good sound and good engineering and manufacturing practices are not mutually inclusive, at least in some parts of the high end.

 

[kevinkr]

Audiophile tax... big companies that also mass-produce consumer products like Onkyo charge less of those.

No, it goes much further than that, it speaks to core competencies and available resources.

 

[FAA]

I agree that the Onkyo looks more expensive and well engineered than the Wadia..Found some photos of the Wadia..

[IMGDEAD]https://i162.photobucket.com/albums/t277/charming01/USB170.jpg[/IMGDEAD]

Modified Wadia 170i

 

[kevinkr]

Casting a jaundiced eye on the layout that certainly is not one of the best I have seen. The lack of segmented groundplane (ground currents should not be allowed to flow randomly in the plane) is rather interesting and not particularly good practice by current standards.

The problems you observed with the design may have more to do with poor layout practices than any inherent design flaw, but without a lot more detail it is impossible to know.

 

[Horizons]

Just ordered one of these from Japan.

Based on the design, does their appear to be any advantage of the optical vs. SPDIF out?

It appears that the USB is actually an input so you can sync your ipod to iTunes while it is connected to the Onkyo. It would be cool if it included USB out but I guess you can't have it all, especially for under $200.

 

[stephensank]

Personally, I've always found even a basic quality coax rca digital cable sounds better than any optical, but optical can be good for avoiding ground loops, especially if interfacing with a computer.
Back to the Wadia, yes, the groundplane design is pretty abominable. In fact, when I replaced the spdif out line with a shielded silver cable, I first took the ground for shield & output jack from a ground point nearest the drive chip. This had the effect of making the spdif output mysteriously shut off whenever any disturbance happened on the ac mains line(like shutting off/on a power amp on same ac line), a problem which disappeared when I took the ground from the jack location, remote from the drive/proc chip.

 

[wilbur-x]

As I just bought the Onkyo ND-S1, this thread is of high interest.
Please advice if this engine has modification/tweak potensials.
(Clock/regulators/caps etc). I'm pretty newbee in this matters, so your explanations & replies are most welcome.
From this thread it would appear that the analogue section in PCM2704 is not activated.
Could this be a opportunity to make a digital pre and/or a headphone amp?